Startup And Adjustment - Fisher EZH Instruction Manual

6. For Type EZHSO installation, a vent valve
downstream of the regulator is needed. It should
be installed directly in the Type PRX pilot bleed line
connection (line from port "S" to pipe). A full bore
NPS 1/4 ball valve for the vent line is preferred to
provide sufficient flow.
Wide-Open Monitor Regulator
1. Follow the procedures in the All Installations
section and then continue with step 2 of this
section. The sense and bleed control lines of
both the upstream and downstream pilots will
be connected to the downstream piping (see
Figure 13).
2. Connect the pilot supply line for the downstream
regulator to the outlet "R" port of the Type SA/2
pilot supply filter regulator.
Working Monitor Regulator
1. Follow the procedure in the All Installations section
and then continue with step 2 of this section. The
sense line of the upstream monitor pilot and the
bleed and sense lines of the downstream pilot
will be connected to the downstream piping (see
Figure 14).
2. Connect an inlet supply line from the upstream
piping to the inlet "M" port of the downstream
Type SA/2 pilot supply filter regulator.
3. Connect a control (sense) line from the "A" port of the
upstream working Type PRX pilot to the intermediate
pressure portion of piping, using 8/10 (inside
diameter) tube.
4. Connect a downstream bleed line from the "S"
port of the upstream working Type PRX pilot to the
intermediate pressure portion of piping, using 8/10
(inside diameter) tube.

Startup and adjustment

Pre-startup Considerations
Each regulator is factory-set for the outlet pressure
specified on the order. If no setting was specified,
outlet pressure was factory-set at the mid-range of
the pilot control spring. Before beginning the start-
up procedure in this section make sure the following
conditions are in effect:
• Block valves isolate the regulator
• Vent vales are closed
• A bypass, if any, is in operation.
In all cases, check the control spring setting to make
sure it is correct for the application.
Types EZH and EZHSO
CauTiOn
Be sure to slowly introduce pressure
into the system to prevent downstream
overpressure due to potential rapid
pressure increase. Pressure gauges
should always be used to monitor
downstream pressure during startup.
Procedures used in putting this
regulator into operation must be
planned accordingly if the downstream
system is pressurized by another
regulator or by a manual bypass.
Type EZH OS2 Slam-shut version
In the case of opening the mechanism box lid:
1. after arming, never leave the key on
the stem
2. Never put your fingers in or near the
reset mechanism area
When using a Type Sa/2 pilot supply
filter regulator, the differential pressure
across the regulator must be at
least 3 bar for optimum regulator
performance. The Type Sa/2 can be
removed if differential pressure across
the regulator is less than 3 bar and inlet
pressure stays at or below 13.8 bar.
Startup
Type EZH Startup:
1. Make sure all block valves, vent valves and control
line valve(s) are closed.
2. Back out the pilot adjusting screw(s).
3. Slowly open the valves in the following order:
- Inlet block valves.
- Pilot supply and control line valve(s), if used.
4. Crack open the outlet block valve or bypass valve
to allow minimum flow.
5. After adjusting the Type PRX pilot(s) to the desired
pressure setting(s), slowly open the downstream
block valve wide open.
6. Close the bypass valve, if used.
Type EZHSO Startup:
1. Make sure all block valves, except valve R4, vent
valves and control line valve(s) are closed.
2. Back out the pilot adjusting screw(s).
note
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