How to Slow down a DC motor in Ladder logic

[lekan]

I kind write a PLC code (ladder logic) for ramping up or ramping down a Motor, how can i write a code to detect the motor when its slowing down.....Any help in this matter will be appreciated

[support]

You probably need some kind of tachometer that send pulses to the PLC's Pulse Measurement inputs and measure the speed using the PULSEFREQUENCY function.

[philipjoseph]

Check if the Frequency Drive controling the DC motor has MODBUS RTU comunication. If so, depending of the VFD, you may be able to read the frequency from the drive, that will let you know if the Motor slows down.

Philip