Figure 14.
Controller in Closed (Tripped) Position
Figure 13.
Controller in Open (Reset) Position
27
- CLOSE THE UPSTrEaM VaLVE
- CLOSE THE DOWnSTrEaM VaLVE
High-Pressure Shutoff
Low-Pressure Shutoff
Supply pressure through outlet purge valve.
Open the purge valve.
Check the value of the shut-off pressure and for any downstream leakage.
Check the value of the shut-off pressure and for any downstream leakage.
Adjust the setpoint, if necessary.
Adjust the setpoint, if necessary.
Table 6.
Flow Chart for Checking Shut-off Mechanism
Systematic Maintenance is recommended as Specified Below:
Overpressure Shutoff (OPSO) Setpoint
adjustment Only (Figures 4 and 15)
• Using a flathead screwdriver or 1/4 in. drive socket, turn
the OPSO adjusting screw (key 43) clockwise until it
stops turning.
•
Apply nominal outlet pressure of the associated
regulator to the downstream system.
•
Reset the controller per the resetting procedure,
(Refer to the Resetting Procedure section for detailed
resetting instructions).
•
Slowly increase the downstream pressure to the desired
OPSO value (P
dso
).
• Using a flathead screwdriver or 1/4 in. drive socket, turn
the OPSO adjusting screw counterclockwise (key 43)
until the controller trips.
Manual Shut-off Procedure (Figure 9)
Using a screwdriver, press the manual shut-off button
(key 23) to manually trip the controller.
Manual reset Procedure (Figures 10 to 13)
for VSX4 and VSX8 Series
CaUTiOn
Equipment installed downstream of
the
controller can be damaged if the following
procedure for resetting the controller is
not followed. This equipment includes the
integral controller/regulator configurations.
note
an OPSO spring must be present and
adjusted before proper reset can be
achieved. if OPSO adjustment has not yet
been made, a FULL adjustment can be used.
note
Test lockup of the regulator and replace the
regulator valve plug/disks as needed.
Step 1:
•
Slowly pull the reset button (key 30) away from the
controller. This slow movement allows for a slow bleed
of the pressure across the controller’s disk and seat
area. The operator should be able to hear the pressure
bleeding through the system.
Step 2:
•
When the pressure has equalized and the air bleeding
sound has dissipated, the reset button (key 30) can be
pulled completely away from the controller by hand until
the internal shut-off mechanism has been re-latched.
Step 3:
•
Once the operator feels the click of the re-latch occurring,
the reset button (key 30) should be pushed completely
back into its original position.
Trip indicator (Figures 13 and 14)
The trip indicator (key 27) provides a visual indication
as to whether the controller is opened (latched/reset) or
closed (tripped).
VSX4 and VSX8 Series
11
