I am designing a changeover circuit that switches the load from one grid station to another. I was thinking about wiring two spdt relays in anti-parallel to create a dpdt switch.
The schematic at the end although a different application, best captures the question that I am about to ask.
My question is that can this cause a short circuit/connect the two grids during the small time period when the relay is switching. Does it matter if I am using a mechanical or a solid state relay? Is there any way to avoid this?
Best Answer
Take a close look at your motor reverse circuit. When one relay is activated and the other isn't (that is the short-time situation you are afraid of) both sides of the motor are connected to the same battery pole. With a motor, this means breaking (hard). With a normal load, this means the load does not receive any energy.
If you are realy worried about this situation, you could use a third relay to decouple your device, then switch, then re-couple it (to the switchover grid).