Just wanted to make sure I got this right, according the calculators like this 1/0 should work up to 250A given it's open air, correct? And this should be the cabling all the way to the inverter not just to the fuse, right?
1st off-grid adventure — need charge controller advice
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Hedges
I See Electromagnetic Fields!
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All wires in a loop from battery, through fuse, to inverter, from inverter back to battery.
With that calculator, it says 1/0 assuming 120V and 90C, open air.
Using 48V (your battery?), it says 3/0 due for 1% voltage drop over 10'. Or 1/0 for 3% voltage drop.
But that is at 90C. The wire would be OK (but too hot to touch, 65C considered reasonably touch-safe.)
However, what are terminals of fuse holder and inverter rated for? Likely 75C. Then it says 2/0.
Of course you're not actually running that 1.25x margin meant to avoid nuisance trips. So we can get away with bending rules a bit at least if not reviewed and inspected.
But having very short and fat wires helps inverter deliver surge current to start motors, 5x what it draws running.
With that calculator, it says 1/0 assuming 120V and 90C, open air.
Using 48V (your battery?), it says 3/0 due for 1% voltage drop over 10'. Or 1/0 for 3% voltage drop.
But that is at 90C. The wire would be OK (but too hot to touch, 65C considered reasonably touch-safe.)
However, what are terminals of fuse holder and inverter rated for? Likely 75C. Then it says 2/0.
Of course you're not actually running that 1.25x margin meant to avoid nuisance trips. So we can get away with bending rules a bit at least if not reviewed and inspected.
But having very short and fat wires helps inverter deliver surge current to start motors, 5x what it draws running.
Zwy
Solar Wizard
Just hold the push button until the light dims. No need for automation. You have to manually trip the breaker or switch anyway.
If I'm playing with a cap that has been charged, I use a screwdriver to short across the terminals.
Zwy
Solar Wizard
I would say that cap was defective.
I need some help getting the wires into my garage, I am kinda both lost and a little scared since it's punching a hole into the house.
First, do I need to run cables inside a conduit? Initially/for a while, this will be a temporary install with the panels laying on the grass (more on this later — need to angle them a bit), so location of panel-end wires isn't necessarily fixed. They will then run along the top of my wooden fence and then somehow into my garage. Just to test I could run them with the garage open, but this isn't an option for more than a few hours, I would then need to take the wires out to close the garage. This is of course highly impractical, although I will probably do it once just to test that I've got things working.
Back to conduit.. given that it's not a very permanent install, I'm thinking of just running the wires.. But then thinking that they will be initially be carrying ~100-135V @ 22A and eventually closer to 300V @ 11A makes me a bit uneasy just running them "in the open," although the plan is to run them along the top of the wooden fence, and then along the top of the garage wall, only dropping down to where the PV disconnect and CC is. Thoughts on conduit?
Now, the bigger question is, how do I run them inside, easiest/less damaging way? I'm not at all excited about making holes in the wall, as I have zero experience with it. I am concerned about making the hole, running whatever's gonna go between the outside to the inside (assuming another piece of conduit? maybe an upside-down U somehow?) and water sealing it. Any help would be appreciated. I can draw a diagram of the layout of where the panels will be, wooden fence and where my garage is, and where the breaker/CC will be in it (any suggestions for software to do that?).
First, do I need to run cables inside a conduit? Initially/for a while, this will be a temporary install with the panels laying on the grass (more on this later — need to angle them a bit), so location of panel-end wires isn't necessarily fixed. They will then run along the top of my wooden fence and then somehow into my garage. Just to test I could run them with the garage open, but this isn't an option for more than a few hours, I would then need to take the wires out to close the garage. This is of course highly impractical, although I will probably do it once just to test that I've got things working.
Back to conduit.. given that it's not a very permanent install, I'm thinking of just running the wires.. But then thinking that they will be initially be carrying ~100-135V @ 22A and eventually closer to 300V @ 11A makes me a bit uneasy just running them "in the open," although the plan is to run them along the top of the wooden fence, and then along the top of the garage wall, only dropping down to where the PV disconnect and CC is. Thoughts on conduit?
Now, the bigger question is, how do I run them inside, easiest/less damaging way? I'm not at all excited about making holes in the wall, as I have zero experience with it. I am concerned about making the hole, running whatever's gonna go between the outside to the inside (assuming another piece of conduit? maybe an upside-down U somehow?) and water sealing it. Any help would be appreciated. I can draw a diagram of the layout of where the panels will be, wooden fence and where my garage is, and where the breaker/CC will be in it (any suggestions for software to do that?).
Zwy
Solar Wizard
I run PV wires in pvc conduit outside, SCH80 on anything above ground. Inside a structure, it is required to be metal. Either EMT or MC works for me.
For a transition between pvc and conduit, mount a junction box on the outside wall, then exit using EMT/MC thru the backside into the structure.
For a transition between pvc and conduit, mount a junction box on the outside wall, then exit using EMT/MC thru the backside into the structure.
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