Section 3: Jackscrew Override; Jackscrew Operating Instructions; Actuator Stroke Adjustment; Models 006 Through 270 - Emerson Biffi Morin Series Installation, Operation And Maintenance Manual

Installation, Operation and Maintenance Manual
MAN-03-04-103-0738-EN Rev. 1

Section 3: Jackscrew Override

The jackscrew option is intended for infrequent or emergency on-site operation of the
automated valve.
3.1

Jackscrew Operating Instructions

1.
2.
3.2

Actuator Stroke Adjustment

The jackscrew has a built-in actuator stroke adjustment, see Figure 3 and 4.
3.3

Models 006 through 270

See Figure 3:
1.
2.
3.
Figure 3
Jackscrew Override
Disengage power supply and vent air from actuator.
Operate the handwheel to drive the actuator into the desired position. Valve
position can be verified by checking the actuator position indicator. For models
006 through 270, the jackscrew must be returned to the fully retracted position
before actuator can resume normal operation. Back the jackscrew out until it
stops. Air will leak from the jackscrew unless it has been fully retracted against
its internal seal.
Retract the jackscrew override completely by rotating counter clockwise.
Loosen the lock nut and turn the brass adjusting screw to the desired position.
The handwheel will rotate with the adjusting screw. Never make stroke
adjustments by turning the handwheel only.
Tighten lock nut.
Jackscrew Override - Models 006 through 270
JACKSCREW FULLY RETRACTED
Stroke adjusting screw
Jackscrew
Lock nut
Seal
JACKSCREW EXTENDED
Section 3: Jackscrew Override
May 2020
Actuator stroke
adjusting screw
Note: Air escapes unless
jackscrew is fully retracted
Jackscrew seal
3