controlling 3x230V AC motor - relay does not respect delay times

Other Hardware Motors, Mechanics, Power and CNC
1

hello, i need to control a 3x230V AC motor
i switch it on using a ''arduino 5V relay'' board which activates a 12V DC coil of a big relay.

Even without placing the motor on this ''big'' relay, the Arduino switches on the relay, which activates the coil, remains on for the requested delay. When this delay i over i digitalwrite the relaypin so it is switched off, meaning the coil of the big relay must no longer be activated....
again a delay off time is requested, but here it often, but not always goes wrong....
Often the relay is switched off=> coil is of and almost immediately the relay is been reactivated, without respecting the delay Off time..... it seems almost like the arduino gets a reset when powering down the 5V relay / coil.....
i use a separate power supply for the arduino
a second 5 V DCpower supply is used to power the 5V relay.
a other 12V DC power supply is used to activate de relay coil, which eventually will power the 1.5kW 3x230V motor...

any suggestions?
thanks
Carl
Carl

2

The problem is in the code you didn't post.

3

Or in the hardware you didn't post.

Is the coil of the "big relay" powered by 230volt AC.
If so, did you use a snubber network across the 230volt coil (or the Arduino relay contacts).
Ahh, missed that the big relay coil is 12volt.
Then you need a diode across that coil, as outsider said.
Leo..