The servo strains and stops or trips the overcurrent protection — what should I do?
The GS740-3P has overcurrent and mechanical stall protection; the current limit is set at approximately 7A at the factory and can be configured in the 3.5A-10A range. If the protection is tripping, first check cable friction, sheath fixing and free movement of the throttle lever. Raising the limit does not solve the mechanical problem, it only hides it.
Typical sources of strain:
- A cable sheath with sharp bends or crushed
- A throttle lever joint seizing because of rust and soot
- The cable bottoming out at the end of the mechanical stroke; the upper limit may have been taught incorrectly
- The servo bracket being misaligned, the cable entering the sheath at an angle
What to do: Stop the engine, disconnect the cable at the clamp and move the throttle lever by hand; if the lever is stiff the problem is not on the kit side. Then, with the cable disconnected, drive the actuator; if it moves freely the load is coming from the cable. Correct the route, use the guides, fix the sheath at both ends. Then clear the memory and teach the upper limit again.
The system also has an independent watchdog, working with a timeout of approximately 2 seconds. These protection layers are there to protect the actuator and the wiring; they are not an engine overspeed protection or an emergency stop function.
Full topic: Electronic speed and throttle control on diesel engines