Optocoupler Isolation do I need it?

[alvise mj]

I was wondering if for extra safety is a good idea to have a Optocoupler to drive the remote control of your load and chargers , in particular Victron Multi Plus chargers and the inverter side , solar DSSR20, I am also planning to use a Victron Energy Battery Protect 12/24-Volt 65 so i can use the control port to disconnect the load.

last but not least if you want to haven all your loads on or off at the same time can you connect your control in  parallel on your EXTIOx port , or maybe in this case is when you want to use a Optocoupler and jump the signal on one side and separately control all your controls on the other side? (i have e sketch but not allowed to upload image or file :( )

[Dacian Todea]

The EXT IOx on the SBMS0 are already opto isolated with the Toshiba TLP172GM

But if you need to control more than 4 devices that have different incompatible type of remote then yes you can add external optoisolators to keep the devices separate.

EXT IO3 for example is setup by default as type 2 so to control Loads and so you can control say 1 or more Battery protect but if you want a battery protect and a Multiplus then they have different type of remotes (I think multiplus is just 5V so it will get possibly damaged if paralleled with the Battery protect and it will not even work as others have tested) then you need to have two optoisolators one for the BP65 and one for the Multiplus and the inputs of those optoisolators will be both controlled by the EXT IO3.