PV power disconnect

jumandda

I have an small experimental/ emergency backup solar system.

2-  REC 325W (24v) panels
1-  Victron 100/50 MPPT
2-  6V 210AH batteries

panels are 24V, wired in series at 48 volts

with the higher voltage (in full sun almost 80 volts) I don't disconnect under load (cover panels with blankets if needed).

What is a decent way to disconnect when there is load?


Choices:
battery disconnect switch.  are my volts too high?
standard 120V light switch.

Low-voltage Miniature DC Circuit Breaker, Din Rail Mount?

if so, single pole or dual pole?
with my 48 (80) volt, 650W system, best amperage value?

my thoughts so far:

2P 250V Low-voltage DC Miniature Circuit Breaker For Solar Panels Grid System Din Rail Mount 16A

I already have an inline blade fuse on the exposed positive lead, I never have exposed wires without some protection.

Thanks all,

Jim

mike95490

I ran my power into a breaker box, and used 150VDC rated breakers to control things

MichaelK

The standard 120V light switch would be a VERY bad choice.  It's designed for AC, which arcs much less readily than DC does.  What can happen is that went opening the circuit, the DC current can arc across the small gap, welding the metal together.  DC rated breakers separate the metal connections much further apart, reducing the danger of arcing.

Vic

You will need a DC rated breaker,  which will provide protection for the cables,   and is rated  to act as a switch at its rated current.   One like this:
https://www.solar-electric.com/midnite-solar-mnepv-15-amps-circuit-breaker.html

This is about the smallest USEABLE box for the DIN Rail breakers:
https://www.solar-electric.com/misobigbabox.html

The above is s DIN Rail mount.  There is another MidNite breaker series,  is a Panel Mount.  These are MNEDC series.    Here:
https://www.solar-electric.com/search/?q=mnedc++15

Here is a small box for MNEDC breakers:
https://www.solar-electric.com/mnedc-quad.html

The breaker that you linked to,   is NOT rated for use in DC circuits.

There are some other details,   Be certain to have a DC breaker (or perhaps a suitable fuse)  on the connection from the Charge Controller and the battery.

FWIW,   Vic