DKG-255 User Manual Firmware V-1.0
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Engine overspeeds:
1) With the unit powered-up, if the actuator opens fully:
a) Disconnect wiring at terminals E and F.
If the actuator closes then the speed signal is faulty, probably due to electrical noises.
Check shielding and wiring.
If the actuator is still open, then disconnect the terminal B. If the actuator is still open,
then the actuator is feeded by an external connection or short circuit. If the actuator
shuts-off then the unit is damaged.
Speed unstable:
1) Readjust GAIN and STABILITY as desribed in chapter 8.
2) Check the speed sensor for:
a) Signal strength
b) Wiring
c) Shielding
3) Check the actuator-fuel lever system for loose mechanical linkage, or friction:
a) Make the checks while the engine is operating.
4) Check for electromagnetic disturbance sources in close proximity as:
a) battery chargers
b) ignition systems
c) radio transmitters.
Make a test by turning them off mometarily. If the stability cannot be reached, then enclose
the unit in a separate and grounded metal sheet cabinet.
Systems in very harsh electromagnetic conditions as found in close proximity of powerful
transmission systems may require shielding on all cables and even special EMI shielding.
5) Check the engine fuel and injection system:
Faulty injectors, blocked filters etc… may prevent the governor controller to maintain a
constant speed.
Do not crank again.
