Description
3.3 Operation with natural gas
SIPART PS2 with PROFIBUS communication
Operating Instructions, 09/2007, A5E00127926-07
21
3.3
Operation with natural gas
3.3.1
Safety notes for operation with natural gas
When operating the positioner with natural gas, you must follow and adhere to the following
safety notes:
WARNING
Operation with natural gas
1.
Only the "EEx ia" version of the positioner and optional modules with the "EEx ia" type
of protection may be operated with natural gas. Positioners with other types of
protection, e.g. flameproof enclosure or versions for zones 2 and 22 are not permitted.
2.
Do not operate the positioner with natural gas in closed spaces.
3.
Natural gas is continuously blown off in the servo-drive depending on the model. Special
care must therefore be taken during maintenance activities near the positioner. Always
ensure that the immediate surroundings of the positioner are adequately ventilated.
4.
The mechanical limit switch module may not be used when operating the positioner with
natural gas.
5.
Depressurize the devices operated with natural gas adequately during maintenance
activities. Open the cover in an explosion-free atmosphere and depressurize the device
for at least two minutes.
3.3.2
Natural gas as an actuator medium
Introduction
Normally, you operate the positioner with compressed air. Natural gas has been approved as
an actuator medium for intrinsically safe positioners with the "EEx ia" type of protection.
Note
Quality of natural gas
Only use natural gas which is clean, dry and free from additives.
Functional principle
The positioner releases the used natural gas through the exhaust air outlet E. The exhaust
air outlet E is equipped with an attenuator.
As an alternative to this standard configuration, the exhaust air outlet can be replaced with a
G¼ screwed fitting. You have to dismantle the attenuator for this purpose.
