Digital ON/OFF 230V AC Equipment

Hi friends!
I need help in controlling 230V AC device working at 40 Amp maximum current. The device will remain ON most of the time. I want to remotely switch it OFF for 6-8 Hrs and then Switch it ON. ON Time is more than OFF Time. I want some Solid state solution to control it using Digital Logic (TTL/CMOS). I don't want to rely on Electromechanical Relays unless they will be very good in performance and life.

Any idea??

Bye!
Sunil Jha

You can easily find SolodState block that will handle 40A.
You have to deliver 5-30V (usually, approx. @10mA) to turn it ON
Please be more specific on "remote control"

Are you sure you don't want to just use a relay, it may be a nice easy way to do it. especially if you are only switching once every 8 or so hours.

It could be a simpler solution than using TRIACS / SCRs to switch 40A @230V (Thats a decent amount of power).

What type of load are you planning to run? Inductive / Resistive /etc., this will influence the design difficulty.

As the OP says, you may be able to use a solid state block. Sounds like a neat solution.

The digital interface side should be easy, its not too hard to amplify a CMOS output so it switches a decent Voltage/Current. using something like a BJT or Mosfet in Common emitter mode should get the job done. There are heaps of circuit diagrams on the web for driving relays from TTL Levels using this method.

hope this helps.
oddbudman

Solid State relays, can do the Job for you.

I also suggest the relay solution, you can wire the relay to switch on when u have to off the device, ie. make the device switch from the Normally Connected (N/C) terminal so that when the relay is off the device is on and when the relay is switched on the device switches off. This would decrease the ON time for the relay and increase its life.