Emerson Micro Motion 2500, Руководство по конфигурации и использованию

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Enhanced core processor LED states
(continued)
Table 12-9:
LED state Description Recommended action
Core processor internal failure The meter requires factory service.
12.32 Perform a 700 core processor resistance test
Note
You can perform a resistance test only on a 700 core processor.
Procedure
1. Power down the transmitter.
2. Remove the core processor lid.
3. At the core processor, disconnect the 4-wire cable between the core processor and
the transmitter.
4. Measure the resistance between core processor terminal pairs 3–4, 2–3, and 2–4.
Terminal pair Function Expected resistance
3–4 RS-485/A and RS-485/B 40 k
Ω
to 50 k
Ω
2–3 VDC– and RS-485/A 20 k Ω to 25 k Ω
2–4 VDC– and RS-485/B 20 k Ω to 25 k Ω
5. If any resistance measurements are lower than specified, the core processor may
not be able to communicate with a transmitter or a remote host. The meter may
need factory service.
Postrequisites
To return to normal operation:
1.
Reconnect the 4-wire cable between the core processor and the transmitter.
2. Replace the core processor lid.
3. Restore power to the transmitter.
Note
When reassembling the meter components, be sure to grease all O-rings.
Troubleshooting
196 Micro Motion Model 2500 Transmitters with Configurable Input/Outputs