Relay Removal And Replacement - Emerson Fisher 546NS Instruction Manual

546NS Transducer
June 2021
WARNING
For explosion proof applications, disconnect power before opening the transducer cover. Personal injury or property
damage may result from fire or explosion if power is not disconnected.
CAUTION
The presence of Emerson Automation Solutions personnel and also approval agency personnel may be required if you
service (other than normal, routine maintenance, such as calibration) or replace components on a transducer that carries a
third‐party approval. When you replace components, use only components specified by the factory. Substitution with
other components may void the third‐party approval. Also, always use proper component replacement techniques, as
presented in this manual. Improper techniques can cause poor quality repairs and impair the safety features of the device.
Figure 8 shows the torque motor and associated parts. Shaded key numbers indicate parts that should not be
disassembled from the torque motor because the magnetism in the torque motor magnets will decrease
permanently.
Certain troubleshooting and alignment procedures are described at the end of this section. These may serve as a guide
to correct some problems. Improper supply pressure and mechanical defects in pneumatic and electrical connections
should be apparent upon inspection and repaired as appropriate.
CAUTION
Never disassemble the torque motor assembly because the magnetism in the torque motor magnets will decrease
permanently. Shaded key numbers indicate parts that should not be disassembled from the torque motor (see figure 8). If
troubleshooting or alignment attempts indicate either a faulty torque motor or the necessity of disassembling the torque
motor consult your Emerson sales

Relay Removal and Replacement

Use the following procedure when removing and replacing a relay assembly. Refer to figure 9 for key number
locations, unless otherwise directed.
1. Loosen the two mounting screws (key 68), and remove the relay assembly from the transducer case (key 1,
figure 7).
2. To install the replacement relay assembly, install the two relay mounting screws (key 68) into the relay assembly.
Apply lubricant (key 96) to the O‐rings, and make sure the O‐rings (keys 72, 73, and 74) are in place on the relay
assembly.
3. Install the relay assembly on the transducer case. Tighten the mounting screws.
4. With the torque motor installed, apply supply pressure to the transducer case, and check the relay assembly for
leaks with a soap solution.
CAUTION
Never disassemble the relay as this could result in permanent drift issues.
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office.
Instruction Manual
D103425X012