Troubleshooting a Low Voltage condition at the device. (Contactor, Coil, Relay, Brake etc.)
Example low voltage electrical condition in circuit Problem- Voltage from A1 to A2 of contactor coil =15vdc, should be 24vdc (assume 24vdc solenoid coil is the load)
Check at power supply from +24 to 0vdc is it 24VAC?
Yes
Go to next step (Power supply good)
No
Power down
Remove all wires connected to +24, 0vdc on power supply
Power up
Recheck power at power supply. If 24vdc, then power supply is most likely OK unless the power supply has weekend over time. Otherwise there is an excessive amount of current drawing down power supply or something wrong with power coming into the primary side.
Problem could be a loose connection or bad contact in a device/relay/ or contactor.
Follow through the series circuit and tighten all wire terminals. Don't forget to check A2 (0VAC) wire terminals too.
If machine tool is relatively new also check for terminals crimped on insulation of wire
If still have problem. Check entire circuit with meter and test each point on each side of every contact, circuit board, relay or any other device in the series circuit. Looking for the voltage drop across the device and then troubleshooting that device. See points in example circuit that were checked
Contactor relay troubleshooting - see electrical shorts for other possible solutions
GENERAL DISCLAIMER:
All data on this website is provided without charge or obligation by myself or anyone else who contributes to this site. It is the responsibility of the reader to perform any action outlined here in a safe and responsible manner. The reader assumes all responsibility for service or actions taken as a result of the information contained here. We assume no responsibility for personal or property damage, any type of monetary losses or losses caused directly or indirectly from the material provided in this Web page or any pages contained within the Website. If this site has been translated into another language, we are also not liable for how the site content has been translated. Click here for full disclaimer and terms