Set-value encoder at 4mA...20mA defective

What does Sd5 mean?

This fault indicates a problem with a 4-20mA current loop signal used as a set-value input, likely from an encoder or other process sensor. This could be due to an open circuit, short circuit, or the signal source being faulty. By default, this critical condition triggers a full TRIP, inhibiting all ignition pulses and resetting the Ready signal, as a lost or incorrect set-value can lead to uncontrolled operation. Manual reset is required.

• Open circuit in the 4-20mA current loop wiring between the sensor/encoder and the drive's input (e.g., X7).
• Short circuit to ground or power supply within the 4-20mA loop, drawing excessive current.
• External 4-20mA sensor/encoder failure, producing no output or a fixed out-of-range value (e.g., 0mA or 22mA).
• Incorrect scaling or configuration of the 4-20mA input on the drive (e.g., P6-01 for input type, P6-02 for scaling minimum).
• Insufficient external power supply for the 4-20mA sensor, if it's a 2-wire passive transmitter.

Click steps to track your progress.

1. 1

   Disconnect the 4-20mA signal wires at the drive's input terminals (e.g., X7).

2. 2

   Measure the current directly from the 4-20mA sensor using a multimeter in series, observing for a stable 4-20mA range.

3. 3

   Check the total resistance of the 4-20mA loop wiring; ensure it is below the maximum allowed by the sensor's power supply.

4. 4

   Verify the drive's input parameter settings (e.g., P6-01 for Analog Input 1 Mode, P6-02 for Analog Input 1 Minimum Value) are correctly configured for 4-20mA.

5. 5

   Confirm the external power supply for the 4-20mA sensor is providing stable voltage (e.g., 24VDC).