Am I sizing my SCC incorrectly

rmaddy

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Cool, thanks. One more question. If an MC4 Y connector is rated 30a 1000VDC does that mean you can't exceed 30a or you can exceed it at lower voltages?
All indication I've seen is to never exceed 30A with any MC4 connector at any voltage. This won't be an issue if you only use a single pair of Y connectors to connect two parallel strings. Once you get to 3 strings or more you use a combiner box where MC4 connectors of any kind are not used at all.
 

timselectric

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I am not doing any panels in series because of the shading I am dealing with. I will have to do 4 panels in parallel and 2 SCC. I think the charge controller can't accept anything bigger 8 AWG. Maybe I need 4 SCC? My run is at least 50feet.
The panels should have bypass diodes built in, to deal with shading.
 

tony95

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All indication I've seen is to never exceed 30A with any MC4 connector at any voltage. This won't be an issue if you only use a single pair of Y connectors to connect two parallel strings. Once you get to 3 strings or more you use a combiner box where MC4 connectors of any kind are not used at all.
Okay, I guess I can drastically shorten my runs by putting my SCCs on the side of the house closest to the panels. I was planning to put them under my server room opposite the wall closest to the panels, but probably makes more sense to have a longer single 12 gauge AC run into the server room then several 6-8 gauge runs across my basement.
 

rmaddy

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Longer AC runs are usually better than longer DC runs since the AC runs are usually higher voltage therefore resulting in less voltage drop.
 

tony95

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Longer AC runs are usually better than longer DC runs since the AC runs are usually higher voltage therefore resulting in less voltage drop.
Yes, especially when you only need one versus two.
 

timselectric

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Okay, I guess I can drastically shorten my runs by putting my SCCs on the side of the house closest to the panels. I was planning to put them under my server room opposite the wall closest to the panels, but probably makes more sense to have a longer single 12 gauge AC run into the server room then several 6-8 gauge runs across my basement.
SCC, is also a DC output. And it's at a lower voltage, so affected by voltage drop even more. Unless, you are also planning to move your inverter . And batteries, if batteries are part of the plan.
 
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