Specifications

Installation 00-02-0175 page 4 of 6
Direct Installation into the Wall of the
Pressure Vessel
1. Determine that the float travel is not
obstructed by the coupling in
the vessel wall, internal
baffles, etc.
Do NOT use more than
one arm extension P/N
15050395.
2. BE SURE that the float
and extension are tight
and that the lock washer is
in place.
3. Before installing the level
switch a suitable pipe thread sealant
is recommended. Screw the unit directly into the threaded
connection in the wall of the pressure vessel.
4. Be sure that the electrical connection is positioned at the
bottom. For L1200N the 1/8 NPT pneumatic connection
should be on top (the 1/4 NPT vent connection should be on
the bottom). See “Pneumatic models” section for further
instructions for the L1200N.
5. Make the electrical wiring connections according to
appropriate wiring diagrams for the alarm or shutdown
system to be used. The electrical connection is 1/2-14 NPT.
Electrical wiring and conduit should be installed by qualified
personnel according to the NEC.
6. BE SURE all electrical connections are insulated and the
cover is fully installed before reconnecting electrical power.
7. BE SURE all pressure connections are tight before
pressurizing the system.
Installation with a Weld
Collar
1. The weld collar, P/N
15050375, must be welded
into the wall of the
pressure vessel according
to code standards and
good welding practices.
2. Follow above instructions
for installation directly into
the wall of the pressure
vessel.
3. NOTE: Weld collar 15050375 can
be used ONLY with model L1200. It cannot be used with
L1200N.
Installation Using External
Float Chamber 15051098
1. Install the float chamber 15051098 on the outside wall of the
pressure vessel using 1 NPT piping. Position the 2 NPT
threaded connection at the height where you want the level
switch to operate. The 2 NPT threaded connection must be
positioned away from the tank wall.
2. A tee is typically installed at the bottom of the lower 1 inch
pipe riser to allow draining of the float
chamber for servicing or replacement.
NOTE: A typical installation
with Blocking and Bleed valves is
shown at right.
3. Install the L1200 or
L1200N
in the 2 NPT connection
of
the float chamber.
BE SURE float travel
is not restricted and that the
float is tight onto
the float shaft.
4. To complete installation and
wiring, follow the instructions for
mounting directly into wall of the vessel and for wiring.
Pneumatic Models
1. All pneumatic models
operate on the vent
principle. The
pneumatic signal
source MUST BE
CLEAN AND DRY.
The input pneumatic
signal must be
regulated between 30
and 70 psi (207-483
kPa) [2.07-4.83 bar].
If produced gas is used as the
signal source, it should be taken
after gas passes through the final scrubber.
A suitable filter must be positioned before the L1200NDVO
to prevent liquids and/or particulates from entering the dump
valve operator.
NOTE: Check filter periodically for wear and tear and
elements that hamper the flow of the pneumatic signal.
2. All pressure connections must be tight and maintained tight
so as not to leak air/gas.
3. Valve seat adjustment can be made if air/gas begins to leak.
Care should be taken when adjusting as only slight movement
is necessary to stop the leakage; excessive force will bind the
PRESSURE VESSEL INSTALLATION: L1100, L1200, and L1200N
Hex Socket Set Screw
• loosen for adjustment
• tighten after adjustment
Hex Adjustment Nut
• turn left until air
seepage stops
• Caution: only slight
adjustment is needed—too
much will lock up mechanism
Trip Cam (float down)
• should be in
this position
• non-adjustable
New Dump Valve
Operator Assembly
p/n 15010216
L1200N
MURPHYGAGE
®
Filter/Regulator
Pneumatic
Signal
Tank
Tank Wall
Weld Collar
L1200
Explosion proof
conduit seal
where required.
Tank
Wall
Level
Switch
Explosion proof
conduit seal
where required.
Tan k
Float
Chamber
Block
Valves
Level
Switch
Tee
Bleed
Valve
Explosion proof
conduit seal
where required.
L1200N
CAUTION: USE “NON SPARKING TOOLING”.
DISCONTINUED