12 | GE Oil & Gas
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Standby Monitor
NOTE: This procedure is based on the 1st Regulator
being the operating regulator and the 2nd regulator
being the monitor regulator.
1. Set operating pilot (#1) spring at the MAXIMUM
setting.
2. Set monitor pilot (#2) spring to the MINIMUM (zero)
setting.
3. Purge station and open outlet regulator or vent to
allow flow through the station
4. Slowly open inlet block regulator. Full inlet pressure
should be present at the Monitor Regulator and the
Monitor Regulator should be closed.
5. Increase the pilot spring setting of the Monitor
Regulator until the desired monitor override setting is
reached. Lock in pilot setting.
6. With some flow going through the station, begin to
lower the operating pilot setting of the Operating
Regulator until the desired outlet pressure is
achieved.
NOTE: When the set point of the Operating Regulator
becomes less than the set point of the Monitor
regulator, the interstage pressure will drop from
approximately full inlet pressure to 5-10 psi (0.35 -
0.68 bar) above the outlet pressure at low flow rates.
Checking Standby Monitor Operation
1. With flow going through the station, slowly increase
the setting of the Operating Regulator. When
the pressure reaches the setpoint of the Monitor
Regulator, the monitor should take control and the
interstage pressure should increase to almost full
inlet pressure.
2. Reduce the setting of the Operating Regulator
back to the required outlet pressure. The interstage
pressure should drop to 5-10 psi (0.35 - 0.68 bar)
above the outlet pressure as the Operating Regulator
takes control.
NOTE: When the differential across the entire station
(P1-P2) is less than 60 psig (4.13 bar) then alternate
outlet piping as shown below, is recommended for
added station
capacity. This applies to the Series 20
Pilot only; consult with GE for applicability to other
manufacturer’s pilots.
Figure 9 - Standby Monitor Schematic