Sierra INNOVA-MASS 240-VT, Instruction Manual

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Chapter 5 Troubleshooting & Repair Sierra 240/241 Series Instruction Manual
5-12 IM-240
Figure 5-3.Vortex Sensor Connector
With the sensor still disconnected, go to the first level of the
hidden diagnostics and display the vortex shedding frequency,
f. Hold a finger on the three exposed pins on the analog board.
The meter should read electrical noise, 60 Hz for example. If
all readings are correct, re-install vortex sensor wires.
4. Verify all meter configuration and troubleshooting steps
previously described. There are many possible causes of this
problem, consult factory if necessary.
Symptom: Meter Displays Temperature Fault
1. For remote mounted electronics, carefully check all the wiring
connections in the remote mount junction box. There are 18
connections that must be correct, verify each color (black and
red), shield, and wire number.
2.
Go to the first level of the hidden diagnostics and check the
resistance of the rtd1. It should be about 1080 ohms at room
temperature.
3. Using ESD precautions and hazardous area precautions,
remove the electronics enclosure window cover. Disconnect
the temperature sensor from the electronics stack or the remote
feed through board. Refer to Figure 5-1 or 5-2. Measure the
resistance across the outside pins of the temperature sensor
connector. It should read approximately 1080 ohms at room
temperature (higher resistance at higher temperatures).
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