Disconnecting Solar Panel Under Load

[Wotname]

Originally Posted by MarkJ

I have heard such warnings and I believe them to the extent that we need to invent a thing called

A switch.


It works on every other bit of electical kit known to man. It disconnects the wires. Click. So what is the difference between disconnecting a solar panel and a switch? None.

Fundamentally you are quite correct but practically switches are a lot more complicated - at least the good ones are; cheap ones - not so much.

Some factors that go into the design of a quality switch include:

• Contact material suitable for load and type of signal
• Contact pressure
• positive "snap action" when opening to minimise arcing
• minimum (nil?) contact bounce when closing
• contacts sealed from the external atmosphere
• robust construction
• secure method of mounting
• secure method of attaching wiring to terminals

Of course there is a shipload more features to consider so while the humble switch is just another method of disconnecting wires, it sometimes is a good method

However, I'm happy to just use the connectors to disconnect a solar panel!

[Opie91]

Originally Posted by newhaul

Yes the lines would still be under load from the power the panel is producing. As I stated before and the controller manufacturers say don't disconnect the battery from the controller when the panels are producing power to the controller id: the controller is under load disconnect the panels first just don't cross the panel wires you will get a shock out of life

If you disconnect the panels from the controller, that is no load. Obviously the panels will be capable of producing energy if they are in the sunlight. Pretty sure most mc4 connectors at the panels say do not disconnect under load, so disconnecting the panels without shedding the batteries is not an option. This is where a proper "switch" comes into play.