Norad
Electrical
- Mar 17, 2009
- 7
Hello-
I'm using an SCR motor controller for a brushed DC motor 0-90VDC.
The input power voltage to the SCR is 240VAC and it is rated for both 50/60Hz. The control voltage is 0-10VDC from a PLC.
I've tested it at 60Hz, and it seems to work fine.
At 50Hz, a branch breaker to the SCR blows.
After blowing the breaker several times, the SCR faults_forever and needs to be replaced.
This has happened twice.
I am not sure that the frequency is the problem, or if there is some other issue. Can the frequency make a difference with SCR controls?
Another thought is that the SCR controller has acceleration/decceleration potentiometers on it. I may have these set incorrectly, allowing the control voltage to get to the motor before the motor is ready to accept. I had been using these potentiometers for ramping rate.
I have multiple motor speeds programmed in, that jump up and down rpms quickly.
I can't tell if the motor blows the breaker during start or during ramp.
Any thoughts at all are welcome!
Norad
I'm using an SCR motor controller for a brushed DC motor 0-90VDC.
The input power voltage to the SCR is 240VAC and it is rated for both 50/60Hz. The control voltage is 0-10VDC from a PLC.
I've tested it at 60Hz, and it seems to work fine.
At 50Hz, a branch breaker to the SCR blows.
After blowing the breaker several times, the SCR faults_forever and needs to be replaced.
This has happened twice.
I am not sure that the frequency is the problem, or if there is some other issue. Can the frequency make a difference with SCR controls?
Another thought is that the SCR controller has acceleration/decceleration potentiometers on it. I may have these set incorrectly, allowing the control voltage to get to the motor before the motor is ready to accept. I had been using these potentiometers for ramping rate.
I have multiple motor speeds programmed in, that jump up and down rpms quickly.
I can't tell if the motor blows the breaker during start or during ramp.
Any thoughts at all are welcome!
Norad