Emerson Rosemount 2120, Справочное руководство

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4. Plug in the replacement cassette, secure it with the two screws.
5. Reconnect the wiring.
6. Set the mode switch to “Wet On” with a one second delay, ready for calibration (see
Figure 6-6 ).
Figure 6-6: Mode Switch Setting (Replacement Cassette)
7. Reconnect the power supplies to the Rosemount 2120.
6.7.2 Calibrate the replacement cassette
Prerequisites
Some of the calibration sequence steps are time-dependent and must be carried out
within the noted times. The purpose of the time dependency and switching sequence is to
prevent an accidental calibration from occurring.
Verify:
• The sensor forks are clean and dry.
• The mode switch is set to “Wet On” with the time delay set to one second.
Procedure
1. Verify the 'heartbeat' LED is flashing at a rate of one flash per second.
Proceed to Step 5 if it is on continuously.
2. Apply a magnet to the test-point.
After a one second delay, the LED will be lit continuously.
3. Within one second, rotate the mode switch two steps clockwise.
The LED will go out within two seconds.
4. Within three seconds, rotate the mode switch two steps counter-clockwise.
Proceed to Step 8 .
After a two second delay, the LED should start flashing twice per second.
5. Apply a magnet to the test-point.
After a one second delay, the LED will flash once every second.
6. Within one second, rotate the mode switch two positions clockwise.
The LED will go out within two seconds.
7. Within three seconds, rotate the mode switch two steps counter-clockwise.
After a two second delay, the LED should start flashing twice per second.
Service and troubleshooting Reference Manual
March 2022 00809-0100-4030
62 Reference Manual