Bernard ASP Series Motorized Actuator

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Fault Log · Field Report

Bernard ASP Series Motorized Actuator — No Response Local or Remote

Plant: Cement  |  System: Bernard ASP series motorized actuator  |  Downtime: Actuator down until card replacement

Symptom

A Bernard ASP series motorized actuator stopped responding completely — no movement from local control at the actuator, and no movement from CCR setpoint commands either. Both control paths dead at the same time pointed away from a simple selector or wiring issue and toward something common to both paths.

Investigation

Worked through the actuator systematically, ruling out one subsystem at a time:

  • Power supply — checked all three phases at the incoming supply. All healthy.
  • Local/remote selector — checked the magnetic switch contacts on the selector. All making good contact.
  • Mechanical binding — turned the actuator by handwheel to rule out a jammed or seized valve/gearbox. Moved freely, not mechanically stuck.
  • Limit switches — checked open limit, close limit, and torque limit switches. All operating correctly.
  • Motor thermal protection — checked the thermal sensor contact. Found closed and healthy, so no thermal trip was blocking the start.
  • Termination — went through every terminal connection on the actuator. No loose or degraded terminations found.

With power, selector, mechanics, limit switches, thermal protection, and wiring all confirmed good, everything pointed to the main electronic control card as the remaining suspect.

Root Cause

Faulty main electronic card inside the actuator. With every field-level input and mechanical path confirmed healthy, the card was the only element left in the control chain that could explain a total loss of response on both local and remote command — it sits between all those inputs and the motor contactors, so a card fault takes both paths down together.

Fix

Replaced the main electronic card. Actuator responded normally to both local and CCR commands afterward.

Lesson

When an actuator loses both local and remote control at once, don't waste time chasing the selector switch or a single input — a fault that kills both paths simultaneously is almost always something common to both, like the main control card. The value here is in the elimination sequence: power, selector contacts, mechanical freedom, limit switches, thermal protection, and terminations all checked out clean before the card was condemned. Confirming every field-level component first means the card replacement is a confident call, not a guess.

Run into a similar Bernard ASP card failure? Drop a comment — always useful to compare failure patterns across units.

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