IMPULSE® •Series 5 AC Variable Frequency Drives: EF Fault | CMCO

This SOP provides a step-by-step guide to troubleshoot the EF fault in IMPULSE®️ VG+ Series 5 drives. The EF fault is generated when the drive sees both directional commands at the same time.

2. Procedure

2.1 Understand the EF Fault
Understand that the EF fault indicates a forward/reverse run command input error This means that the drive is seeing both directional commands at the same time

2.2 Identify the Inputs for the Directional Commands
The inputs for the directional commands are on the interface card that the control wiring is connected up to. In a standard factory default setting, the inputs would be terminals S1 and S2

2.3 Monitor the Input Terminal Status
Go to the monitor mode display and look at U01-10 input terminal status. When you give the drive a run command with a single directional command, the two digits on the far right change state from a 0 to a 1 and then the drive immediately shows EF, indicating that it’s seeing both inputs at the same time.

2.4 Identify the Cause of the Fault
One of the causes of this fault could be just a single strand of wire from either the wiring input on S1 or S2 touching the other input S1 or S2. This will be enough to generate the fault.

2.5 Inspect the Drive
Take the cover off the drive and look at the interface card. It’s not visible in this video, but there might be just a single strand of wire touching from S1 to S2.

3. Conclusion
This SOP provides a comprehensive guide to troubleshoot the EF fault in IMPULSE®️ VG+ Series 5 drives. Always ensure to follow the steps in order to prevent any mishaps or further complications

Access more CMCO training from our Magnetek team here - https://motion.cmco.com/l/963023/2023...

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