diy solar

diy solar

Very first off grid diy solar system initial set up Q!

So that would put it inside the combiner box, or right at the "Y" cable if used instead of a box.
She has too many amps for any of the Y cables that I have seen (mostly up to 30a from my recollection).
So that would pretty much mean she needs a combiner box. You mention "inside the combiner box".

Is that something that exists as stated or would one need to add the fuses to a combiner box? (asking for a friend).
 
Combiner boxes typically have a DIN rail for breakers or fuses, so that would be inside the box.
Sometimes pre-assembled, often sold empty to be configured as needed.


MC4 is typically rated 30A, and some "Y" cables are made with 8 awg. Unless it had a special MC4 connector rated 55A, and you were sure the mating cable also had a compatible MC4 connector of same rating, couldn't rely on MC4 to carry the combined current.

I think if you got a 4-Y cable, or three 2-Y cables, you could just cut off the MC-4 connector which would have had to carry the combined current and splice it to the home-run wire. Put four MC-4 fuse holders on the Y cable and connect to PV panels.

MC4 fuse holders aren't touch-safe but the MC4 connectors are, so disconnect both MC4 cables before opening. Interrupt current flow before disconnecting, so not under load.

I think I've heard that new/future requirements are that PV breakers be non-polar? If so, that solves my concern that the polarized ones can't actually provide the protection they were supposed to. A 4-pole breaker (all poles ganged) would work fine even if polarized. Fuses are good, but don't serve as a disconnect under load. Four touch-safe fuse holders and a breaker as disconnect would work, or shut off charge controller by opening breaker on battery side before opening fuse holders.

This is the one I wouldn't trust unless the breakers were non-polarized, or had a wire slipped through the handles to gang them. I haven't heard of any faults that they should have interrupted and didn't, just expressing my opinion/analysis of the breaker ratings and required performance.



Prices on those all seem high, but vary from difference sources. It is the breakers and fuses themselves which particularly need to have the right voltage/current/polarization specs.
 
Hi again! So we’ve been hard at work putting it all together.

Everything has been connected and is working except my all in one Inverter charge controller keeps giving me an error. It's error code come up as ( battery equalization immediately) apperently there are two options? Stop equalization or start equalization...... Does anyone have any advice to help me solve this problem?

Just a quick run down on final set up:
The system is a 3000 watt all in one Inverter ( manual https://www.amazon.com/clouddrive/share/G5VlymTxFRpNv9XvOwzNiYO7No3QQ879dFjAPOoiUqD) at the moment we have 4 12 volt lead acid deep cycle batteries, set up in 24volt configuration. When I turn the inverter on and the batteries on there is no problem but once I turn the solar panels on this error code comes up. On the roof I have 8 panels in 4 series which draw 65 volts each. All my wire sizes are correct and my runs are not very far.....
 
Since this is just an initial set up issue I don't think it matters too much. Perfectly OK to let it run an equalization sequence or to say no.
 
have 8 panels in 4 series which draw 65 volts each.
In you original post, i see a solar panel spec label and it says the Voc is 37 volts. 4 in series is 148v (at 25 deg C). Any colder and its over 150v pretty quickly.

The SCC label says 100 volts max input voltage. You are fortunate if its just throwing an error code and not hurting anything with excessive voltage from your array.
 
What battery?
FLA which can tolerate equalization, or AGM which can not?
If FLA, check all voltages and maybe specific gravity out of curiosity and you could let the system do what it wants.
If AGM, change battery type setting or change equalization voltage to "do no harm".
 
In you original post, i see a solar panel spec label and it says the Voc is 37 volts. 4 in series is 148v (at 25 deg C). Any colder and its over 150v pretty quickly.

The SCC label says 100 volts max input voltage. You are fortunate if its just throwing an error code and not hurting anything with excessive voltage from your array.
I’m sorry my solar vocabulary is probably inaccurately said
We have 2 panels in series four times each running 64 volts each

Also forgot to mention that we do have a combiner box it is a modified homeline QO rated for dc interior electrical panel purchased at home depot - i have the corresponding fuses which are breakers which are 15 amp breakers from there it legs over to the inverter with a 8 awg wire.
 
I’m sorry my solar vocabulary is probably inaccurately said
We have 2 panels in series four times each running 64 volts each

Also forgot to mention that we do have a combiner box it is a modified homeline QO rated for dc interior electrical panel purchased at home depot - i have the corresponding fuses which are breakers which are 15 amp breakers from there it legs over to the inverter with a 8 awg wire.

That fixes the Voc concern.

"interior panel", so your PV combiner box is in a dry location?
"modified"??

Do you use 2-pole QO breakers? With both poles interrupting they are "Square D Certified" for 125VDC. One pole they are UL listed for 48VDC.
(Not that it is necessarily likely to fail with one pole and 65V, just not rated for it.)
 
When I put my multimeter to the PV inverter connection it is reading 63.5 volts

Also when the PV input is on and the battery is turned off the error code 3 which reads ac input range comes up. These two things may not be related but ...
 
I’m sorry my solar vocabulary is probably inaccurately said
We have 2 panels in series four times each running 64 volts each

Also forgot to mention that we do have a combiner box it is a modified homeline QO rated for dc interior electrical panel purchased at home depot - i have the corresponding fuses which are breakers which are 15 amp breakers from there it legs over to the inverter with a 8 awg wire.
could you post a link to your batteries.
equlazation destroys some battery chemestries..
 
That fixes the Voc concern.

"interior panel", so your PV combiner box is in a dry location?
"modified"??

Do you use 2-pole QO breakers? With both poles interrupting they are "Square D Certified" for 125VDC. One pole they are UL listed for 48VDC.
(Not that it is necessarily likely to fail with one pole and 65V, just not rated for it.)
Everything is in a dry spot
No, we have 4 single pole 15 amp breakers..
 
Those won't be damaged by an equalize, but it does make me wonder. If they are new batteries they shouldn't need it. They are rated at 101 amp hours, so try not to pull more than 50 amp hours out between charges. That seems a good price BTW.

A suggestion for next time is to ask them to fully charge them for you.
 
Our system does not seem to want to work.

I was mistaken as the inverter doesn’t actually give me the option to equalize or not it just says do one or the other without any ability to change settings...

The current status:

The combiner box is a square D QO panel with 4 single pole Square D QO 15 amp breakers.

Currently we have 4, 12volt batteries. Connected in pairs making 24 volts. They are brand new.

All the wiring is the right size.

We have a switch to turn off the batteries.

All the voltage on the panels is good as is the voltage on the batteries, and the polarity is correct.

What happens: once everything is connected I flip on the on switch, then the batteries, then the combiner box breakers. Everything runs for a minute then it shuts down with a fault code.

So I try to run it only on batteries by disconnecting the combiner breakers..... It works fine. It runs the cabin on the batteries no problem, no error, no interruptions.

Next I decide to skip the combiner box. I wire one of my panel pairs directly to the inverter, skipping the combiner box. Now it runs.... For about 10-15 minutes no trouble.... But then it cuts off. I test it and I see that as soon as I turn it on the voltage starts dropping slowly. Finnaly when the voltage is too low, it cuts off. So I disconnect the pv panels from the all in one Inverter and the volts automatically go right back up to 65 volts......

Why is the voltage being throttled?

Do you think the inverter is bad?

It gives me two separate error codes. When I turn on the batteries then the PV panels it gives me a code "battery equalization immediately" but it does not offer me a prompt to do this and if I run the brand new batteries with out the pv panels I don't get any code for the batteries.

Next if I turn on only the panels I get a different error code. I get error code "AC Input Voltage Range" ... It does not give me any options but when I read the manual it says it could be " Wide mains input Voltage range 90-140k” Or " Narrow mains input voltager range 90-140v but I have no AC Input wired in at all. It's totally off grid..

The only input it's getting is a 65volts from the PV panels. And the Batteries.

I have no idea what the problem is, why I'm getting odd conflicting codes, and why when I run only two panels does the voltage just keep dropping. I'm thinking that the all in one Inverter (that came with scratches on it) is probably bad..... What do you think?

I’m trying not to give up ??? thank you all for your help you guys are amazing
 
4 single pole Square D QO 15 amp breakers.
If those breakers do not say DC, there is a risk of fire when going live. AC breakers shut off much differently than AC does. Has something to do with the phase shift that I don’t quite understand how they trip, but I do understand the YouTUbe videos of AC breakers catching on fire with DC run through them.

Here’s one of the entertaining videos:


I do not know if this could cause your problem. To test if your circuit breakers are causing you the issues, I would remove three strings of your 2S4P set up and connect just one set of panels in 2 series connection directly to your SCC or inverter charger.

Using SCC to test
==============

I only mention this because a PWM SCC from Amazon can be purchased cheaply and delivered to your door the next day. This will not power your system but would let you know if your inverter charger or SCC is bad or misconfigured.

Another way to test this is to have a SCC connected to the solar panels and battery to see if the batteries charge correctly. If that works that points to your inverter charger or SCC being bad from the box or improperly configured. PWM SCC controllers are cheap, but you need to match these to your batteries and solar panels. If your panels are 37 volts, you may need to configure you batteries to 24 volts and your panels 2 P.
 
Hey all!!! We ended up returning the cheaper inverter off amazon and got the growatt 3k all in one.. we have been in business!!!! Thanks for all the help we really couldn’t do it without it! Feeling grateful for harnessing sunlight successfully!! ?

As for the next additional project to our system- I can’t see to find information on conecting a gas power generator to the ac input. We have rainy days coming and I want to be able to charge my batteries. My growwatt all in one instruction manual does not detail how to connect a generator. Do I just use a 12 gage extension cord? Do I just wire that into the growatt inverter?
 
12 awg is for 20A, 2400W at 120V or 4800W at 240V. Possibly you would want a 10 awg 30A cord.
I haven't used that inverter, but see if there is a setting for how much current it should draw from the input. It may be able to let you connect a smaller generator, draw no more than your setting, produce additional power from battery when needed.

Do you have a generator yet? Dual fuel would let you use propane (never goes bad like gas), tri-fuel would also use natural gas, cheap and convenient if available at your house. Some are electric start and some inverters can automatically start and stop generator.
 
My growwatt all in one instruction manual does not detail how to connect a generator. Do I just use a 12 gage extension cord? Do I just wire that into the growatt inverter?
In basic form yes. Need to post the charging capability and generator wattage to confirm details.

Need to be aware of keeping the generator exhaust away from the structure to prevent CO issues.
 
Hey all!!! We ended up returning the cheaper inverter off amazon and got the growatt 3k all in one.. we have been in business!!!! Thanks for all the help we really couldn’t do it without it! Feeling grateful for harnessing sunlight successfully!! ?

As for the next additional project to our system- I can’t see to find information on conecting a gas power generator to the ac input. We have rainy days coming and I want to be able to charge my batteries. My growwatt all in one instruction manual does not detail how to connect a generator. Do I just use a 12 gage extension cord? Do I just wire that into the growatt inverter?
Depends really on your generator. If it is under 2000 watts, it would usually just have a regular run of the mill plug. That would work well with a heavy duty extension cord, i.e. 12 gauge copper.

Once generators get above 3000 watts, they normally have two regular outlets, and an RV outlet. Two different ones there, 30 amp and 50 amp. Unless you are spending big money on the generator, my bet would be the 30 amp.

Regular 12 gauge extension cord install:


For the higher amp plugs, you would use a different extension cord.


Make sure what type of plug your generator has first, and how many watts it is rated for. Then select the extension cord and wire it up.
1800 watts (15 amps at 120v) is your normal wall plug in the USA, some may be wired for 20 amps, they have a slightly different plug.

plugs.jpg


This is the type of plug I use with my 3400 watt generator:

 
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