AMOT 10GEF, Operation And Maintenance Manual, Page: 43 / 80

43
Electric Actuator
OMMG00012 Rev 12 – NOV 2019
4.7 Tighten the grubscrew (10).
4.8 Repeat from step 4.1 without loosening the cam grubscrew to check
that the first switch operates when the manual handle is turned two
complete turns (after take-up of backlash).
4.9 Check that the second switch on the same cam (Aux close limit
switch ‘ACLS’) operates after a further counter-clockwise ½ turn of
the manual handle.
Note
It is not possible to adjust the ACLS separately from the CLS.
5 Remove any electrical continuity circuits connected to the terminal strip.
6 Ensure that the actuator cover O ring is correctly fitted and undamaged.
7 Refit the actuator cover and secure with the socket head cap screws.
CAUTION
Adjustment of the limit switches affects the calibration of the optional
Positioning Electronics Unit. If fitted, it must be re-calibrated before
the actuator is brought into service (refer to OMM47962X00013).
8 If fitted, calibrate the positioning electronics unit (refer to the Positioning
Electronics Unit Manual).
9 Energise the actuator power supply and control circuits and check for
correct operation.
4.8.5 Limit Switch Adjustment – Rotor Visible
The limit switches and mechanical end stops are set by the manufacturer and
should not need adjustment unless the cams or switches are replaced or
disturbed. During manufacture, the limit switches are set up relative to the
valve fully open and closed positions. The mechanical end stops are then set in
position, a further two complete turns of the manual operating handle.
This procedure assumes that observation of the valve rotor is not possible
(installed in pipework) and sets the limit switches relative to the factory set
mechanical end stop positions.
Adjust the limit switches as follows (refer to Fig 13, page 40):
WARNING
Lethal voltages are exposed when the actuator cover is removed,
presenting an electric shock hazard to personnel. Electrical power
supplies must be isolated from the actuator before the cover is
removed.
1 Switch off and isolate the actuator electrical power supply.
2 Remove the socket head cap screws and carefully lift off the cover.
Note
The cams are adjusted until the limit switches operate (indicated by an
audible click). In conditions of high noise levels, an electrical continuity