K6002

I just finished a temperature controller project with the velleman kit.
I have used the K6002 and K6001 in combination with other components, e.g. contactors to turn on/off 600 Watt water pumps.

I intended to let the controller turn on and off one of these contactors, but I never got that far.

Another contactor is used to turn on/off the installation.
The K6002 and K6001 always stay on.

Every time I start/stop the installation, and this installation on/off contactor switches, the temp. controller shows random stuff on the display and hangs. I have to turn on and off the power supply to the controller to restart it.

It seems that the controller does not like the effects of switching contactors?
It seems to influence the power supply to the K6002 controller causing this behaviour?

Does anyone have an idea on how I can fix this?

Kind regards,

Peter

This is a problem that will not be easy to solve. First, you will need to determine if the rubbish that causes the problem enters via the power supply transformer or via the relay contacts. Removing all wires from the relay contacts can give you an indication. For best results, switch a low DC current with the on-board relays, which in turn controls a larger power relay to switch the AC load. If necessary, add suppressors to the AC power relay contacts (e.g. VDR). Keep AC wiring as far as possible from the electronics. Some experimenting will be necessary.

Since the error even occurs while not using the controller (controller relay’s are not switching, it is just indicating temperature), I assume that this rubbish is comming from the supply.
I will test this this evening.

Is there a way to keep the power supply from the transformer to the controller “clean”?

Peter

As suggested I tested the controller while all the relay contacts were disconnected and exactly the same thing happened.

So the rubbish is coming through the power supply.

So I need to get it “clean”.

I’ve read on many articles on the net that RC suppressors could help me to solve the problem?

How do I need to do this? Any other suggestions are welcome.

Peter

Did you suppress the contacts of the water pump contactor with e.g. VDR ?

I intend to suppress the contacts of the contactors with rc suppressors tomorrow.
I’ll report on the results as soon as I have them.

Well, IT WORKS!

I applied RC suppressors on the coils of the contactors and now the controller works great.

Thanks for the advice!

Peter