Emerson NZ Series Instruction Manual page 8

NZ/NZ-M and NZOS/NZOS-M Series
All Installations
An NZ/NZ-M or NZOS/NZOS-M Series regulator bleeds no gas to atmosphere during normal operation, making it suitable
for installation in pits and other enclosed locations without elaborate venting systems. This regulator also can be installed in
pits subject to flooding by venting the pilot spring case above the expected flood level so that the pilot diaphragm is always
exposed to atmospheric pressure.
1. Only personnel qualified through training and experience should install, operate and maintain a regulator. Before
installation, make sure that there is no damage to or debris in the regulator. Also, make sure that all tubing and piping are
clean and unobstructed.
Eye nuts are installed to aid in the handling and installation of the Regulator Assembly only. Do not attempt to lift more
weight than the regulator with these eye nuts.
2. Install the regulator so that the flow arrow on the main valve matches the flow direction of process fluid through the
regulator. The NZ/NZ-M and NZOS/NZOS-M Series normally be installed in a horizontal pipeline with the actuator above
the body, for other position, please contact your local sales office.
3. Use gaskets between pipeline and regulator flanges when installing a regulator with flanged end connections.
A regulator may vent some gas to the atmosphere in case of malfunction. In hazardous or flammable gas service,
vented gas may accumulate, causing personal injury, death or property damage due to fire or explosion. Install vent
line from the regulator pilot to a remote, safe location away from air intakes or any hazardous location. The end of the
vent line or stack opening must be pointed down and protected against condensation or clogging.
4. JP Series pilots have a 1/8 NPT vent connection in the spring case. The pilot vent opening should be pointed down. Protect
the vent opening from condensation or clogging. To remotely vent gas from the spring case, connect piping or tubing to
the spring case connection. The piping or tubing should vent to a safe location, have as few elbows as possible and have a
screened vent that points down on its exhaust. Install the regulator and any remote vent piping or tubing so that the vent
is pointed down and protected from condensation, freezing or substances that may clog it.
To avoid freeze-up because of pressure drop and moisture in the gas, use anti-freeze practices, such as heating the
supply gas or adding a de-icing agent to the supply gas.
5. The JP Series pilot connections are 1/4 NPT. Connect a downstream sense line from the "B" port on the JP Series pilot to a
straight run of pipe at least 5 pipe diameters from the regulator outlet as shown in Figures 1 and 2, using 8 mm or larger
outside diameter tubing. If such a distance is not practical, connect the control line away from elbows, swages, nipples or
any area where abnormal flow velocities occur.
6. Connection a downstream sense line from the upper casing of main valve to a straight run of pipe at least 5 pipe
diameters from the regulator outlet as shown in Figures 1 and 2, using 10 mm or large outside diameter tubing (for NZ
and NZOS Series 1", outside diameter of tubing must be at least 14 mm, and inside diameter not less than 11 mm). If such
a distance is not practical, connect the control line away from elbows, swages, nipples or any area where abnormal flow
velocities occur.
Note: The optimal location for the sense lines is between the regulator and the downstream block valve. To prevent damage
to the regulator during startup, the sense lines of pilot and main valve should be located on the same side of the downstream
block valve.
7. Install hand valves in the downstream sense and bleed lines if desired. If hand valves are installed, they should be full flow
valves, such as a full port ball valve.
Wide-Open Monitor Regulator
1. Follow the procedures in the All Installations section and then continue with step 2 of this section. The sense lines of both
the upstream and downstream pilots will be connected to the downstream piping (see Figures 3 and 4).
2. Connect the pilot supply line "S" port for the downstream regulator to the upstream pipe.
Working Monitor Regulator
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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CAUTION
WARNING
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CAUTION
CAUTION