PV disconnect switch, Victron SCC grounding and more

[sunrise]

In my small trailer solar (240w, in parallel) setup, I have a 20A auto-reset thermal breaker and a 32VDC switch between PV and a Victron SmartSolar 100/20 SCC. I want the switch so I can disconnect PV when it's not needed so it doesn't keep my battery at high SOC. I thought this was fairly common, AMSolar even have this kind of setup diagram on their website:

Charge Controller Kits

RV Solar Panel Controller - At AM Solar we have RV Solar panel controllers and RV Battery charge controllers.

amsolar.com

Yesterday I came across this video and now I am a bit confused and concerned if this is the right thing to do:

I am wondering when my switch is disconnected, if the floated negative wire from PV to SCC could damage the SCC or cause other problems? The Victron SCC has separate negative connectors for PV and battery, and there is a grounding screw on the SCC heatsink but I did not connect the grounding screw. Also my 12v panel ground busbar has a copper wire that is screwed onto A frame.

Thanks in advance!

 

[HRTKD]

I went the dual-pole circuit breaker route. Is yours wrong? Probably not. As long as you can switch it off, that works. However, an auto reset breaker doesn't sound like a switched breaker to me.

Do you have a breaker between the SCC and the battery? If not, you may want to add one there. That allows you to turn off the SCC. If it's still connected it will draw some power from the battery. A small amount, but still a draw. If you add this breaker, be sure to turn off the solar breaker first, then this breaker. To resume use of the SCC, turn the breakers on in the reverse order. SCC/battery first, solar/SCC second.

 

[sunrise]

Thanks @HRTKD, I have both auto-reset breaker and a 32vdc marine switch between SCC and PV.
I also have a 25a breaker between SCC and the battery.

What will happen if I disconnect the battery from SCC first?

 

[HRTKD]

Thanks @HRTKD, I have both auto-reset breaker and a 32vdc marine switch between SCC and PV.
I also have a 25a breaker between SCC and the battery.

What will happen if I disconnect the battery from SCC first?

Supposedly, it is hard on the SCC. Most manufacturers say in their manuals to disconnect panels first, then battery. This is the method that I follow every time.

However, Will posted his test and it sounds like the order may not matter. See link below. Nonetheless, I will continue to disconnect the panels first.

Trying to destory my SCC's: I can't do it!

So I took every EPEver/Victron/PWM/Renogy solar charge controller, and tried to fry it by connecting it only to solar panels, and not to a battery... guess which one survived? EVERY SINGLE ONE! I couldn't destroy any of them, and I left them connected to a high voltage array (80 volts) for 4+...

diysolarforum.com