Hello all, I am building/designing a relay board for controlling actuator life test cycles. The relay board will supply 5-40votls and up to 30A. I am going to use some very large transistors in H-bridge formation to do this. Relay board will have a momentary 2P2T switch for when the application is not in use (processor has not signaled BJT transistors to engage motor drive) but someone needs to move the actuator a bit. This usually occurs during the set up for the life test. My question is, how do I make sure the output to the actuator is only being controlled by the switch, or the H-bridge alone, not together? I need the switch to control the motor, or the transistor through the processor, but not both at the same time. One option is to have two different connectors on the PCB, one outputs the mom switch state and the other the H-bridge state. Can I do this on one connector? My concern is that the H-bridge will be pushing a channel high, while the mom switch pushes that same channel low and shorts them out.

Thanks!

 

Sorry all, meant to have "Implimentation" in title, not "implication." lol

 

Post a diagram of what you are trying to do. I can't quite understand from your explanation how it's all connected.

 

I think he's saying he will be using hbridges to control DC actuators (forward and back) under software control.

Then he wants to use a manual switch to select between manual control or software control.

I think it would be easy enough to use a DPDT switch on each actuator to switch both wires of the actuator at once;
DPDT position 1; connects actuator to hbridge
DPDT position 2; connects actuator to a manual control