High Voltage DC Switch Source for Solar

CA Traveler wrote:
I need a high voltage DC rated switch for 3 series connected solar panels. The panel ratings are Voc 37.45V , Isc 8.7A, so I’ve been looking for a DC switch rated at 125V and 10A. If there is a simple SPST switch for this application I haven’t found it... ...Alternatives or suggestions?

Alternative - If you want a switch and not a circuit breaker, how about using a solid state switch and controlling it with low voltage? Your control could then be a standard panel mount mini toggle switch or equiv. If you need to fuse it, do that separately, in series with the switch. Extremely low parasitic draw, and cheap.

Something like this for $25.

Certainly night time disconnects solves any arcing problem. A fuse would certainly work, however, I don't want my hands any where near any metal contacts because of the high voltage.

Hi,

If you can wait until the sun goes down arcs won't be a problem.

For ten times per year I'd look at a fuse.

DrewE - Interesting DC disconnect switch and certainly a good price. I briefly read about their mechanical/hydraulic operated CBs. Maybe a latching solenoid which would have no draw if one was available...

Wiz - Yes arching is the issue with DC. I agree that a AC switch can be used but was surprised with the limited selection of DC rated switches for higher voltage at reasonable prices. In fact I have wired in a cheap 2 pole A/C disconnect switch for both of the panel wires but ideally would like a better quality switch. I'll be turning off the controller about 10 times/year for maintenance and for covered rig storage with no power and full battery disconnects.

atreis - I have a friend that uses one of these on 4 panels connected series/parallel about 60VDC. I suspect that switch is rated for 48VDC.

YC1 - Both actually. 3 series wired panels at over 100VDC and 8A+ connected to a MS MPPT 60 solar controller with 12V batteries. There is a remote possibility of adding another panel with series/parallel wiring for 70VDC at 17A. Due to the high voltage and lack of ground reference I'd also prefer a 2 pole switch.

The controller and related wiring is installed. Solar panels soon.

I did get some offline input from another poster which helped expand my search. And thanks to everyone.

Just to be clear, are you actually connecting them in series to produce over 100 volts DC? Or are you using them in parallel through a regulator to produce battery voltages?

It's probably overkill, but these are very nice switches (Blue Sea - Amazon).

assuming your thinking of heavy arcing ?
how often do you intend to actually use the switch, for what purpose
to occasionally disconnect the solar panels from the controller
if this is only going to happen for maintance
and will normally be closed aka ON most of the time
just get a normal 20amp 120v spst toggle, they even make 20amp LIGHT switchs for wall plates.. no need to worry about a special DC switch, if its not going to be switched on-off every day

125VDC 10A circuit breaker here for $13

Various power tap switches (only some are DC rated) for various prices

Maybe a relay with suitable contacts would be easier to find than a switch if you can put up with having the parasitic power draw in either the on or the off position.