Baker Hughes Masoneilan SVI II AP, Quick Start Manual

Page: 38 / 108

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Connecting the Tubing and Air Supply
The last step in hardware installation for the SVI II AP is to connect the air supply to the positioner.
This section describes the process for connecting the tubing and air supply to a single and dou-
ble acting positioner.
Natural Gas Supply Considerations
If the pneumatic system is connected to natural gas, the pneumatic control system constantly
bleeds a small amount of the natural gas into the area around the SVI II AP. Also, during a vent
cycle (actuator pressure relief), natural gas from the actuator is released into the area around
the SVI vent port. Consider both sources of natural gas when evaluating the Hazardous Classifi-
cation for the area (See GEA19681 Masoneilan Valves SVI II AP Installation and Maintenance
Manual for further discussion on installing an SVI II AP in a natural gas environment).
Remote piping of the actuator venting is possible to reduce the amount of natural gas released
into the area around the SVI II AP (See GEA19681 Masoneilan Valves SVI II AP Installation and
Maintenance Manual for further discussion on installing an SVI II AP in a natural gas environ-
ment). Installing remote actuator vent gas piping does not capture all gas emitted. A small
amount of natural gas still bleeds constantly in the area around the SVI II AP. Consider the bleed-
ing and releasing of natural gas when evaluating the Hazardous Clarification for the area.
NOTE Area classification is the responsibility of the end user.
The interior of the SVI II AP is positively pressurized with supply medium. Appropriate safety mea-
sures must be taken to handle pressurized natural gas that may enter the electrical conduit or
cable system.
WARNING
Do not remove the instrument cover or connect to an electrical
circuit unless the power is disconnected. Natural gas will escape
into the surrounding atmosphere upon disconnecting any of the
pneumatic connections or removing any cover or pressure
containing component.
WARNING
EXPLOSION HAZARD - Do not disconnect equipment or remove
cover unless power has been de-energized or the area is know to
be non-hazardous.
Natural gas may be contained within the SVI II AP. Even after
disconnecting the SVI II AP from all the pneumatic connections
Natural Gas may still be present within the SVI II AP.