Use and Care Manual

Not for

Reproduction

Electronic Governor

The engine electronic governor system allows for improved

control and increased generator performance compared

to mechanically governed systems. The result is smooth

steady-state operation without the “hunting” common to

some mechanical governors. The system also reduces

speed variations under engine loading and unloading and

significantly reduces frequency fluctuation experienced when

the engine is under higher loads.

The electronic governor system is composed of a stepper

motor (B), stepper motor throttle control linkages (C), and

throttle side linkages (A). The control board contains a digital

controller that processes engine speed information and sends

appropriate commands to the stepper motor to control the

position of the engine throttle.

Since the electronic governing system controls the engine

throttle demand based upon generator load, the following

service codes and/or conditions may be related to an

electronic governing system issue:

• Engine Does Not Start

• Over Speed

• Under Frequency

• Unstable No Load Engine Control

While trouble shooting any of these conditions, a verification

of the electronic governor system can be initiated through the

control panel – advanced menu options – Electronic Governor

Check. Refer to the Installation Manual for Advanced Menu

Operation.

Electronic Governing Check:

The generator has an electronic governing check feature that

will turn on the stepper motor and move the throttle linkage

clockwise and counterclockwise within the throttle limits. The

test will rotate the stepper motor and move the throttle arm

between the wide open throttle and dead idle limits 4 times

with a 2 second delay between each throttle sweep. This will

allow visual verification that the stepper motor is functioning

properly and the control linkages are connected. The engine

will not attempt to start during this test. If the stepper motor

does not move, or if a linkage binds, then service may be

required.

NOTICE If stepper motor does not move, please make sure

the stepper motor connector is attached.