Adjustments To The Ballhead Governor; Before Start-Up - Woodward PGA-EG 200 Product Manual

Manual 54065

Adjustments to the Ballhead Governor

Use the optional "Mode Select Valve" (see Figure 2) to set to the "PG Mode"
position to start the engine under control of the ballhead governor.
The valve can be set to "PG Mode" by appropriate electric, pneumatic, or manual
means:

Electrical—Can be either energize (24 Vdc, 0.87 A) or de-energize to set
PG Mode. See specification sheet for your application.

Pneumatic—60 to 75 psi (414 to 517 kPa) sets PG Mode.

Manual—Set knob to PG Mode.
If the Mode Select option is not included on the governor, the PG-EG can be put
under ballhead operation by running the electrical side to maximum, either
through the electrical governor control, or by simulating a maximum signal at the
electrical connection. (Most PG-EGs are "reverse acting" and an absence of any
electrical control signal will place the ballhead in control.)
1. Set the compensation needle valve to 1/8 turn open from the fully closed
(clockwise) position.
2. Assure the ballhead speed setting is at the idle condition (manual speed set
to idle, pneumatic speed signal at minimum speed).
To Adjust the Compensation Needle Valve after Start up:
1. With the prime mover operating at IDLE speed, open the compensation
needle valve until the governor begins to hunt. Let the governor hunt for
several minutes to remove trapped air in the hydraulic circuits. DO NOT
allow a level of hunting which would cause damage to the prime mover.
2. Close the compensation needle valve slowly until hunting just stops. Do not
close the needle valve completely. To prevent slow governor response,
keep the needle valve open as far as possible. The needle valve setting can
be from 1/16 to 2 turns open.
3. Check the stability of the governor output by disturbing the governor speed
setting. The compensation adjustment is satisfactory when the governor
returns to speed with only a small overshoot or undershoot. Once the
needle valve adjustment is correct, it is not necessary to change the setting
unless there is a change in oil viscosity. Additional adjustment may be
necessary if stability problems exist at full speed-full load conditions
Woodward
PGA-EG, PGG-EG, PGM-EG Installation

Before Start-up

It maybe necessary to upset the governor speed momentarily to
cause the governor to hunt. (A rapid fluctuation in the speed setting
of the PG-EG will usually accomplish this upset.)
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