Fisher EZH User Manual

Europe, Middle East and Africa Document Only
Types EZH and EZHSO
16
3. Introduce upstream pressure by slowly opening
inlet valve.
4. Slowly open valve R2.
5. Open valve R3.
6. Close valve R4, the regulator Type EZHSO close.
7. Open valve R4.
8. Close valve R3.
9. Slowly open downstream valve, making sure that
there is a constant sufcient pressure drop across the
regulator. If downstream pressure climbs too close to
upstream pressure, the regulator will again fully open.
In this case, start-up procedure needs to be repeated.
For a single regulator, set the pilot to the desired
outlet (control) pressure according to the Pilot
Adjustment procedure.
For a wide-open downstream monitor installation,
adjust the upstream working pilot until intermediate
pressure is higher than the desired setpoint of the
monitor pilot. Adjust the downstream monitoring pilot to
the desired monitoring takeover pressure. Reduce the
upstream pilot to the normal outlet pressure setting.
For a wide-open upstream monitor installation, adjust
the downstream working pilot to a setpoint higher than
the setpoint of the monitor pilot. Adjust the upstream
monitoring pilot to the desired monitoring takeover
pressure. Reduce the downstream pilot to the normal
outlet pressure setting.
For a working monitor installation, adjust the setpoint
of the upstream monitor pilot to the desired maximum
pressure. Adjust the upstream working pilot to the desired
intermediate pressure setting. Adjust the downstream
pilot to a pressure setting slightly above the upstream
monitor pilot pressure setting. Adjust the upstream
monitor pilot to its desired setpoint. Establish nal desired
downstream pressure by adjusting the downstream
working regulator pilot.
10. After adjusting the Type PRX pilot(s) to the desired
pressure setting(s), slowly open the downstream
block valve wide open.
11. Close the bypass valve, if used.
Type OS2 Manometric Box Set Point
Verication Procedure
Using the vent valve supply a pressure equal to the set
pressure foreseen for the regulator.
- 1
st
release relay stage
à Set (Stage 1)
- Slam-shut valve plug
à Open (Stages 2 and 3)
à Progressively increase the pressure until
tripping occurs
à Adjust setting if necessary (D103683X012). Note
the set point value on the equipment or mark it on a
commissioning document
STAGES 2 AND 3
TRIGGERED
POSITION
STAGE 1
R121
Figure 15. Setpoint Verication Phase
Type PRX Pilot Adjustment
To adjust a standard Type PRX pilot, loosen the
locknut and turn the adjusting screw.
Turning the adjusting screw clockwise into the
spring case increases the spring compression and
pressure setting. Turning the adjusting screw counter
clockwise decreases the spring compression and
pressure setting.
When the required pressure setting is maintained
for several minutes, tighten the locknut to lock the
adjusting screw in position.
Type PRX Pilot Restrictor and Damper
Screw Adjustment
Note
Recommended initial setting of the
restrictor screw is turned completely in
(clockwise) and then turned out 1/2 turn.
The damper screw initial setting is turned
completely out (counter clockwise).
The Type PRX/125 (upstream monitor pilot
in working monitor installations) does not
have a restrictor screw.
The restrictor screw of the Type PRX pilot can be used if
there is hunting of the set pressure. Slowly turning out the
restrictor screw (counterclockwise) will help steady the
set pressure.
Turning out the restrictor screw will slightly decrease set
pressure, so adjustment of the pilot adjusting screw may
be necessary.
The damper screw can be turned in (clockwise) to
slow the response of the regulator. It is advisable that
adjustment of the damper and restrictor screws be
limited to 1/4 turn at a time to observe the response of
the regulator(s).

Fisher EZH Specifications

General

Brand	Fisher
Model	EZH
Category	Controller
Language	English