Analog Input Low Fault

What does 50 mean?

One or more analog input signals are below 50% of their minimum signal range. This suggests a defective or loose control cable, or a malfunction in the signal source itself. This can lead to incorrect control inputs and affect drive operation.

• Broken or loose wiring connection at the drive's analog input terminals (e.g., AI1+, AI1-, AGND).
• Sensor malfunction or failure causing its output signal to drop below 50% of the minimum configured range (e.g., 4-20mA sensor outputting <2mA, 0-10V sensor outputting <0.5V).
• Incorrect scaling parameters for the analog input (e.g., P3.3.1.2 for AI1 min value, P3.3.1.3 for AI1 max value) not matching the sensor's output range.
• Excessive electrical noise or ground loop interference corrupting the low-level analog signal, causing it to fall below the valid threshold.
• Misconfiguration of the analog input supervision fault threshold (e.g., P3.3.1.4 for AI1 supervision fault threshold).

Click steps to track your progress.

1. 1

   1. Check the physical wiring connections at the drive's analog input terminals (e.g., AI1, AI2) for looseness, corrosion, or damage.

2. 2

   2. Using a multimeter, measure the voltage or current directly at the sensor's output terminals to confirm the actual signal value.

3. 3

   3. Verify the analog input parameters (e.g., P3.3.1.1 for AI1 type, P3.3.1.2 for AI1 min value, P3.3.1.4 for AI1 supervision fault threshold) match the connected sensor's specifications.

4. 4

   4. Trace the analog input cable for damage or breaks, checking continuity from the sensor to the drive's input terminals.

5. 5

   5. Temporarily connect a known good signal source (e.g., potentiometer, signal generator) to the drive's analog input to test the drive's input circuit functionality.