CAUTION
To prevent damage to the pilot during
Startup, the sense and bleed lines should be
located on the same side of the downstream
block valve.
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EZHSO Series installation, a vent valve downstream of
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in the PRX Series pilot bleed line connection (line from
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YHQWOLQHLVSUHIHUUHGWRSURYLGHVXI¿FLHQWÀRZ
For optional remote pneumatic loading of a
PRX Series pilot, make the spring case piping
connections just as they would be made for remote
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Wide-Open Monitor Regulator
CAUTION
The working regulator must be rated for
the maximum allowable operating pressure
of the system because this will be its inlet
pressure if the monitoring regulator fails.
Also, the outlet pressure rating of the
monitoring pilot and any other components
that are exposed to the intermediate pressure
must be rated for full inlet pressure.
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bleed control lines of both the upstream and downstream
pilots will be connected to the downstream piping (see
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Connect the pilot supply line for the downstream
regulator to the outlet “R” port of the Type SA/2 pilot
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Working Monitor Regulator
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WKHQFRQWLQXHZLWKVWHSRIWKLVVHFWLRQ7KHVHQVH
line of the upstream monitor pilot (from Port A on the
Type PRX/125) and the bleed (Port S) and sense lines
(Port A) of the downstream pilot will be connected to the
GRZQVWUHDPSLSLQJVHH)LJXUH
Connect an inlet supply line from the upstream piping
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VXSSO\¿OWHUUHJXODWRU
Connect a control (sense) line from the “A” port of
the upstream working Type PRX/120 pilot to the
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PPRUODUJHURXWVLGHGLDPHWHUWXELQJ
Connect a downstream bleed line from the “S” port
of the upstream working Type PRX/120 pilot to the
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PPRUODUJHURXWVLGHGLDPHWHUWXELQJ
Figure 6. Working Monitoring System Operational Schematics
(B
TYPE PRX
S - BLEED PORT
B - SUPPLY PORT
L - LOADING PORT
A - SENSING PORT
TYPE SA/2:
V - SENSING PORT
R - PILOT SUPPLY PORT
M - INLET PORT
V
R
M
S
S
B
B
L
L
A
A
TYPE SA/2
TYPE PRX/120
TYPE PRX/125
V
R
M
S
B
L
A
TYPE SA/2
TYPE PRX/120
TYPE EZH
TYPE EZH
CHECK
VALVE
CHECK
VALVE
INLET PRESSURE
OUTLET PRESSURE
ATMOSPHERIC PRESSURE
INTERMEDIATE PRESSURE
PILOT SUPPLY PRESSURE
LOADING PRESSURE
8
EZH and EZHSO Series
