Dazzed and confussed

[getvrtcl]

Dave, I appreciate it, THANK YOU!
So I have re read your post and I think I may of mislead you.  The system is going to be 24 volts not 12.  Does that make it more exceptable ?

[dave ames]

OH! 24 volts..

Yes that changes everything! plenty of room for all those modules and then some

Your two strings of three should work a charm!

Sorry about that..still don't see when we switched to a 24 volt nominal system..good move.

cheers, dave

[getvrtcl]

OK GOOD, I was starting to rethink things again.

[getvrtcl]

One question that I have a hard time is when I series the 3 panels X 2.  The wire on the MC4 plugs is 12gage.  When I run the leads to a box to get them together to send to the controller, what gage wire can I get away with?  The run from the box to the controller is only 22 feet.  I am 4 feet short to be able to use some left over 6 gage, what would you recommend?

[rossw]

One question that I have a hard time is when I series the 3 panels X 2.  The wire on the MC4 plugs is 12gage.  When I run the leads to a box to get them together to send to the controller, what gage wire can I get away with?  The run from the box to the controller is only 22 feet.  I am 4 feet short to be able to use some left over 6 gage, what would you recommend?

It's a fairly short run, and your current is not high.
If you already have the 6AWG there (13 sq mm or 1.261484 ohms per Km), I'd use that and extend it with either whatever you have on hand, or buy some more for the last few feet. Some internal-glue heat-shrink over the joint should make a reasonably weatherproof join.

To give you an indication - if you have 8A from each array (16A total), and 13.4 metres (22' out + 22' back = 44' run) and only used 12 AWG cable, you will see about 1.1V drop across the cable (about 17 watts).

Using 6AWG for the same run would drop only 0.27V and about 4 watts.

[TomW]

I have to agree with Ross here.

Note that you can double up cable, too. Roughly speaking if you double up one gage you get an effective gage 3 sizes larger (AWG). So 2 # 12 is equal to one #9 double those and you have #6.

If you have some romex type cable suitable for the location you can just parallel all the conductors and use 2 hunks.

More than one way to defur a feline.

Also remember that when figuring losses the actual wire  in use is 2X the run of cable.  Out and back.

Tom

[ghurd]

I was also leaning towards one of these grid tie inverters to send back any excess to the grid to lessen the pain.....  I am not sure about these "power jack" type inverters, seems a little like majic smoke to me, anyone have an opinion?

I have an opinion on that "type", based on a bazzillion emails.
They do not last long enough to pay for themselves, even when hooked up as the designers intended (plenty of smoked/smoking examples on youtube from people who thought they were great a week earlier).
The design (internally) changes faster than they can make new stickers for the enclosure, though the operational parameters remain roughly the same.
The resellers do NOT understand how they were intended to be operated, and the reseller's instructions vs. the real life operation prove this every time (so far).

The basic designs seem almost good enough to be nearly decent, but there is always a weak link.
I wish they would get the design looked at by someone who knows what is what, and where the weak links are, then maybe they could make a few changes and get it UL'd.
Then maybe they could get someone who speaks English and Chinese and Electric to make a reasonable owners manual, instead of how some ebay reseller THINKS about how it is supposed to work.

Keep in mind, send me a pile of money, and I can get a bunch for you with custom boxes, instructions, and they will say "getvertcl" on them.
It just means you spent some money.  It does not mean you know anything about them.

As far as I can tell, it is not illegal to have it, own it, or sell it.  It is illegal on several levels to actually use it as they imply it is intended to be used.
G-

[getvrtcl]

Well I end up having enough #6 to go to the combiner box from the charge controller without any splices, just moved a few things.   Trying to get the wiring done between rain storms, which brings up a good question, GROUNDING the system.  I have done a few searches and it seems to be a topic with a few different opinions.  I see some people ground the negative lead on their systems, seems to me you would be wasting electricity to ground that way.    Maybe I am missing something.

[luv2weld]

seems to me you would be wasting electricity to ground that way

I don't follow you. Can you explain how you would waste electricity???

Ralph

[getvrtcl]

I guess I can't explain it.  To me it just seems that is current returning to the negative side of a battery might go to ground instead because it is the path of least resistance. 

[ghurd]

The electrons flow in a loop within the electrical system.
There is no way for the electrons in the earth to make it in a full circle.  No power is lost or wasted.

The ground comes into play when the situation is not normal.
Short circuits.
Lightning.
etc
G-

[getvrtcl]

OK Thanks for clarifying.

[getvrtcl]

As far as everyone talking about codes and inspections there won't be any.  When I went to the building inspector to tell him what I was doing his response was "we don't like solar here, it is too complicated".
So with that said we will not have him inspect anything, its too complicated.
I want to be safe and do it correctly.

[DamonHD]

There's probably laws (local, state and federal) against that sort of attitude by Building Control (as it would be here in the UK).  %-P

If doing the job right is too complicated, maybe he should make room for someone who gives a <rude word>.

Rgds

Damon

[fabricator]

The building inspector has nothing to do with it, it's the electrical inspectors job, besides it's got nothing to do with what "they" like there, it's all about if they have an ordinance covering solar or wind if they don't you can do what ever you want, if they do it is their lawful duty to follow the ordinance, period.

[getvrtcl]

I ended up with 12 panels for a very good price.  So I will be adding 2 more strings of 3.Making a grand total of 2460 watts.

Finally got the inverter wired in on the small system for the greenhouse and wood furnace.  So far it is running like a champ.

[getvrtcl]

0

There's probably laws (local, state and federal) against that sort of attitude by Building Control (as it would be here in the UK).  %-P

If doing the job right is too complicated, maybe he should make room for someone who gives a <rude word>.

Rgds

Damon
[/quote

I agree completely, this person has no idea what he is doing.  But after talking to some around here that have done solar they all agree on one person I should call to have the system "looked" at.  I will be doing that in the morning.