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diy solar

How does my system look? Safe?

IHaveThePower

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Joined
Jun 4, 2022
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20220715_022035.jpg

Wondering if this setup looks OK to start closing switches.
I know two of the breakers are cheap, will they cause any problems?
Also wondering. I ran 4 gauge wire from the solar disconnect positive to the classic 150 yet the 8 gauge from the negative pv runs straight to the classic. Is this OK.
I was short on 8 gauge but I have more now so can swap that out if it's bad practice.

I have the Inverter grounded to the breaker panel, where is the best place to start a ground wire to a rod outside and is that the best way to ground the system?

I haven't connected the dc lightning arrest, is connecting it to the solar disconnect box OK?

Here are my panel specs

CS1H - 340 S
Series Hi DM
Canadian Solar

Watts (STC) 340 W

max power volts VMpp 37.8 v - x 3 - 113.4
max power current ImpP 9.0 A
open current voltage Voc 44.5 v - x3 - 133.5
Short circuit current ISC 9.57 A
Max system Voltage 1000 v
 
I know two of the breakers are cheap, will they cause any problems?

Yes. Replace them as soon as possible with name brand units. Cheap breakers often don't meet ratings. For testing purposes, it's probably fine to try with the ones you have.

Is that a 200A class T fuse?

Do you have a precharge circuit?

I'm not making any assessment of your grounding/bonding.
 
what is this all installed in... residential home? shed? enclosed cargo trailer?
 
Yes. Replace them as soon as possible with name brand units. Cheap breakers often don't meet ratings. For testing purposes, it's probably fine to try with the ones you have.

Is that a 200A class T fuse?

Do you have a precharge circuit?

I'm not making any assessment of your grounding/bonding.
It's frustrating these are able to be sold if they can't be used. I guess I'll return them

Im away right now but I'll check the 200amp fuse in a bit.
 
Fuse has sufficient AIC rating of 20,000, but that fuse is not choice. It will run for 10 seconds at 1000A when most of your other stuff has fried or ignited by then.

Class T fuses have the same AIC rating, but they blow much faster.
Thank you Sunshine_eggo
I'll do some research
Would you suggest a 200amp model as a sufficient replacement for this setup?
2x 200ah lithium
3600w Inverter on a 24v hookup.
 
Ground wire to a separate lug, probably not to a hole marked for ground (not according to UL listing of box, not that it matters for a trailer.)
More important, it is separate from the ground bar on right. All grounds should connect by wires and busbars, never rely on sheet metal enclosure as conductor (except for fault to enclosure, which conducts through enclosure to the ground connection.)
Move ground wire to ground busbar.

Is there a ground rod?

Switch with fuse - is the switch/enclosure DC rated?
If only AC rated, doesn't mean it wouldn't work for lower voltage DC, but not tested and proven.
Is the switch snap-action, or does it move slowly with handle? Obviously snap action less likely to pull an arc.
If never used to interrupt current, only isolate when inverter is drawing minimal current, then should not fail to function regardless of ratings.

Usually we would ground switch enclosure, to battery negative in this case so a fault inside clears fuse. But only if fault after fuse; before would just keep conducting. Only 24V so not a shock hazard. OCP belongs as close to battery as possible, ideally before any short is possible. What do other guys here think?

Splices in 4/0 cables to switch & inverter - are they rated for the expected current?
Make sure cables are flat on busbar, no washers in between.

Where do you bond neutral to ground?

Looks like single phase inverter to breaker panel. If you feed both L1 and L2 busbars, all breaker slots can be used.
Just don't wire branch circuits with 3 + ground cables, two lines and neutral; each line needs its own neutral. (OK to use 3rd conductor for switched branches, however.)

Is that a Delta lightning arrester on top right box?
They are a joke in the industry. Although a clamping voltage is published (a few hundred volts) I've been able to apply sine wave 7000V peak and they never fire. Maybe at some 10's of kV they conduct and clamp? Midnight has made videos comparing their own MOV with this device, which never clamped. Just metal plates inside separated by sand. "Silicon Dioxide Varistor" my @$$

 
Ground wire to a separate lug, probably not to a hole marked for ground (not according to UL listing of box, not that it matters for a trailer.)
More important, it is separate from the ground bar on right. All grounds should connect by wires and busbars, never rely on sheet metal enclosure as conductor (except for fault to enclosure, which conducts through enclosure to the ground connection.)
Move ground wire to ground busbar.

Is there a ground rod?

Switch with fuse - is the switch/enclosure DC rated?
If only AC rated, doesn't mean it wouldn't work for lower voltage DC, but not tested and proven.
Is the switch snap-action, or does it move slowly with handle? Obviously snap action less likely to pull an arc.
If never used to interrupt current, only isolate when inverter is drawing minimal current, then should not fail to function regardless of ratings.

Usually we would ground switch enclosure, to battery negative in this case so a fault inside clears fuse. But only if fault after fuse; before would just keep conducting. Only 24V so not a shock hazard. OCP belongs as close to battery as possible, ideally before any short is possible. What do other guys here think?

Splices in 4/0 cables to switch & inverter - are they rated for the expected current?
Make sure cables are flat on busbar, no washers in between.

Where do you bond neutral to ground?

Looks like single phase inverter to breaker panel. If you feed both L1 and L2 busbars, all breaker slots can be used.
Just don't wire branch circuits with 3 + ground cables, two lines and neutral; each line needs its own neutral. (OK to use 3rd conductor for switched branches, however.)

Is that a Delta lightning arrester on top right box?
They are a joke in the industry. Although a clamping voltage is published (a few hundred volts) I've been able to apply sine wave 7000V peak and they never fire. Maybe at some 10's of kV they conduct and clamp? Midnight has made videos comparing their own MOV with this device, which never clamped. Just metal plates inside separated by sand. "Silicon Dioxide Varistor" my @$$

Thank you for this info Hedges
I'm still processing it and will write back when I have a moment to work on this setup again. Life has thrown more important stuff at me.

I'm trying to get away with spending as little as possible on this setup by using some stuff I had laying around.
All cases and fuses are dc rated though from years ago I admit.

I'll order a 200amp.class t fuse at least
I don't want to make any stupid mistakes and cause a fire.
I haven't hooked up the delta arrestor. I'll search out alternatives I suppose if it's not up to the task.

Cheers
 
You can buy good assembled surge arrestors by Midnight, $150.
You can buy individual MOV as in my links below.
They can fail shorted, might burn. Some are available with a thermal fuse in series, often 3-wire for external measurement of its condition.
I ended up buying a surplus unit, which I also report testing.

 
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