timselectric
If I can do it, you can do it.
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My point exactly.
3/0 was following your theory.
Grounding Correct? Or Not?
- Thread starter LSC
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3/0 was following your theory.
timselectric
If I can do it, you can do it.
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MichaelK
Solar Wizard
Are your purposely trying to cause confusion? That is really unprofessional.
timselectric
If I can do it, you can do it.
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Absolutely not. I'm hoping that the OP gets the correct information. Electricity is dangerous, if improperly installed.
Every reference I have to awg of earth grounds list minimal 8 gauge. You are dealing with 25 AC amperes. 8awg will be fine, larger will not hurt. When you are plugged into the grid, your earth grounds must go to the main panel earth ground. That you have. When you are disconnected from the grid, all AC current references back to the inverter case. That you have.
At 24 volts you should be fine with 1/0 awg marine grade cable. That will carry 285 DC Amperes. You need better fuses than ANL for main battery fuse, and closer to battery positive. Fuse to protect the wire. I would fuse 1/0 marine grade wire at 250 amperes. Not those 100 amp ANL.
The purpose of grounding the solar panel frames is for lightning protection. That earth rod should not connect to the equipment. I am open to correction of this, just give me a link to relative national electrical code.
Controversial on internet-->There must be only one earth ground when connected to the grid. Do not connect the equipment to that rod.
At 24 volts you should be fine with 1/0 awg marine grade cable. That will carry 285 DC Amperes. You need better fuses than ANL for main battery fuse, and closer to battery positive. Fuse to protect the wire. I would fuse 1/0 marine grade wire at 250 amperes. Not those 100 amp ANL.
The purpose of grounding the solar panel frames is for lightning protection. That earth rod should not connect to the equipment. I am open to correction of this, just give me a link to relative national electrical code.
Controversial on internet-->There must be only one earth ground when connected to the grid. Do not connect the equipment to that rod.
Thanks, I will change the main fuse to the inverter from the battery to a 250A T fuse. Why so high? Protecting the wire if I remember correctly. Yes?
I would assume that the ACIN, ACOUT and PV wires as well as the ground wires should also be 8 awg?
Okay, so connect the panels to that rod but not the units grounded to each other inside? They should be grounded to just the ACOUT ground, yes?
timselectric
If I can do it, you can do it.
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timselectric
If I can do it, you can do it.
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Here are a few links for fuses & fuse holders:
www.amazon.com/gp/product/B0017SJOH4
www.amazon.com/gp/product/B0753HBG6N
www.donrowe.com/TFB2-250-250A-Class-T-Fuse-Kit-p/tfb2-250.htm
www.donrowe.com/category-s/1845.htm
Here is a link for 10 AWG solar wire. Wire for Solar Panels often have long runs and 10 AWG will have less losses than 12 AWG. This type of wire is needed for outdoor use. Many wire sheathing cannot stand up to the sun and will fall apart.
www.amazon.com/gp/product/B08ML4RP85/
Hope it helps...
www.amazon.com/gp/product/B0017SJOH4
www.amazon.com/gp/product/B0753HBG6N
www.donrowe.com/TFB2-250-250A-Class-T-Fuse-Kit-p/tfb2-250.htm
www.donrowe.com/category-s/1845.htm
Here is a link for 10 AWG solar wire. Wire for Solar Panels often have long runs and 10 AWG will have less losses than 12 AWG. This type of wire is needed for outdoor use. Many wire sheathing cannot stand up to the sun and will fall apart.
www.amazon.com/gp/product/B08ML4RP85/
Hope it helps...
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I love the comment at the end about #6 grounding wire size being absurd
MichaelK
Solar Wizard
Since I was contradicted for what I stated in post #11, here is a reference for that....
homearise.com
Does ground wire have to be the same gauge?
The answer is yes. The ground wire, hotwire, and neutral wire should be of the same gauge. Because the gauge size is determined by the load current. Neutral wire returns the same load current in hotwires. For that reason, the wire size has to be the same. But for the ground wire, the size can be bigger and smaller sometimes.
Does Ground Wire Have To Be The Same Gauge? [Explained] - Home Arise
Does ground wire have to be the same gauge? Some say it does. But does it really have to be? We’ve discovered the answer for you. Read along to know the answer...
homearise.com
Does ground wire have to be the same gauge?
The answer is yes. The ground wire, hotwire, and neutral wire should be of the same gauge. Because the gauge size is determined by the load current. Neutral wire returns the same load current in hotwires. For that reason, the wire size has to be the same. But for the ground wire, the size can be bigger and smaller sometimes.
timselectric
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Generally on circuits below 30 amps. The ground wire size matches the current carrying conductors. That's just how it works out in the table. But, this doesn't always apply. So, it's best to check the tables for each situation.
Don't confuse "ground wire" used meaning dc negative. Very true, negative and positive must be same gauge.
Then there is "ground wire' used meaning the earth ground in an alternating current. The neutral and hot are the same size and the ground in a circuit (think romax) is not always the same gauge. Not always and not necessary as it serves to trip the breaker while transfering momentary voltage to earth. But the general system ground that connects eventually to the earth ground is larger gauge, as noted above in the chart.
Then there is "ground wire' used meaning the earth ground in an alternating current. The neutral and hot are the same size and the ground in a circuit (think romax) is not always the same gauge. Not always and not necessary as it serves to trip the breaker while transfering momentary voltage to earth. But the general system ground that connects eventually to the earth ground is larger gauge, as noted above in the chart.
Wow, those are intense and even the guys talking don't always agree on what is the correct way to grounding or bonding. See what I mean. Thanks for the link. I am still confused on my ground rod. They showed a pic of a house with an array connected to a ground rod and the path lightning can take. Ouch. So what to do?
I am using those exact fuses, so thanks for the links.
timselectric
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So my only question now is that
I agree. So do I run the 6 awg wire from the array to the combiner box and then 6 awg from there to the ground lug in the ACin breaker box?