Mounting Cageless Sensor; Side-Mounted Sensor - Emerson Fisher 2503 Instruction Manual

2500 and 2503 Controllers/Transmitters
June 2017
On fluid or interface level applications, position the sensor so that the center line on the cage (see figure 6) is as close
as possible to the center of the fluid level or interface level range being measured. Also consider installing a gauge
glass on the vessel, or on the sensor cage (if the cage is tapped for a gauge).

Mounting Cageless Sensor

Note
If a stillwell is used, install it plumb so that the displacer does not touch the wall of the stillwell. If the displacer touches the wall,
the unit will transmit an erroneous output signal.
Since the displacer hangs inside the vessel, provide a stillwell around the displacer if the fluid is in a state of continuous
agitation to avoid excessive turbulence around the displacer.
Note
Displacers used in an interface level application must be completely submerged during operation. If displacers aren't completely
submerged, they will not calibrate or perform properly. To obtain the desired controller or transmitter sensitivity may require
using either a thin‐wall torque tube, an oversized displacer, or both.
Note
If the controller/transmitter is not mounted on the sensor, refer to the Installing Controller/Transmitter on Sensor procedures in
the Maintenance section. This section also provides instructions for adding a heat insulator to a unit.
Attach a cageless sensor to a flanged connection on the vessel as shown in figure 7. For interface or fluid level
applications, install a gauge glass on the vessel.
Side‐Mounted Sensor
If a stillwell is required (see figure 7), attach the displacer to the displacer rod from inside the vessel.
Connect the displacer as shown in figure 8, locking the assembly with the cotter spring provided. If a stillwell is not
required, attach the displacer rod before mounting the sensor on the vessel. Then, you can swing the displacer out
horizontally for insertion into the vessel. However, once the sensor is installed and the displacer drops to a vertical
position, the displacer may not be capable of being withdrawn for servicing later. Be sure there is another access to the
displacer to permit swinging it to a horizontal position or to permit disconnecting it from the displacer rod.
If an extension is used between the displacer spud and the displacer stem end piece, make sure the nuts are tight at
each end of the displacer stem extension. Install and tighten suitable bolting or cap screws in the flanged connection
to complete the installation.
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Instruction Manual
D200124X012