Woodward UG-10 Dial, Инструкция по установке и эксплуатации

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Manual 03040 UG Dial Governor
Woodward 25
22. Install the governor cover and dial plate.
Test Completion
For operation of units running alone, set droop at zero. Reducing droop to zero
allows the unit to change load without changing speed (zero droop operation is
also called isochronous operation).
On units connected in parallel or to a single shaft, set the least amount of droop
possible to provide satisfactory load division. Droop allows load division between
two or more prime movers that drive the same shaft or are paralleled in an
electrical system.
For ac generating units tied in with other units, set droop sufficiently high
(reference number 30 to 50 or more on the dial) to prevent interchange of load
between units.
If one unit in the system has enough generating capacity, set its governor on
zero droop, and it will regulate the frequency of the prime mover system. If its
capacity is not exceeded, this unit will handle all load changes.
Operate the SYNCHRONIZER knob of the governor with zero droop to adjust the
system’s frequency. Operate the SYNCHRONIZER knobs of the governors that
have speed droop to distribute load between units.
When two units are set up for optimum single unit performance, paralleling
problems can be encountered. For example, governor response can be too fast
on one governor, requiring too high a speed droop setting to prevent a constant
load interchange between the two governors. When this occurs, the
compensation setting should be moved towards maximum, reducing the single
unit transient performance capability but allowing stable parallel operation within
the allowable speed droop range. Also, check the amount of output shaft travel
on each governor. Too little output shaft travel on a governor can require too high
a droop setting on that governor to obtain steady state control.
Compensation must be properly adjusted to the particular engine
and load to provide stable operation (see Compensation
Adjustments).
When UG governors are used on generator sets operating in parallel and the
lead unit is shifted to slave and vice versa, zero droop must be set on the lead
unit to maintain the frequency for which it is set, and droop must be set on the
slave unit for load distribution between the two units.
For more information on load sharing, please refer to manual 25195,
Governing
Fundamentals .