Crut's version of overlap protection has an R-C delay network at each driver transistor gate of base.

Why do you think adding a MOSFET to do that is preferable to adding my network, which would add only two more diodes, resistors, and capacitors?

 

I have a query about how to switch on and off 3 devices using relays or similar and where one of the device states is quiescent or temporarily not in use.

The table below shows the sequence of events I'm trying to arrange electronically.

View attachment 303355

Is it possible to run this series of states in sequence going round and round, perhaps with a timed duration between each step using a series of relays (and a timer circuit)? It’s twisting my head up in knots a bit trying to figure out how to do it and perhaps one needs two sets of three relays and a way to link them together.

I’m also aware of these Wi-Fi-based modules, as in the pic, that can remotely route one of several inputs to an output, e.g. for home IOT-type events but I don’t think that quite does it for this scenario.

View attachment 303356

I would be interested to hear anyone’s ideas.

Justin

Are the three devices you want to turn on, turn off and charge 120AC devices? It sounds like they are battery powered because of the need for a charging source. Can you provide more detail about the devices you are trying to turn on, turn off and charge?

 

I realize that you want to turn the devices on and off individually. This sketch does not quite do that as all are on, all are off or all are charging. This also assumes the devices use 120VAC with some down regulator:

Is this similar to what you had in mind?

 

I have explained earlier why a Microprocessor is not the way I need so I guess you missed that;

If you had the time, you could issue the same project but WITH a microprocessor. Or it could be for extra credit.

 

But Nandu beat you to it.

grrrrrrr