Look at the physical LEDs on the PLC output card. If the logic output LED for the motor starter is illuminated but the physical magnetic starter coil does not engage, check the wiring between the terminal block and the starter coil. If the LED is dark, connect a laptop to the PLC using its programming software to check which input condition (such as a missing sensor signal or timer block delay) is blocking the rung from achieving continuity.
Here are some fixes and solutions to common problems that may arise when working with electrical motor controls:
) while the motor runs. Compare this to the Full Load Amps (FLA) on the motor nameplate. Look at the physical LEDs on the PLC output card
Use advanced electrical tests to narrow down the problem to a specific wire, contactor, or coil. Step 4: Fix and Repair the Defect
Isolate all energy sources. Lock the disconnect switch. Tag it with your name and date. Here are some fixes and solutions to common
Understand the difference between NO and NC contacts in logic. 12-15: Starters, AC/DC Motors
Regular maintenance prevents the majority of integrated system control failures. Action Required Target Value Check for pitting/wear Clean, unpitted surfaces Connections Torque terminal screws Semi-Annually Manufacturer spec (in-lbs) Overload Relays Verify trip settings Matches motor nameplate FLA VFD Heatsink Blow out dust/debris Visual cleanliness Insulation Megohmmeter test > 100 Megohms Step 4: Fix and Repair the Defect Isolate
Finding a "fix" for issues related to the usually refers to one of two things: resolving technical errors in an industrial motor control system or finding solutions to problems within the textbook or workbook itself.
Use a multimeter to trace voltage through the stop button, start button, and coil. Common "Fixes" in Motor Controls
Reset the VFD to factory defaults and re-enter the motor nameplate data (FLA, Voltage, RPM, Frequency).