Loss of VIA Analog Signal
Schneider Electric · Altivar 212 Variable Speed Drive
What does E-18 mean?
This fault is triggered when the analog input signal at the VIA terminal drops below the detection level configured by parameter F633 and persists for 300 milliseconds or longer. It indicates a problem with the external analog signal source, its wiring, or the drive's input circuit. Loss of a critical control signal can lead to incorrect motor operation, uncontrolled speed, or system shutdown, posing a risk of process disruption, equipment damage, or safety hazards.
Additional Steps
Steps 1–2 are listed in Priority Fix.
- 3
Check the setting of parameter F633 (Loss of VIA Analog Signal). Ensure the detection level is appropriate for the expected minimum signal from your analog source. If loss of signal detection is not required, set F633 to 0 to disable this fault.
- 4
Ensure the signal source's output impedance and type (voltage/current) are compatible with the drive's input requirements for the VIA terminal to prevent signal degradation or incorrect readings.