GE Masoneilan SVI II ESD Installation And Maintenance Manual page 59

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 ESD. 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 Classification for the area.
Remote piping of the actuator venting is possible to reduce the amount of natural gas
released into the area around the SVI II ESD. 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 ESD. Consider the bleeding and releasing of natural gas when evaluating the
Hazardous Clarification for the area.
Refer to "Installing an SVI II ESD in a Natural Gas Environment" on page 165 for installation
instructions.
© 2016 General Electric Company. All rights reserved.
Area classification is the responsibility of the end user.
NOTE
Do not remove the instrument cover or connect to an electrical
WARNING
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.
EXPLOSION HAZARD - DO NOT DISCONNECT EQUIPMENT OR
WARNING
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 ESD. Even after disconnecting the SVI II
ESD from all the pneumatic connections Natural Gas may still be
present within the SVI II ESD.
EXPLOSION HAZARD - NATURAL GAS MAY EXCAPE FROM THE SVI
WARNING
II ESD UPON REMOVAL OF ANY COVER OR COMPONENT. Ensure
the cover is correctly installed before putting this unit into service.
EXPLOSION HAZARD - AN IMPROPERY INSTALLED COVER COULD
WARNING
LEAK NATURAL GAS INTO THE AREA. The interior of the SVI II ESD
is positively pressure with supply medium. Appropriate safety
measures must be taken to handle pressurized natural gas that
may enter the electrical conduit or cable system.
Masoneilan SVI II ESD Installation and Maintenance Manual
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