ABB AV1, Operating Instructions Manual

Page: 53 / 126

INTRODUCTION
5 - 1
SECTION 5 - OPERATING PROCEDURES
INTRODUCTION
This section details the equalizing valve of the optional manifold
(Type AV___1___ positioner).
NOTE: This section only applies when the positioner is equipped
with a manifold assembly.
EQUALIZING AND AIR SUPPLY SHUTOFF VALVE
The equalizing valve, supplied with the manifold assembly, allows
the actuator to be manually or automatically operated. By turning
the valve handle to MAN, supply pressure to the positioner is cut
off and the 01 and 02 ports are tied together, allowing manual
repositioning of the actuator.
NOTE: It is important to understand that the equalizing valve is
not a bypass valve. Be aware that if the actuator is not secured
before transferring the valve handle of the manifold, the actuator
will move.
Transfer from Automatic to Manual Operation
1. Manually lock the actuator or final control element.
2. If equipped with a manifold and equalizing valve, push in the
valve handle and turn it to the
MAN position.
3. If not equipped with a manifold and equalizing valve, turn off
the supply air.
NOTE: If there are no means of locking the actuator or final con-
trol element, it will move in the direction of the process or
mechanical load when the supply air is turned off.
Transfer from Manual to Automatic Operation
1. Verify that the valve handle is in the MAN position.
WARNING
Lock the actuator in place or be aware of the possible move-
ment before moving the equalizing valve to MAN or AUTO.
Failure to do so could result in injury to personnel.