Panasonic HIT solar on sale

[longhorn]

Originally Posted by StowawayJoe

Thanks, but I meant which brand/model DC breaker did you use. The ones I've looked at were only rated for 48 volts. The Panasonic panels have an open system voltage of 69.7 and a max output voltage of 58

I did find these that claim to be rated for 72 volts

https://www.amazon.com/gp/product/B0...0?ie=UTF8&th=1

MidNite Solar has DIN mounted DC breakers. They have two models, one for 0-150v and the other for 150-300v.

[Dsanduril]

What is the point, with only two panels, of installing a breaker between the panels and the controller? The panels can only generate their own Isc (short-circuit current) so a short at the panels can't really trip a breaker. Breakers on the output side of the controller make sense, but on the input side they only make sense with larger arrays where inter-panel currents could exceed the Isc of a single panel. But then they have to fitted to prevent inter-panel flow.

A DC switch is much easier to come by and serves to disconnect the panels from the controller if that is the aim.

[StowawayJoe]

Originally Posted by Dsanduril

What is the point, with only two panels, of installing a breaker between the panels and the controller? The panels can only generate their own Isc (short-circuit current) so a short at the panels can't really trip a breaker. Breakers on the output side of the controller make sense, but on the input side they only make sense with larger arrays where inter-panel currents could exceed the Isc of a single panel. But then they have to fitted to prevent inter-panel flow.

A DC switch is much easier to come by and serves to disconnect the panels from the controller if that is the aim.

low amps, but high voltage. Panasonic panels = voc=69.7v vpm=58v
you're correct no breaker needed, but they're a lot cheaper than high voltage dc switches.

[Dsanduril]

For two panels (parallel) = 13A Isc you can pick up a 15A IP68 toggle switch like this one that's rated 250VDC for $12. If you don't care about the IP68 rating you can get one for half that price. For bigger arrays it does become more difficult, once you get above the 15A rating things do start to get expensive and the breaker may be cheaper.