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  #1  
Old 10-24-2015, 01:50 PM
JeepHammer Male JeepHammer is offline
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Default Solar Power For Beginners, A Tutorial...

I can't be real specific about brands, part numbers, ect. since they change all the time with new models, improvements, ect.,
And that would be getting WAY to specific anyway...

-------------------

If a little simply math scares you, then READ SLOWLY AND OFTEN,
Buy a pocket calculator, because this will all get around to basic math in the end...

-------------------

SOLAR POWER can come in many forms,

Solar THERMAL, which is using the sun to heat air, water, antifreeze solution, ect.

Solar EVAPORATION, using the heat/energy to dry food, distill water, ect.

What I'm going to focus on is SOLAR PHOTO-VOLTAIC, PV for short,
These are the panels that produce ELECTRICITY...

Now, this is a little simple, while being complicated at the same time.
A Photo Voltaic material is simply put, a material that produces electrical POTENTIAL when light strikes it.

Photons (Light) are charged particles.
When charged particles hit some materials, they knock an electron lose, and that stream of electrons are collected so you can use them as 'Electricity', Or an electrical current.

This is both simple and complicated at the same time...
And completely irrelevant if you buy commonly available PV panels.

1. Suffice to say that PV panels produce 'Electrical Potential'.
Potential is NOT MOVING, just there ready to use,

2. Electrical 'Potential' put to use is an 'Electrical Current'.
CURRENT is the actual movement of that electrical potential that was waiting for somewhere to go and something to do...

3. What you do with that electrical Potential or Current is how efficient your system will become.
There are TONS of ways to WASTE that electrical POTENTIAL,
So now we try to explain how NOT to waste that potential, make it actually produce current, and make that current DO SOMETHING YOU WANT...

-------------------------

Solar Panels will be used in ONE OF TWO WAYS.

1. You will charge BATTERIES, a storage medium.
Small 'Off Grid' solar PV will always use batteries...
SMALL means you won't be running enough panels to power up EVERYTHING when the sun is up, Small By definition...

These batteries, and the direct output from the panels will power up your appliances & electrical 'Loads'.
An electrical 'Load' is anything that uses, or wastes, your electrical potential.

With Small, Off Grid, PV systems, you will need batteries to store your electrical POTENTIAL/PRODUCTION in the day time,
So you can use that power at night...

2. The second type is 'Grid Inter-Tie' systems.
You produce PV power in the daytime, you use what you need,
The excess turns the power meter backwards banking your excess production,
The grid powers the house moving the meter forwards, using up the credits you banked in the daytime...

*IF* you have a properly sized system, your meter will show almost NO usage from the grid, you will have banked enough credit to wipe out that bill from the electric company...

There is NO battery backup, no 'Off Grid' power with a grid inter-tie system.
If the main power grid goes down, you are screwed...

The reason for this is, they don't want your solar panels electrocuting line workers. It's ENTIRELY a safety issue for those line workers trying to get the grid back up and running...

------------

Now, It should be said,
There ARE systems out there YOU CAN CUT YOURSELF OFF FROM THE GRID, and use your solar directly.
The sun goes down, and you are screwed if they don't have the grid back up,
But as long as the sun shines, you will have some power without batteries.

You should take VERY SERIOUSLY the safety issues with this system,
Use proper rated disconnects, and keep those line workers safe!

We will hold off on the tricky stuff for a while, cover the basics...

----------------------

SELECTION PROCESS...

If you want to reduce your electric bill,
DO NOT want to maintain & mess with batteries,
And batteries ARE a pain in the butt, expensive, come with an entire set of problems and safety issues you don't currently have...

Then stick with Grind Inter-Tie system that reduces your power company bill without batteries.

*IF*...
You want power 24/7, no matter what the power grid is doing (or NOT doing),
And you want to have 'Normal' home power, 120V AC/240V AC power that everything you find at the store runs on...

Then you will need PANELS to produce that power,
You will need BATTERIES to store that power,
You will need an INVERTER to convert that battery/panel power to HOUSE POWER,
And you will need a basic understanding of how all this works... EDUCATION...

-------------------------------

Lets start by saying the most miserable 'Off Grid' experience you will ever have is trying to run your home off DC (Direct Current).

Homes are traditionally powered by AC (Alternating Current),
Simply because AC was MUCH more efficient to transmit through long lines,
And AC is the world standard,
So virtually EVERYTHING is made to run off AC, not DC.

DC is what panels, batteries produce.
That DC has to be converted to AC for the home appliances,
And that takes an 'Inverter' to make happen.

Personally, I tried DC powered home, and it was MISTERABLE.
DC appliances are EXPENSIVE!
DC appliances are often cheaply made.
DC appliance take HUGE wires/cables to feed when they are high powered...
Those huge cables/wires cost a BUNCH of money, so it's economically inefficient...

If you do this,
You are MUCH better off in the long run to use an inverter, and use COMMON home appliances that are AC powered, and readily available...

If you are adding Solar to an older, pre wired home, then you don't have to change a thing if you use an INVERTER.
The home is already wired for AC, and the Inverter produces in AC...

----------------------------

Only an IDIOT wastes time/money/work/effort...

The FIRST thing you should do when considering this is to go through the home,
The 'Average' home spends about 40% of energy on LIGHTING.

The most cost efficient thing you can do for yourself is to change out those incandescent bulbs with Compact Fluorescent (CF) bulbs, or Light Emitting Diode (LED) bulbs.

The savings are staggering,
The same light from a 60 Watt Bulb,
15 to 17 Watts from CF,
3 to 5 Watts from LED.

-------

There is no such thing as BAD INSULATION!
Go around, PLUG UP THE AIR LEAKS!
Calking around windows, doors, plugging up those wall outlets that allow your expensive heat/air conditioning to escape,
Insulate the attic, rafter tails,
In the basement/crawl space, insulate the floor joist tails/floor joist spaces.

If you can afford it, put in high efficiency windows.
They come in all sizes, slip right into the casing space of your existing windows, and save a mint in energy costs.

-------------------------------

So on with the lessons...
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  #2  
Old 10-24-2015, 02:16 PM
JeepHammer Male JeepHammer is offline
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The biggest bit of advise I can give anyone that is thinking 'Off Grid' is to get a yard barn...
Or if you are out in the country and want something the termites/carpenter ants/wood rot can't eat, one of those shipping containers.

This is your 'Utilities' building.
You are no longer on the grid, you will need to produce your own 'Utilities', and they need a dedicated space.

Personally, about 16 years ago, I dropped a yard barn over my water well head (well head sticks up through the floor, protected)
And I insulated the crap out of that yard barn,
Then lined the Interior with 'exterior' sheet metal.

This serves several functions,

A. The metal makes it VERY easy to clean,

B. It traps all the stray Electro-Magnetic (EM) & Radio Frequency (RF) noise the electronics produce.
I don't have the well pump or inverter interference showing up in my TV or computer...

C. The sheet metal gives you a VERY HIGH fire rating in the event that something gives up and tries to start a fire...
Fire 'Board' under the metal, instead of plywood, will increase that fire rating even more...

D. It also protects the electronics from things like lightening.
A direct, full power strike would most probably damage things,
But the transient issues are blocked from getting directly to my electronics.

E. This also gives me a place for the water pressure tanks to rest without being in the home taking up space for the little woman's stray shoe collection!

F. It keeps the batteries out of the house, and gives them room to 'Breathe',
And for me to work around them COMFORTABLY,
Instead of being stuffed into a battery box where it's hard to work on things.
Batteries WILL need fairly frequent maintenance, so that is a big plus to have work/maintenance room.

*IF* you choose a Grid Inter-Tie system,
Then the yard barn/utility shed idea can easy be deleted.
If you are connected to the power grid, then you are probably connected to the water utility also,
This makes the entire idea obsolete.

-------------

The FRAMES of solar panels,
The panel RACKS,
And the wiring between panels are all attractive to lightening...

SO,
Lightening PROTECTION,
Even old fashioned LIGHTENING RODS, are a VERY good idea!

Most solar equipment will have a provision for lightening protection,
But it isn't a given, many systems you have to install it yourself.
USE LIGHTENING ARRESTORS!
They are cheap, easy to wire, and will save your expensive equipment!

---------------------------

The next big issue is DISTANCE...
Since Solar Panels produce in DC, that DC current has to be moved to the Inverter...

DC doesn't 'Push' as easily through wires as AC does.
If you have panels on the home roof, then it's not as much of an issue,
Since the wiring run from panels to inverter won't be very long,

But if you have REMOTE PANEL ARRAYS,
As in out in the 'Back 40', or way off in a side yard somewhere,
Then you want the inverter close to the batteries.
This is to keep the DC runs of wire short to the inverter,
Then conduct AC from inverter over the long run to the home.

------------------------

This is one of those things that people just don't think about...

While the conductor, Wire or Cable, will have the same ELECTRICAL resistance per foot,
AC reverse polarity 60 times a second.
This means the RESISTANCE isn't being hammered on directly by the electrical current...

With DC, there is a large current hammering on the Electrical Resistance full time, no let up,
So that resistance heats up, and becomes even more of an electrical resistor, which makes it heat up even more, and become even MORE of an electrical resistor, and the cycle continues...
More heat, more resistance makes more heat...
Vicious cycle...

You spend big money producing that electrical energy,
And it doesn't make sense wasting it to heat up the wiring before it gets anywhere to do anything for you.

By keeping DC runs short, and using AC for the longer runs of wiring, you reduce the electrical resistance losses.
Again, this is all about EFFICIENCY...
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  #3  
Old 10-24-2015, 02:44 PM
JeepHammer Male JeepHammer is offline
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OK, Now that we have that out of the way,
And 95% of readers are bored to tears and have fled...

This is where it gets interesting!

EVERY INVERTER WILL HAVE AN OUTPUT RATING.
Usually in 'Watts'.

For Example:
A 4,500 Watt Inverter that will 'Surge' to 7,000 Watts momentarily...
What EXACTLY does that mean?

4,500 Watts is the OUTPUT UNDER NORMAL CONDITIONS.
The unit is designed to put out 4,500 Watts, OR LESS, all day long, every day.

If something throws a big load at the inverter, Say a Heat Pump kicking on,
A fridge or air compressor kicking on,
A water pump kicking on,
The unit can 'Surge' to 7,000 Watts to accommodate that start up,
But CAN NOT sustain that 7,000 Watts for more than a few seconds.

Now, for the math that will increase the fleeing to 99%...

Watts Volts = Amps
You KNOW it's 4,500 Watts,
You KNOW the output is 120 Volts AC,

4,500 Watts 120 Volts = 37.5 Amps output from the inverter at 120 Volts AC.

If you are running something on 240 Volts AC,
4,500 Watts 240 Volts = 18.75 Amps.

Volts X Amps = Watts.
If you have a microwave that is rated at,
120 Volts, 60Hz, 950 Watts...
60 Hz (Hertz) is simply the AC polarity reversal, 60 times a second, common American power grid standard...

950 Watts 120 Volts = 7.9 Amps

Blow Dryers are energy hogs,
1,500 Watts most times, which is the limit for common household electrical outlets.
1,500 Watts 120 Volts = 12.5 Amps.

-------------------------------
COMPLETELY CHANGING THE SUBJECT...
-------------------------------

The OUTPUT IN WATTS of the inverter will determine what INPUT BATTERY CABLE SIZE YOU NEED TO USE!

The more the inverter OUTPUTS,
The larger the battery bank will need to be,
And the larger the battery STRING cable size you will need.

I'll cover that later on, but keep this simple math in mind...
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  #4  
Old 10-24-2015, 02:49 PM
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Bearfootfarm Male Bearfootfarm is offline
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Quote:
Only an IDIOT wastes time/money/work/effort...
That's very true
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  #5  
Old 10-24-2015, 03:17 PM
JeepHammer Male JeepHammer is offline
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REDUCE YOUR CONSUMPTION,
Insulate, use energy efficient lighting & appliances,
Then TRACK your energy usage.
Your meter displays the daily usage and compiles it.

Your energy provider will usually send you a statement that shows your 'Average' usage broken down by months,
And this will give you some idea how much energy you will need to produce to put a dent in the bill,
Or how much you will need to produce to live off grid.

THE LESS YOU USE, THE MORE YOU CONSERVE, THE LESS EXPENSIVE PANELS YOU WILL NEED,
AND THE SMALLER, LESS EXPENSIVE INVERTER YOU WILL NEED.

This REDUCES INITAL COST, and makes your system pay for itself faster.

---------------------

If you are living OFF GRID,
You need to determine what your current consumption will be.

There is a UL sticker on the back of every appliance that will tell you what it consumes.
These ALWAYS show the VOLTAGE (usually 120 Volts AC),
The Hertz (usually 60 in America),
And the Watts or Amperage.

With simple math, you can add these appliances up to determine what you will need MINIMUM to power up, both day and night.

Daytime you will need PANELS that equal the consumption,
Plus some extra for charging batteries,

And at night, you will need AMP HOURS of battery storage to supply your home.

A power metering unit will GREATLY increase your accuracy,
Something like a 'Kill-A-Watt' unit that tracks your consumption.
At night, if you are conservative, you won't use the power you do in the daytime while washing cloths, running the A/C full blast, or cooking meals.
You simply don't leave everything turned on for 8 hours while you are sleeping, which is what you SHOULD be doing at night when it's dark...

I'll give you some tips on conservation and usage patterns later on.

---------------

A 4,500 Watt Inverter is NOT going to run everything in the home at once.
There simply isn't enough output for that.

That's were SYNCHRONOUS INVERTERS come in.
Two, three, four inverters can link up at the same time,
All delivering the example 4,500 Watts, and allow you to run those appliances.
When the electrical load drops, the inverters 'Sleep', and draw very little current from batteries/panels.

With very little usage, by limiting the number of things you have running at one time, you can get by with a lot smaller inverter string,
But this requires PLANNING, something most life styles haven't considered.
So it's a lifestyle change that most people simply won't do...
And it's the reason for those HUGE power cables going into most homes...

The more power you consume AT ONE TIME, The larger your solar panel strings will have to be,
The larger/more of inverters you will need to support everything running at once,
And it's a waste when it comes to efficiently sizing your system...

--------------------------

For instance, A common electric cloths dryer will draw 240 Volts at 30 to 50 Amps.
240 Volts X 30 Amps = 7,200 Watts!
And that is a CONSTANT draw, not a 'Surge'!

240 Volts X 50 Amps = 12,000 Watts!
And again, this is for hours on end, CONSTANT draw!

Just the cloths dryer will demand a HUGE solar panel array,
And MASSIVE Inverter string to power it up!

Common sense should kick in here,
Either AIR DRY when possible, with a small 120 volt fan running,
Or use a GAS dryer!
In this case, a gas (LP or Natural Gas) dryer will be MUCH more efficient since gas produces heat DIRECTLY,
Instead of trying to convert sun light to DC,
Then store that DC in batteries,
Then convert that DC into AC for the dryer,
Then the dryer trying to convert electricity into heat...

Gas converts directly into heat, a small blower motor that also turns the drum, and you use a LOT less electricity...

The same is true trying to use a electric stove or furnace with solar.
When you are making 'Heat', it's ALWAYS going to be more efficient to make heat directly from Gas...

Save the electrical power for actual electrical devices that WILL NOT run on gas...

-------------------

PUMPING WATER is a big deal for 'Off Grid' or off water utility folks...
This issue is seriously lessened by a simple timer, and some pressure storage tanks.

I see people with a little storage tank, and the water pump has to run every single time they use water...
This is INEFFICIENT!

During 'Peak Sun', your solar panels are the MOST efficient.
Use a timer to run your water pump during peak hours,
Usually between 10 AM and 2 PM,
And fill LARGE pressure tanks that will last most of the night.

When the Pump does have to kick 'On' after peak sun, it only runs long enough to refill the large tanks, not kick on and off dozens of times.
Pumps take a LARGE amount of current to get running,
But consumption drops by about half once they are up to speed.

You cut out all those 'Hard Starts' by letting the pump run when it kicks on, and efficiency increases...

----------------------------

Again, make the power you need,
But use some IQ points when it comes to efficiency,
And when it comes to consumption.
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  #6  
Old 10-24-2015, 03:44 PM
JeepHammer Male JeepHammer is offline
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Now I send the last 0.01% fleeing for the door!

INVERTER SIZING, BATTERY CABLE SIZING, BATTERY STRINGS & BANK SIZING...

OK, we will stick with that Example 4,500 Watt OUTPUT inverter,
How do you get solar panel/battery bank power to it PROPERLY...?

Here we go!
4,500 Watt Inverter Output...
4,500 Watt Inverter, add 25% for inverter losses, resistance in lines/cables, and for a safety margin...

4,500 Watts + 25% Losses/Safety = 5,625 Watts TO the inverter from the batteries (at night).

Now, what is the INPUT VOLTAGE of your inverter?
Our 'Example' will be 24 Volts battery power.

STAY WITH ME HERE, THIS ISN'T AS HARD AS IT SOUNDS!

5,625 Watts INPUT 24 Battery String Volts = (rounded) 235 Amps DC.

The inverter at FULL OUTPUT, will need cables big enough to deliver 235 Amps without heating up...

---------------------------------------

To determine EXACTLY how large of cable you need to conduct 235 Amps DC from batteries to inverter,
You need a DC conductor size chart...

The 'Internet' conductor size charts are all for AC,
Or they are for INTERMITTANT DC (usually automotive) use.

The Industry Standard for DC is, and pretty much always has been the Brown & Sharp Scale.

Here is the Brown & Sharp Scale,
Pretty much everything you need to know when working with high amperage DC power in one place, and that's why it's been the industrial standard since 1903...



Look in the AMPS column, find a cable that will transmit the amperage load you are looking to use,
And look left for the cable size you should use.

------------------------

We are looking for a cable conductor LARGE enough for 235 Amps continuous,
This shows up as
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Old 10-24-2015, 04:04 PM
JeepHammer Male JeepHammer is offline
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Hit the 'Enter' button by mistake... Can't seem to get the Brown & Sharp scale to display, probably because I'm new,
And I can't get the 'Edit' button to show me the post,
So here we go again...

235 Amps CONTINOUS will take a 000 Gauge (3/0 Ga.) cable size for the main lines to the inverter when the inverter is running at full capacity.

These are JUST the mains, battery string cables can often be smaller, I'll get into that in a minute...

So here you go again, just to clear things up,
4,500 Watt OUTPUT inverter,
24 Volts INPUT to the inverter,
25% Increase in cable size for safety & line/inverter losses,

4,500 Watts + 25% safety & losses = 5,625 Watts.

5,625 Watts 24 Volts INPUT Voltage = 235 Amps.

Cable Size for 235 Amps is 000 Gauge (3/0 Ga.) for the main feed to the inverter.

-----------------------

Mains will connect to ALL battery STRINGS.
(Strings make up the battery bank as a whole)

If you have 2 battery strings, then the BATTERY STRING wiring is cut in half,
235 Amps 2 Battery Strings = 118 Amps (rounded).

118 Amps need a 3 Ga. cable between batteries and to the mains.

This is a SIGNIFICANT REDUCTION in the cable size, and the cost.

With this line of thinking, some will think if you have 4 battery strings, you can reduce cable size by a factor of 4...
DO NOT DO THIS!
You can quite easily get cables too small to support the inverter,
And that is VERY HARD on the cables AND inverter.

Half inverter demand is about all you want to reduce in a simple system,
Something without a BUNCH of protection to prevent 'Brown Outs',
And keeping demand from heating up the connected cables *IF* a battery string connection fails dumping the full load on one string of batteries.
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Old 10-24-2015, 04:15 PM
JeepHammer Male JeepHammer is offline
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NOW!
Same 'Example' 4,500 Watt Inverter, But powered by 48 Volts battery strings...

When voltage INCREASES, Amperage demand decreases.

Remember, you are working with TOTAL WATTS,
When the input voltage goes up, the amperage demands will go down...

4,500 Watts OUTPUT,
48 Volts INPUT,
25% Safety Margin.

4,500 Watts + 25% Safety Margin = 5,625 WATTS INPUT.

5,625 Watts 48 Volt Strings = 117 Amp Main Lines from battery strings to inverters.

Brown & Sharp sizing shows 2 Gauge Cables for mains.

Two battery strings would reduce by half,
117 Amps 2 Strings = 59 Amps (rounded),
That's 6 Gauge cable between batteries and to the mains.

------------------------------------

Since 24 & 48 Volt input are the most common inverters out there, I HOPE this helps explain the cable sizing mystery to the inverters and between batteries...
Something that is CONSTANTLY screwed up when I'm hired to diagnose issues in DC wiring.
You get it for free.
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Old 10-24-2015, 04:38 PM
JeepHammer Male JeepHammer is offline
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Cable Size, and Terminal CAPACITY, are the two most common problems with battery/inverter connections, bar none.

Too small of a cable WILL NOT transmit the power the inverter needs,

Even if the cable is the correct size for the system,
There are often cheap, low capacity TERMIANL ENDS limiting the current flow from batteries to inverter.

Those same low capacity terminals also limit the production from the panels to the batteries and inverter.

Making heat out of electricity is ALWAYS inefficient, and a waste of your expensive panels & batteries.

----------------------

This is where I'm going to take a TON of crap from the AC wiring guys, that don't have to deal with CONSTANT, DIRECT CURRENT...

When you make a terminal connection on the end of a cable,
There is ONLY ONE 'PROPER' Way to do it...

That's a HARD MECHANICAL CRIMP,
This is a MECHANICAL CONNECTION, not a proper electrical connection.
This simply keeps the wire in the terminal, a mechanical process.

ELECTRICAL SOLDER IS THE ONLY COMMON ELECTRICAL CONNECTION. PERIOD.
If you don't solder your terminals, you are creating a problem that will come back to haunt you, especially around batteries...

Solder gives you as close to a 100% electrical load transfer from cable conductor, to terminal conductor.

Soldered Connections also seal out most of the corrosives that will attack your copper conductors/cables.
Anyone that has worked with batteries, or handled copper exposed to the elements knows that virgin copper (No Alloys) is VERY reactive with oxygen, and oxygen bearing moisture.

Add in a little battery acid/acid vapor, and that copper goes 'Green' in a few days to a few weeks.
ANY CORROSION AT ALL reduces efficiency since when you see corrosion, that is virgin copper conductor you NO LONGER HAVE, and that's lost current carrying capacity...
When you see 'Green' or 'Blue', that is OXIDE, and copper oxide is NOT a proper conductor,
And it's money out of your pocket you spend on those fine, high quality conductors!

MECHAINICAL CRIMPS ALONE leave air spaces between wire strands in your cables,
Those air spaces ARE GOING TO CORRODE, since oxygen will corrode copper directly, without anything else in the mix...

Add in some moisture or acid, and that corrosion process accelerates like you would NOT believe!

Electrical Solder simply seals up the air spaces,
Gives all those little exposed strands a conductive surface to transmit power, and makes your terminal connections more efficient, while saving them from eventual, and certain death...

-------------

If you are a SMART bunny,
You will use a 'Silver Bearing Electrical Solder'.
Electrical Solder with somewhere between 2% & 4% silver content.

Silver is a PREIMUM electrical conductor, but way too expensive to make all the conductors out of.
The silver 'Floats' to the surface, providing an environmental seal,
And it will bond to the copper surface, providing a superior electrical connection.

I'm NOT talking 'Silver Solder' here that takes a oxy torch to reach melt point,
I'm talking a common silver bearing electrical solder you can melt with a soldering iron or torch on larger cables/connections.
It's common, easily found, and far superior to the 'Discount' solder you find.

While we are talking solder here,
NEVER, EVER, UNDER ANY CIRCUMSTANDS, use ACID CORE PLUMBING SOLDER on electrical connections.
You might as well be dipping them directly in the batteries!

DO NOT use the 'Liquid' copper pipe cleaner on your connections!
Again, you are introducing acid into your connection, something you will regret.

ROSIN CORE ELECTRICAL SOLDER ONLY!

-----------------
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  #10  
Old 10-24-2015, 05:14 PM
JeepHammer Male JeepHammer is offline
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In Industrial, High Amperage Situations,
I spend half my life cutting off terminal ends,
Replacing them with something that actually works for the application.

Terminals are NOT created equal!

Anyone that has ever worked with 'Crimp On' terminals knows this.
They are made to crimp onto a LARGE high capacity wire or cable,
They have a LARGE hole for a big, high capacity connection,
And there is a little bity neck between the two!
Totally incapable of conducting the current the cable and connection are capable of...

The 'Ring' or 'Eye' are often very thin, again, just not enough material to conduct the current,
And the contact ring is very NARROW, so again, the terminal end can't conduct the current load, simply lack of contact with the threaded stud.

These are EASY to find, believe it or not,
The little hand held Temperature guns, usually have a laser to direct them,
Will tell you if you are getting a good, solid connection or not.

You simply shoot the wall, see what ambient temperature is in the room,
Then shoot the connection...
If the temperature increases, the terminal is a resistance point in the circuit.

When cables/terminals are PROPERLY SIZED, you normally won't have a temperature increase...
Circuit Resistance will show up as heat, and that little temp gun will show you where the resistance is...
Cables that heat up are too small, terminals that heat up are too small...

------------

The next thing I spend my life fighting is 'Flattened Tubing Lug' terminals.

When they squish copper tubing flat, there is still a void between the two sides of the tubing.
Since the tubing has already started to corrode ever so slightly, the two halves will NEVER bond, no matter how much pressure they use.

This creates a 'Highway' for corrosion INTERNALLY in the terminal you CAN NOT see without cutting the terminal end apart.

If you use 'Flattened Tubing' lugs for terminal ends on cables,
Make darn sure you solder the inside flattened part SHUT before you use the lug on anything!



On the left, you can see the gap I'm talking about, next to a terminal that DOES NOT have the gap.

This also shows you the VERY SMALL contact patch on the flattened tubing lugs, around the stud hole,

Compared to the 'Blind Socket' on the high amperage terminal ends,
No place for corrosion to creep into the cable... Larger Contact Patch for current transfer, HEAVY copper sides to conduct the current from cable to Contact Surface...

-----------

When that corrosion creeps up the gap in the terminal, it will reach the cable and corrode it.

That is what happened to this cable.
After just a few months, it wouldn't conduct 1/4 of it's rated capacity,
And since the corrosion was HIDDEN, no one had a clue WHY the particular machine wouldn't work...



An infra-red temperature gun found this problem in about a minute,
The terminal/cable was so hot it practically maxed out the display on the temp gun...

Put a BLIND, HIGH AMPERAGE TERMINAL END on this cable, and it's been working for the last 10 years or so with no temp increase,
And YES, I do ROUTINELY check my connections with the temp gun during maintenance.
It's the easy way to detect 'Issues' before they become full on Problems.

---------------
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  #11  
Old 10-24-2015, 05:17 PM
JeepHammer Male JeepHammer is offline
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Once you get a HARD CRIMP,
THEN ELECTRICAL SOLDER,
You would spend a little more time and ENVIORNMENTALLY SEAL the terminal ends.

HARD CRIMP, GOOD TERMINAL ENDS...



SILVER BEARING ELECTRICAL SOLDER THOSE TERMINAL ENDS,



THEN ENVRORMENTALLY SEAL THOSE CONNECTIONS!
HEAT SHRINK TUBING WITH GLUE TO SEAL THEM UP...

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  #12  
Old 10-24-2015, 05:35 PM
JeepHammer Male JeepHammer is offline
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The NEXT thing that is NEVER covered, CABLES...

If nothing else, Efficiency should be the name of the game when you consider wire/cable.

USE NOTHING BUT VIRGIN COPPER!
Alloys increase resistance, so you have to use a LARGER, more costly cable to conduct the same amount of current.

Use FINE STRAND cables.
Fine strands pack tighter, so there is simply more copper in fine strand cables,
Depending on application, conduct more current.

'Battery Cable' or 'Battery Wire', Generic at best, is thicker strands, which leaves more air space between strands, that means less copper.
More air space means POTENTIAL for a highway for corrosion.

'Battery Cable' also has VINYL insulation.
Vinyl will readily melt, when it catches fire it's VERY hard to put out,
And it cracks when exposed to UV light or caustics/corrosives.

I recommend 'Welding Cable' for most high amperage applications.
It's fine strand, it's virgin copper most times,
It's ENGINEERED from the start to handle high amperage.

It's insulation is 'Rubberized', abrasion resistant, temperature resistant, chemical & corrosive resistant.
In every way superior to generic 'Battery Cable' you normally find...

And it's AVAILABLE, every welding shop has great spools,
Most well stocked parts stores (like NAPA) will carry it,
It's reasonably priced since it's produced in great quantity,
And the finer strands make it MUCH easier to work with, bends easily, shapes easily, isn't rigid enough to cause vibration issues,
Comes in every common cable size from about 6 Gauge to 0000 Gauge (4/0 Ga.)...

Welding Shops will have actual HIGH AMPERAGE terminal ends,
Since welders MUST have good terminals to conduct the current to the weld.
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  #13  
Old 10-24-2015, 10:35 PM
JeepHammer Male JeepHammer is offline
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No Matter How Small The System,
Anything Grid Inter-Tied will need to have NEMA (National Electrical Code) rated equipment.
Your inspector simply will NOT pass it for use if every single component isn't NEMA approved.

If you are going Off Grid,
For a back up or for getting off the grid entirely, there are some things you can do that will save money without jeopardizing your safety.

One of those things on smaller Off Grid is DC power disconnects.
You MUST be able to disconnect battery strings from the inverter, cutting the power to the inverter.

Same with cutting power to the inverter from the panels.

On larger systems, by all means, stick with the usual 'Snap' switch,
You yank a handle on the side of a box, the circuit is disconnected.

On smaller systems, you can get by with quick connect plugs...

My battery strings are on 'Anderson' type quick Connectors with 'Yank' handles.
So are the solar panel strings.

Anderson Connectors,



Anderson Connectors are virtually fool proof, very cost effective, and rated for High DC Amperage, Commonly used in industrial equipment like electric fork lifts.

I would caution you to use name brand 'Anderson' connectors and not the 'Knock-Offs', the difference in quality is worth the few extra bucks you will pay for actual Anderson made units.

These come in a bunch of different sizes, and colors.
This allows you to size the connector to the application,
And the color for the application.



There are rubber 'Boot' covers for the disconnected ends, which keeps the crud out of the connector, and keeps the connector terminals from getting into anything they shouldn't,

There are handles for quick release,

There are boots to seal out corrosives,
They make for a quick, clean and very efficient battery string/bank wiring that is nearly fool proof.



You will notice there is a lot going on in this picture,

Upper Row, Left, There is a rubber Anderson boot to protect the connector end when not in use,
2nd Left, Half an Anderson connector, with terminals showing, not installed,

3rd Left, the smallest/cheapest Lug Terminal end I will use around batteries. Notice it's NOT bare copper...

TOP, 1st & 2nd Left,
Two seriously heavy duty Lug terminal ends.

3rd Left, a sold copper batter post terminal, not soft lead terminals like you see most places,

TOP MIDDLE, This is a SOLID COPPER Junction Terminal.
Use this instead of stacking two end terminals, creating a place for corrosion to take over or a cable to come loose.

Depending on application, this is called a 'Tap Tube',
A tube connector for the cable, with an accessible 'Tap' to input or draw power.

I am particularly fond of these on my mains, and smaller sized, on studded battery terminals since I don't have to stack cables/terminals.
Being heavy duty SOLID COPPER, they don't have the issues smaller terminals do...

-----------------------------------

The one place you NEVER want to go 'Cheap' is Circuit Breakers & Fuses.
DC rated breakers are expensive, but worth every penny...
And be aware, a 'Breaker' is NOT a manual disconnect!
Don't think an inspector will let you get away with using a breaker for a disconnect...
If they are trained, they will catch it in a heartbeat and fail you system.

When you are working with small, off grid, you CAN use replaceable DC fuses.
They cook, so they have to be replaced when they blow, but they are MUCH cheaper than DC breakers, and they are available about everywhere.
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  #14  
Old 10-25-2015, 11:42 AM
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12vman Male 12vman is offline
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Quote..
"Lets start by saying the most miserable 'Off Grid' experience you will ever have is trying to run your home off DC (Direct Current)."

Now, Wait a minute.. And, Welcome to the Mix..

That could be true for the most but not for me. I've adapted rather well in the last 25 yrs.

I have a simple 12 V.D.C. system with far less equipment to worry about. (Panels, Charge Controller, and Batteries) I'll admit, my electronics background is sure a blessing and I can figure out most issues that the normal Joe couldn't imagine..

It all depends on what one wants with what one has to work with. Most folks can't afford thousands of dollars to set up a system to operate things "Normally" so buying appliances from the big box stores is easy..

Maybe this thought should be another thread..
__________________
"Without Deviation from the Norm, Progress is not Possible".
*Frank Zappa*
"Two roads diverged in a wood, and I I took the one less traveled by, And that has made all the difference"
*Robert Frost*
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  #15  
Old 10-25-2015, 01:08 PM
JeepHammer Male JeepHammer is offline
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"Miserable" as in needed an inverter with HUGE cables to get a Pop-Tart heated in the microwave...

Miserable as in waiting an HOUR for a 12 volt 'Cooker' to warm up a can of soup...

Most people are going to buy those little coffee makers, cookers, ect. from truck stops, and they are poorly made and take WAY too long to heat anything...

Since it's pure HIGH AMPERAGE doing the work, they are VERY hard on batteries, and most people running a 12 volt system use the wrong batteries anyway, and very small battery strings.

My 'Camp' quickly started to consume Propane...
Lights, cooking, heating...
Propane isn't 'Renewable', and although I still use a little propane,
I keep it to a bare minimum and use solar for most things,
And I use that solar at 120-240 VAC.

I tried it while I was improving the land I purchased, and I'll never do it again...
17 miles from 'Town', so I stayed on the land on weekends, vacations until I got around to building something that worked.

----------------

Just a LOT more simple to set the panels, set the batteries, set the inverter,
Then run 120 VAC to my camp/shelter, and later on, larger inverters to the house.
I admit it, I'm addicted to 120 VAC appliances you can get something done with in short order, and don't cost a fortune!

------------------

I 'Backed Into' Solar.
I believed the far right wing paid pundits (paid by big energy), that solar was a 'Gimmick' and didn't actually work...

SO!
I started with battery powered tools...
Batteries always dead, or died shortly after I started working...
When you are living in a tent, you start work at sun up, and work till sun down.
Battery powered tools work somewhere between 2 minutes under heavy load, and will work about 2 hours under light load.

So I bought gas powered (2 cycle mostly) tools.
I can't keep a 'China' 2 cycle engine running.
Turns out, they use fuel line that dissolves in gasoline, and some of the carbs were plastic that dissolve in gasoline.
Turns out it wasn't me after all,
And they are HORRIBLY expensive!

So I got a generator.
Nothing like listening to a Briggs scream all day, drilling into your brain!
Extension cords everywhere, back to corded tools that WOULD work all day.

So, when LITTLE jobs came around, or jobs in remote locations,
You LOAD UP the generator, the tools, the extension cords,
Haul all that out there for a 10 minute job,
Then load it all back up and haul it back...

SO,
For those little jobs, I stripped out the guts of the battery on the battery powered tools,
Hooked up a cord,
And ran them off the Jeep battery...
Still had cords, but pulling a battery out of the jeep on quick connects was MUCH easier than loading up the generator...

Several batteries in equipment around the homestead,
So I stumbled onto the battery maintainers, solar cells, that kept stuff charged up when not in use.

I started using them to charge batteries while I was working through the week, worked OK, not much issues...

Then laid hands on a couple of full size (Used) solar cells,
And I was off to the races!
Worked OK for charging, but MISERABLE to try and live off of.

Now I have a golf cart, solar panels on the roof,
Inverter in the back sucking the cart batteries,
120 volt tools, extension cord on a reel,
Also have a battery powered air compressor mounted, so I have air tools on my job cart.

When the job cart isn't working for it's living,
It's an extra battery string plugged into the 'Utilities' shed powering the house...

I drive my extra batteries around, they do work, instead of sitting on the floor doing nothing...

I can buy those corded 120 VAC tools, which are cheap and powerful, and they work all day since the cart has enough battery reserve to work all day...

Like I said, it's been an evolution, I've tried the 'Dedicated' stuff, don't much care for it,
I have it worked out now where it's little to no bother, nothing goes to waste...
NOTHING GOES TO WASTE...
And I don't have to do three jobs to get one little 'Honey Do' done.
Everything is in the cart, I pull the heavy connector, and I'm off to the job site, no screaming generator, no loading & unloading the generator, no fiddling with air hoses or extension cords, no pulling a car battery around to power a 'Cordless' tool...

NO MORE BUYING those expensive as crap cordless tool batteries,
NO MORE BUYING & FIXING those expensive as crap 2 cycle gas tools,
The golf cart has enough batteries, with creative wiring & quick connects, I can weld steel from the cart batteries.
Takes me about 2 minutes to set up and be welding...
No gas powered welder, no loading or unloading a gas powered welder...

It's hard to argue with hose/extension cord reels, tool storage, welding,
And a SILENT, self propelled power station!

I know, two old panels aren't enough to run much,
But if I run the cart down completely, and it won't get back to the shop,
I simply leave it a day in the sun, and it will charge enough to get it back,
Plug it into the big solar array, and charge it up again...
So far, I've always made it back to the shop at the end of the day, but it wasn't very spunky...

Having that extra battery string out there, just waiting to power up the house in the event the main battery string fails, is worth it's weight in gold when you are off grid...

In my case, it's a back up to the back up to the back up...
I have a big welder/generator in the shop that can run EVERYTHING when it's fired up,
I have a 17,000 Watt Onan generator that is the 'Normal' back up,
And the golf cart is a SEAMLESS battery reserve that does mechanical work when it's not hooked to the house.

I'm covered, and since the golf cart was free (when I purchased the batteries in it) it's a more than welcome addition to the homestead...
Instant transportation, large battery reserve, all kinds of work around the homestead, never have to worry if it's going to 'Start' after sitting around...
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  #16  
Old 10-25-2015, 02:16 PM
JeepHammer Male JeepHammer is offline
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Terminal Ends for high CONTINOUS Amperage, Particularly in battery strings/banks...

Some people don't recommend this,
But I've found it VERY handy in my battery string connections...
I will SOLDER the terminals ends together.

The reasoning is the same, 100% contact in terminal surfaces gives you the best possible conductivity,
AND,
Solder seals out corrosion.

I use CONNECTORS, Like the Anderson connectors explained/shown above when my connections will have to be frequently broken,
But there are connections that will RARELY broken other than checking for corrosion,
And if those connections are soldered solidly, there is no need to check for corrosion...

Soldered Stacks of terminals are also a warning,
If you see the solder 'Creeping' where the stack has DE-Soldered, then you know there is a problem, too much heat is a huge red flag, time to investigate and figure out whats going on.

An old trick,
Take a piece of rosin core solder, use heat to seal both ends,
Stick that in the connection joint where it sticks out.
If it melts off, the connection is getting WAY too hot!
It's visual reference, rather than using a thermometer.

-------------------------

NOT everyone will need to do this,
I have a bad back, and don't like bending over, working on the floor, doing maintenance on cables/batteries.

My batteries are on 'Carts' up off the floor,
I run a 2"x6" board above my battery strings.
This 2"x6" board is a place to mount the charge controllers,
The main lines to the inverter, give support to quick disconnects, ect.

Puts everything right at face level when I'm working or doing maintenance.

A small battery bank will more than likely have all the same age, size, type of batteries,
And you can let the battery charger built into most modern SOLAR rated inverters charge your battery bank.

If you have a very big system, or you expand your system,
You will have different age, size, type of batteries in each string making up the battery bank.

This is where you need charge controllers for each string of batteries that are different age, size, type.
A charge controller will charge the SIMILIAR batteries in your strings,
The strings can be different since they are getting exactly the charge they need from independent charge controllers.

I'll go over more of this in batteries later on,
But different AGE, SIZE, TYPE of batteries CAN NOT be mixed in the same strings,
But a string of all older, or different type of batteries, and the next string can be brand new batteries, those will get along with separate charge controllers...
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  #17  
Old 10-25-2015, 03:23 PM
JeepHammer Male JeepHammer is offline
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BATTERIES...

1. NEVER, UNDER ANY CIRCUMSTANCES, PUT ANYTHING INTO A BATTERY BUT DISTILLED WATER!
The FASTEST way to kill battery longevity is to use 'Tap Water', 'Softened Water', 'Drinking Water'...

All of the above carry dissolved solids, salts, chemicals that will kill your battery, either quickly, in the case of chlorine, or over time in the case of 'Hard' water from the tap.

2. NEVER, UNDER ANY CIRCUMSTANDS, USE DIFFERENT AGE, TYPE, SIZE BATTEREIS IN A 'SERIES' STRING.
You CAN have all the same age batteries in ONE string, then use new batteries in a different string...

You will need a charger/charge controller for each string that is different age, size, type that are grouped together,
But you can have strings in your battery bank that are dissimilar.

Older, Smaller, Weaker or Different Type batteries will demand charge at different rates,
The 'Weaker' will demand charge full time, while the 'Stronger' batteries get cooked by the overcharge.

When you replace, or expand your battery bank, replace full strings, use a charge controller for each string so the 'Weaker' strings don't demand charge and cook your newer/stronger batteries.
It's that simple.

3. HAVE A MANUAL DISCONNECT FOR EACH STRING IN THE BATTERY BANK.
This allows you to take ONE string off line for maintenance, replacement, testing, whatever you need to do.

I use 'Anderson' connectors on each string, this allows a quick and positive disconnect that CAN NOT accidently get reconnected.

You CAN buy a DC disconnect box with a side handle, but that is VERY expensive, especially when you run several small strings of different age/size/type as you expanded...

4. EXPECT WORK & LEARNING SOMETHING NEW!
Batteries don't take care of themselves, And since high amperage DC isn't what people normally learn,
(If they learned anything about electrical work at all),
There WILL be a learning curve!

The LONJEVITY of your system will depend on exactly how much time you invest...
Proper terminals, Cables, Connections, Corrosion Prevention, Care & Feeding of the batteries will all combine to give you a LONG, HAPPY service life.

Poor cables will limit the output ability of the inverter,
Poor wire connections from panels to batteries will limit the efficiency of the panels,
Poor battery connections will cause you no end of corrosion problems,
Poor maintenance habits will cost you big time with early replacement of the batteries...

This is like anything else in life you have to work for,
The more you put into it, the more you get out of it!

Keeping battery terminal connections CLEAN & SEALED will prevent corrosion, reduce resistance losses in the system,
Properly sized, and made, cables/wires/terminals will reduce losses in the system, and greatly improve service life.
Every bit of resistance you beat out of the system is dollars in your pocket since it's 'Watts' to the home instead of wasted in the lines...

Keeping that battery PROPERLY FILLED with electrolyte will make that battery live much longer,
The longer that battery lives a useful life, the lower your overall cost.
Something as simple as 'Watering' can screw you out of years of service, require expensive replacements,
Even cause issues with the rest of the system.

5. SAFETY FIRST! BATTERIES CAN EXPLODE!
I hang my safety glasses, and my face shield on a hook in the middle of the doorway...
This makes SURE I don't 'Forget' to put both safety glasses and face shield on before messing with batteries!

My disconnects are mounted in such a way I can't easily get to the battery strings WITHOUT disconnecting that string. They simply stick out in the way with a big red handle on them...

All my battery bank tools are dipped in vinyl insulation material.
I don't want to move a wrench too far and short out, I don't want a dropped pair of pliers lighting up a 4,000 Amp DC circuit...
A can of that vinyl dip is about $4 and goes a LONG way.

Heat shrink tubing makes good insulation also...

The battery room vent fans, full size fans, kick on when the door is opened.
This took all of a $2 switch to accomplish.

Battery box or room MUST HAVE PASSIVE VENTLATION!
Fans are OK, but they fail,
Passive ventilation never fails and is cheap/easy to do.

If you can't afford a smoke/fire alarm for your battery box/inverter shelter,
Then you can't afford electricity at all...
It's VERY EASY to move the 'Beeper' on those cheap smoke/fire detectors if you need to...

COVER YOUR TERMINALS!
This takes nothing more than rubber bath mats,
The plastic tops off spray cans,
Old inner tube sections,
Even Tupperware,
Just something to keep 'Stray' conductors form reaching live terminals...

The stuff you need to watch for,
Metal shop broom handles, Levels, Framing Squares, ect.

YUP! I melted an aluminum level down pretty good while installing shelving when it fell onto the battery mains...

BATTERY TOOLS!
You WILL need SPECIFIC battery tools...

1. A LOAD battery tester.
One with 'Jumper Cable' looking clamps and heavy wires, that fully LOADS the battery.
This will tell you if you have a battery laying down on the job.

2. SPECIFIC GRAVITY HYDROMETER WITH TEMPRATURE CORRECTION.
Look like a turkey baster with a thermometer inside a glass tube.
This will tell you ELECTROLYTE state.

3. One of those little hand held infra-red thermal guns.
About $20 and you use it on batteries, a battery warmer than the ones around it is laying down on the job, sucking up current and producing too much heat.

Use it on the terminals, a higher than expected terminal connection is one that is laying down on the job.

Use it on cables, a warm cable is either too small, or it's corroded inside where you can't see it.
Occasionally, you will run into a cable with a defect inside the insulation, this will detect it by the heat it produces.

If you use heat sinks, like on your inverter, or diodes to isolate battery strings, this will tell you very quickly if you are running over the limits of that diode, if it has loose connections, ect.
Particularly handy for Micro-Hydro or Wind where you produce in AC and rectify to DC, This will let you know if you need a bigger rectifier in about 2 seconds...

ANYTHING that is heating up is resistance, and resistance is turning dollars into heat...

4. Assorted cleaning equipment, terminal cleaners/scrapers, brushes,
That spray on battery terminal protectant, ect.
Try and stick with Stainless Steel brushes,
And use Emery Cloth instead of generic sandpaper.

5. YOU WILL NEED TERMINAL CRIMPERS, TORCH FOR SOLDERING, ELECTRICAL SOLDER, HEAT SHRINK TUBING, & A HEAT GUN.
If you buy Terminal Crimpers, get the big, long handle type with tight fitting dies...

You can get around this EXPENSIVE tool, but it's a pain...
Most times, where you buy your terminals/cables, they will crimp your terminals on the cables for you...
But that means cutting the cable to size, taking the cable/terminal BACK to the shop where you purchased, and having them do it.

If you have a very large battery bank,
Then $300 for a good terminal crimper will pay for itself in time/gas/aggravation alone.

USE A HEAT GUN ON HEAT SHRINK TUBING!
If you use an open flame, no matter how careful, the heat shrink WILL be damaged.
Heat Guns are $20, remove paint/varnish, ect. so it's not a single use tool,
And if you take your time, shrink the tubing properly, it will last a LONG time...

Properly made and sealed up cables will last a LONG time,
But you probably want to add about 4" of cable to your battery terminal sections...
Sooner or later, those battery terminal ends WILL corrode, and the extra 4" of cable allow you to cut them off your expensive cable,
And give you room to replace.

This will give you a very neat, custom made wiring harness that will last for decades with very little maintenance or repair...
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  #18  
Old 10-25-2015, 08:23 PM
JeepHammer Male JeepHammer is offline
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BATTERIES, CARE & FEEDING,

1. BATTERIES HATE HEAT!
You see insulated battery boxes with batteries stuffed in as close as they can get them...
This is fine if you live someplace that is sub-zero most of the year,

But if you live where it gets over 50F., then it's a REAL good idea to space your batteries apart, and up off the floor so air can get under and around them to evacuate heat.

Batteries 'Like' temperature between about 45F. and 70F.
Batteries are the most efficient around 55F.

Batteries generate heat, both when charging and discharging.
When it's very hot, they have a very hard time dissipating that heat and can damage themselves.

After about 15 years of doing this off grid, I've come up with a system that works fairly well in both freezing, and 100F.
This is pretty simple...

My batteries are on wheeled carts, so I can pull the battery strings out to do maintenance,
Those carts keep the batteries about a foot off the ground.
The batteries are in an angle iron tray, so the bottoms of the batteries are open to the air,

In the summer, they are spaced about 4 to 5 inches apart, so hot air can rise, draw in cooler air from below, and cool themselves.

In the winter, I simply push the batteries together, strap some foam board insulation to the sides, bottom, top and let them keep themselves from freezing, no matter how cold it gets outside.

-------

I've also built battery boxes for other people, simply putting latches in the corners allowing insulation to move back away from batteries and let air in,
And built in slip in insulation, when pulled out allows air flow under/between the batteries.
The lid of the battery boxes use spaces to gap the lid up and away from the battery tops, again, allowing ventilation.

In the winter, they simply close up and latch the sides/top, slip in the bottom insulation, and the box is closed up to retain heat.

-------------------

They haven't been in service long enough yet, but I have a battery string sitting in a tank,
Enough space around/between for water to flow,
And in the winter I simply drain the tank and insert foam board for insulation.

When the water reaches a preset temp, water is allowed to flow from the well pump (Cold) to reduce the tank temp.

I don't know if this is going to greatly increase battery life, or efficiency, but I'm tracking both to see if it's worth the trouble.
I'm always looking for that efficiency edge, something that will make my system just a little bit more productive.

2. PAY ATTENTION TO DISCHARGE!
You standard 'Golf Cart' (6 Volt Deep Cycle Wet Cell) batteries can recover from about an 80% charge state (Back to 100%) with no measurable damage.
Every battery is damaged by discharge, and that damage is cumulative over time, but with common testing equipment, you won't be able to detect any serious decline in efficiency if you don't discharge past 80%

Batteries discharged to 60% will have roughly half the service life.
Batteries discharged to 50% will have roughly 1/4 the service life.

As you see, the deeper you discharge the batteries, the less service life you will have.

If you find you are discharging your batteries below 80%, then simply add another battery string to spread the load out, increase your amp/hour capacity, and keep BOTH sets above 80% charge state.

3. EQUALIZATION CHARGING.
Your batteries MUST reach 100% charge state 'In Banc',
Meaning ALL batteries MUST reach a 100% charge state fairly often.

You CAN run the battery bank at less than 100% charge state for short periods, like a week at a time,
But they MUST equalize and reach 100% charge state about once a week (or sooner if possible) if you want the longest service life out of them.

Extra panels can provide this 100% charge state more often,
Extra panels, enough to provide 100% of the home 'Idle' power, and still deliver power to the chargers will do this on sunny days.
Just a few extra panels can make all the difference...

When the sun is shining, and the home is 'Idle', not drawing a ton of power, the panels will produce enough power to 'Top Off' the entire battery bank (with charge controllers on each string),
This can give you an EQUALIZATION charge any time the sun is shining a full day and you aren't drawing a bunch of amps...

If you are a smart bunny, and you have a back up/overload generator,
Your battery chargers will try to equalize the batteries anytime your generator is running... This is depending on how big your backup generator is, and how many amps you are drawing when you run the generator....
Automatic and seamless anytime the genset runs!

4. DISTILLED WATER ONLY!
Anything else and you are killing your batteries!

There are 'Super Duper' battery 'Extender' items sold, but they are VERY short lived, and permanently kill the battery after it jumps up in production for a short period of time.
Stay away from 'Snake Oil'. I've had batteries live for more than 10 years without anything but distilled water & electrolyte recovery caps...

5. GENTLE VIBRATION.
As batteries age, they build up 'Scale' on the plates, which falls to the bottom of the battery when you equalize charge them.

This 'Scale' can build up in the bottom of the battery and reach the plates, shorting them out.
Gentle vibration will distribute that 'Scale' or 'Mud' evenly on the floor of the case keeping it from reaching the plates.

This usually isn't a problem with vehicle batteries that see vibration nearly every day of their lives,
But with batteries sitting in the same place, you will get 'Piles' of scale directly under the plate sets, so a little vibration from time to time is good for them, just don't jar the battery around hard enough to dislodge plates or crack the case.

7. DO NOT OVER/UNDER FILL THE CELLS!
There is supposed to be an air space between vapor recovery cap and liquid in the cell.
If you fill the cell up too much, the vapor recovery can't work, and when the battery heats up, you will force the electrolyte out the top of the battery.

You will normally see a plastic 'Collar' from the plug hole, extending down into the cell,
There *Should* be a slot in that collar, that slot is for vent gasses to escape.

Your 'Proper' electrolyte level is between the bottom of the collar, and the top of the SLOT......... (NOT the top of the COLLAR!)

Most people think that just keeping the tops of the cell plates covered is enough,
But you will notice that collar is a good 1/2" to 3/4" above the cell plates,
That's because the END PLATES in the cells are LONGER than the middle, stick up farther to connect to the bridges between cells...
The BOTTOM of the 'Collar' is the 'Safe Minimum' to keep those end plates covered so they don't corrode away and scale off.

8. ACID 'CREEP'.
Where the battery terminals come up through the case, there is no way to get plastic or rubber to stick to lead terminals...
So acid will 'Creep' (Capillary Movement) up those small spaces and show up on top the battery around the post.

Now, some people use wool felt 'Washers' treated with a chemical base, like baking soda that neutralizes that acid.
This is a BAD IDEA!

Since the acid is reaching the OUTSIDE of the case, picking up the acid neutralizing base, and when the battery cools,
That acid neutralizing base winds up in the end cells of the battery, killing them!

A better idea is to spray that 'Red' battery terminal protecting 'Goo' around the case to terminal crack and seal it up as best as you can.
You can also use dielectric grease to seal up that crack between terminal & case.

This way, you don't get an acid neutralizing chemical base in your acid based electrolyte...

9. GET YOURSELF SOME HIGH EFFIENCY VAPOR RECOVERY CAPS!
Most 'Golf Cart' batteries come with a 'Slosh' cap, something designed to keep the acid from 'Sloshing' out when the battery is running around a golf course.

These are NOT high efficiency vapor/electrolyte caps!

The more electrolyte you recover, the longer intervals between watering is needed,
And the less your electrolyte gets diluted over time by adding water.

*IF*...
You use an 'Auto Watering' system attached to caps,
This does NOT mean you don't have to check the electrolyte levels!

Don't trust your $250 batteries to a 50 plastic cap!
Once you get the hang of checking batteries, you can decide when your maintenance intervals should be,

But thinking because there is still water in the 'Auto Fill' cap the cell is full, that will get you a very dead battery very quickly!

I've been working on my own version for 10 years, parts from about a half dozen commercially available,
Some custom made parts, and I still don't trust them with my very expensive batteries!
They ALL get visually checked at least once a month!
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  #19  
Old 10-31-2015, 08:21 AM
OPCHARGE Male OPCHARGE is offline
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Join Date: Oct 2015
Location: Cumberland Plateau, TN
Posts: 12
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Mr. JeepHammer,
What a fantastic service you have provided. Thanks. I have also been living off grid for a while and found your works to be a great review of what I knew and I picked up a couple of new pointers as well.
You surely put a lot of time into all your writings and many will benefit.
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  #20  
Old 11-02-2015, 01:32 PM
JeepHammer Male JeepHammer is offline
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Posts: 39
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Spent 16 years off grid,
Spent 10 years owning a starter/alternator rebuilding/battery shop.
Been fiddling with 'Renewable Energy' before they had a name for it...
(Early 70's).

The most space/convenience thing I stumbled onto was batteries on carts,
Anderson connectors plugging battery carts/strings into overhead 'Mains' so any one battery cart/string can be unplugged/pulled out for service.

This allows me to leave the other battery carts/strings plugged in,
And with a charge controller for each string,
This allows me to replace any battery string without replacing the entire battery bank at once.
Rotation by string is a wonderful thing!

Bad back led to this, moving batteries is VERY difficult for me,
So I used a power hack saw, wacked off round stock in slices 1.5" wide,
Drilled them for center,
And used a common bolt for the axle.

Since these carts are going to move about 4 feet at a time,
And no more than 15 feet to the door when I swap out battery strings when they need replaced,
Having bearings isn't required.

You could make the wheels out of hardwood if you wanted to!

The carts also allow me to ventilate under the batteries.
Keeping battery temps down helps life span a bunch, so being able to get air flow under, and up between batteries is a big deal when it's hot...

On the same line of thought,
I just push the batteries together, close up the air spaces between them, to conserve heat in the winter, slap some foam board around/under/on top of them and they retain heat keeping them from freezing.

-----------------------

'Drip Trays' under the batteries, on it's own shelf, stops polluting the floor.
I use low side plastic tubs, about 8" tall on a shelf under the batteries.
They are for some kind of gardening, are about $6 each and battery acid doesn't eat them up...

The second shelves were for a second string of batteries,
But it turned out to be so low I had a hard time bending over to tend them,
So when I have 'Sweat' or drips, spill water, or a watering valve sticks open,
The trays catch the mistakes keeping my floor from degrading.

The shelves are also a good place to store the foam insulation for that battery string, the tub just sits on top of the foam.

------------------------------

Off Grid, REDUNDANCY is the name of the game...

I have my panel strings directly charging a battery string,
Each battery string has it's own panel string...
Then the excess is combined to feed the inverters.

This way, no matter what goes wrong with a panel string or battery string,
The ENTIRE system doesn't fail at once.

Since COMMON panels are wired in SERIES, on into another,
If one fails, you are SCREWED, the entire string fails.

Same with battery strings, if ONE fails, the string becomes useless.

By having 6 panel strings, 6 battery strings, I DO NOT have to buy the exact matching panels, just enough panels to power up a battery string,
Then when I expand, again, just enough to power up the battery string.
All my panels don't have to match, just like all my battery strings do NOT have to match each other.

Redundancy...

This also cuts down on the 'Combiner' box cost...
Since the combiner box IS NOT trying to handle all the panel output,
AND all the battery output at the same time,
--- With dedicated strings of panels/charge controllers/batteries,
You have already done most of the work of the 'Combiner',
The 'Anderson' connectors are your disconnects, so your 'Disconnects' are doing double duty, allowing you to pull any given cart/string with one yank on the connector,
The 'Combiner' actually only has to handle the EXCESS panel power...

I build my combiner anyway, it's just a 'Buss' with some diodes to keep your system from 'Back Feeding' bad panels or batteries,
Pretty simple stuff,
And EVERY welder repair shop has heavy service diodes in stock,
You can buy them on E-bay for cheap also...

A chunk of copper for the 'Buss', some diodes, a drill and a non conductive box (Plastic) and you are off to the races...

There are all kinds of industrial application DC fuses that are single use.
If one of my strings blows a fuse, I'm NOT going to flip it back on until I find out what failed!
DC Circuit Breakers are 'Nice', but people don't use common sense!
They like to flip that breaker back on BEFORE they find the issue that tripped it,
And QUALITY DC breakers are expensive...

When I'm setting up a system for folks new Electronics, I ALWAYS slip in a FUSE...
Keeps them from burning down the place by throwing the breakers when there is a serious issue happening...
It's SNEAKY, but it keeps them from melting their systems down!

You have to remember,
A 'Circuit Breaker' IS NOT, and was never intended to be, a DISCONNECT.
One is overload protection,
The other is to POSITIVELY, MANUALLY take the circuit off line with NO CHANCE of accidental connection...

ANY DC SWITCH IS REAL FOND OF WELDING IT'S SELF SHUT!
That includes circuit breakers...
The positive disconnect is the ONLY way to positively kill a circuit,
And the Anderson quick connectors are POSITIVE DISCONNECTS.

The lines also get a fuse or circuit breaker, but there is no substation for a positive disconnect...
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