Configuration and Use Manual 133
Troubleshooting
Measurement Performance TroubleshootingCustody TransferCompensation Measurement Performance TroubleshootingCustody TransferCompensation Measurement Performance TroubleshootingCustody TransferCompensation Measurement Performance TroubleshootingCustody TransferCompensation
Constant mA output Non-zero HART address (multi-drop
communications) (primary mA output
only)
Set HART address to zero. See Section 12.19.
Output is fixed in a test mode Exit output from test mode. See Section 5.3.
Burst mode enabled (primary mA
output only)
Disable burst mode.
Zero calibration failure Cycle power.
Stop flow and rezero. See Section 5.5.
mA output consistently out of
range
Fault condition if fault indicator is set to
upscale or downscale
Check the fault indicator settings to verify
whether or not the transmitter is in a fault
condition.
If a fault condition is present, see Section 12.7.
LRV and URV not set correctly Check the LRV and URV. See Section 12.21.
Consistently incorrect mA
measurement
Output not trimmed correctly Trim the output. See Section 5.4.
Incorrect flow measurement unit
configured
Verify flow measurement unit configuration. See
Section 12.20.
Incorrect process variable configured Verify process variable assigned to mA output.
LRV and URV not set correctly Check the LRV and URV. See Section 12.21.
mA reading correct at low
currents but wrong at higher
currents
mA loop resistance may be too high Verify mA output 1 or mA output 2 load
resistance is below maximum supported load
(see installation manual for your transmitter).
Consistently incorrect
frequency measurement
Output not scaled correctly Check frequency output scale and method. See
Section 12.22. Verify voltage and resistance
match the frequency output load resistance
value chart (see your transmitter installation
manual).
Incorrect flow measurement unit
configured
Verify flow measurement unit configuration. See
Section 12.20.
Erratic frequency
measurement
RF (radio frequency) interference from
environment
See Section 12.14.4.
Cannot zero with Zero
button (Model 1500/2500
transmitters only)
Not pressing Zero button for sufficient
interval
Button must be depressed for 0.5 seconds to be
recognized. Depress button until LED starts to
flash yellow, then release button.
Core processor in fault mode Correct core processor faults and retry.
Cannot connect to terminals
33 & 34 in service port mode
(Model 1500/2500
transmitters only)
Terminals not in service port mode Terminals are accessible in service port mode
ONLY for a 10-second interval after power-up.
Cycle power and connect during this interval.
Leads reversed Switch leads and try again.
Transmitter installed on multidrop
network
All Model 2500 devices on network default to
address=111 during 10-second service port
interval. Disconnect or power down other
devices, or use RS-485 communications.
Cannot establish Modbus
communication on terminals
33 & 34 (Model 1500/2500
transmitters only)
Incorrect Modbus configuration After 10-second interval on power-up, the
transmitter switches to Modbus
communications. Default settings are:
• Address=1
• Baud rate=9600
• Parity=odd
Verify configuration. Default settings can be
changed using ProLink II v2.0 or higher.
Leads reversed Switch leads and try again.
Table 12-2 I/O problems and remedies continued
Symptom Possible cause Possible remedy