What's a good PV/DC disconnect switch??

cupcake

Hi Pals!

Cupcake here again with a question for the pro's:

What's a good PV disconnect switch?

The PV input is gonna be at like 40amps max... panels are in parallel so the voltage should be 44.6 (VOC)

Im lookin to add a disconnect between roof combiner box and controller PV input...

What's a good disconnect switch for this set up??


THanks pals!


- cakemassa

Mountain Don

An MNEPV breaker by Midnite Solar. DIN rail mount. Lots of amperage choices. Cheap. Dependable.

cupcake

Mountain Don wrote: »

An MNEPV breaker by Midnite Solar. DIN rail mount. Lots of amperage choices. Cheap. Dependable.

Thanxxx

is something like this sutable? http://www.solar-electric.com/midnite-solar-mnepv-40-amps-circuit-breaker.html

Another question is the volts... the VOC of the panel is 44.6volts -- what is the correct way to ensure the breaker/switch can handle the volts?

Should I multiply the VOC volts by 1.5 or something? or no?

-- cakecup

inetdog

cupcake wrote: »

Thanxxx

is something like this sutable? http://www.solar-electric.com/midnite-solar-mnepv-40-amps-circuit-breaker.html

Another question is the volts... the VOC of the panel is 44.6volts -- what is the correct way to ensure the breaker/switch can handle the volts?

Should I multiply the VOC volts by 1.5 or something? or no?

-- cakecup

You should take the Voc as a starting point and then increase it as appropriate for low winter temperatures based on the Voc temperature coefficient of your particular panels. If you do not want to do the calculation, a factor of 1.25 will pretty much cover mainland US sites.

cupcake

Thanxx for replies so far...

Quick question:

Can circuit breakers act as disconnect switeches for DC circuits?

In otherwords if I install a breaker like this:

http://www.solar-electric.com/midnite-solar-mnepv-40-amps-circuit-breaker.html

will it suffice as a proper DC disconnect for that circuit?

Thanxxx


--icing

Vic

Hi cupcake,

You may know that you and Mountain Don linked to exactly the same breaker. These MidNite MNEPV breakers are rated for operation up to 150 VDC, and are Switch-Rated to either 5,000 or 10,000 operations (I forget which is the correct number) at full rated current. They are the real deal, and are very inexpensive.

FWIW, Vic