Instruction Manual
D200124X012
2500 and 2503 Controllers/Transmitters
June 2017
6
WARNING
Personal injury or property damage may result from fire or explosion if natural gas is used as the supply medium and
preventive measures are not taken. Preventive measures may include, but are not limited to, one or more of the following:
Remote venting of the unit, re‐evaluating the hazardous area classification, ensuring adequate ventilation, and the
removal of any ignition sources. For information on remote venting of this controller refer to page 13.
Sensor Assembly
Table 2 lists sensors recommended for use with controller/transmitters. Table 4 contains displacer and torque tube
materials. For sensor installation and maintenance, refer to the appropriate sensor instruction manual.
WARNING
When replacing the sensor assembly, the displacer may retain process fluid or pressure. Personal injury or property
damage may occur due to sudden release of the pressure. Contact with hazardous fluid, fire, or explosion can be caused by
puncturing, heating, or repairing a displacer retaining process pressure or fluid. This danger may not be readily apparent
when disassembling the sensor assembly or removing the displacer. Before disassembling the sensor or removing the
displacer, observe the more specific warning provided in the sensor instruction manual.
Uncrating
Unless ordered separately, the controller/transmitter is attached to the sensor when shipped. Carefully uncrate the
assembly.
CAUTION
Sensors used for interface or density control may be so large and heavy that the torque tube cannot fully support their
weight in air. On the 249VS, a travel stop is used to prevent damage. Do not remove this travel stop assembly without first
removing the displacer from the displacer rod. Refer to the appropriate instruction manual for 249 cageless sensors.
Note
Caged sensors have rods and blocks installed at each end of the displacers to protect the displacers in shipping. Remove these
parts before you install the sensor to allow the displacer to function properly.
Caged sensors come with the displacer installed in the cage. If a tubular gauge glass is ordered with the sensor, the
gauge glass is crated separately and must be installed at the site. A damping plate is installed in the lower screwed or
flanged connection (see figure 3) to provide more stable operation. Be certain that the cage equalizing connections
and the damping plate are not plugged by foreign material.
