EMS 24V Power Supply Troubleshooting

Identify Power Path

1. Determine complete incoming power path to the power supply.
2. Typical configuration:

Verify Incoming Power

1. Using a multimeter confirm voltage is present at the line side of the fuse block
2. If no voltage is present, upstream supply or breaker is the issue
3. Verify Fuse Operation
   • Measure voltage at the load side of each fuse
   • Confirm continuity of each fuse if necessary
   • Ensure correct fuse rating:
     • Required: 2A fuse
     • Over 2A does not provide adequate protection and must be replaced

Verify Switch/Disconnect Operation

1. For enclosures equipped with an external switch (older units):
   • Confirm voltage at the input and output terminals of the switch.
   • Verify proper operation (no voltage drop across a closed switch).
2. For newer enclosures:
   • Note: No external switch present; skip this step and proceed downstream.

Documentation for Replacement Power Supply

In the event the issue is determined to be isolated to the 24V power supply, please provide the following information.

1. Details of troubleshooting performed and results.
2. Clear photos of the power supply including the model number