Emerson VSSG, VSG manual Operation, Fail Position

Section 4 • Operation

Fail Position

The temperature control valve remains in the last posi- tion when power is removed.

Screen Display

The oil temperature control valve, identified as “OIL MIX” on the main PLC display screen, shows a numerical value with “%” as units. This is to be understood as “% OPEN.” It is a direct indication of the position of the ball valve.

100% OPEN

Oil flow stream is entirely bypassing the oil cooler.

99% to 1% OPEN

Oil flow stream is partially bypassing the oil cooler and partially diverted to the oil cooler.

0% OPEN

Oil flow stream is entirely diverted to the oil cooler.

Handwheel

Actuator

MANUAL OVERRIDE

The actuator of the oil temperature control valve has a handwheel that can be engaged to override the electri- cally determined position of the ball valve.

1.Push handwheel down and rotate to engage inter- nal slot with flats, see Figure 4-6.

NOTE

Actuator does not have mechanical stops. Do Not rotate past open or close position. Use visual indicator to position actuator.

2.Once engaged, push down handwheel a second time to disengage gear train and rotate CLOCKWISE to OPEN or COUNTER CLOCKWISE to CLOSE.

3.To return actuator to normal operation, first check “% OPEN” on control panel. If value is 100%, return actuator to OPEN position as shown on the visual indicator. If value is 0%, return actuator to CLOSE position as shown on the visual indicator.

Visual Indicator

Figure 4-6. Oil Temperature Control Valve (Oil Mixing Valve)

4 – 8 VSG/VSSG • Installation, Operation and Maintenance Manual •Vilter/Emerson • 35391SSG