Emerson Rosemount 2090P Reference Manual page 62

Rosemount 2088 and 2090
Table 5-1. Rosemount 2088/2090Troubleshooting for 4-20 mA output.
Symptom
Transmitter milliamp reading is zero
Transmitter Not Communicating with
Field Communicator
Transmitter milliamp reading is low or high
Transmitter will not respond to changes in
applied pressure
Digital Pressure Variable reading is low or high
Digital Pressure Variable reading is erratic
Milliamp reading is erratic
5-2
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Corrective Actions
Verify power is applied to signal terminals
Check power wires for reversed polarity
Verify terminal voltage is 10.5 to 42.4 Vdc
Check for open diode across test terminal
Verify the output is between 4 and 20 mA or saturation levels
Verify terminal voltage is 10.5 to 42.4 Vdc
Verify clean DC Power to transmitter (Max AC noise 0.2 volts peak to peak)
Check loop resistance, 250  minimum (PS voltage -transmitter voltage/loop current)
Have Field Communicator poll for all addresses
Verify applied pressure
Verify 4 and 20 mA range points
Verify output is not in alarm condition
Verify if 4 – 20 mA output trim is required
Check test equipment
Check impulse piping or manifold for blockage
Verify the transmitter is not in multidrop mode
Verify applied pressure is between the 4 and 20 mA set points
Verify output is not in alarm condition
Verify transmitter is not in Loop Test mode
Check test equipment (verify accuracy)
Check impulse piping for blockage or low fill in wet leg
Verify transmitter is calibrated properly
Verify pressure calculations for application
Check application for faulty equipment in pressure line
Verify transmitter is not reacting directly to equipment turning on/off
Verify damping is set properly for application
Verify power source to transmitter has adequate voltage and current
Check for external electrical interference
Verify transmitter is properly grounded
Verify shield for twisted pair is only grounded at one end
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Industry Automation
Reference Manual
00809-0100-4690, Rev FC
June 2011
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