ABB 266 MODBUS User Manual

6 Troubleshooting
266 MODBUS® multivariable transmitter User manual 2105216 Rev. AB | 71
5. Once the recommended action has been taken, access the diagnostics menu again to determine if the alarm has cleared.
If the alarm has not cleared, and multiple actions were recommended, move to the next action and complete it. When the
alarm clears, it is not necessary to continue. If additional alarms are present, repeat steps 4 through 6 for each alarm,
repeating until all alarms are cleared.
Table 16: Diagnostic code cause and action
Diagnostic code
Possible Cause
Recommended action
P-dP Sensor Fail
— Mechanical damage on the measuring cell.
— Measuring cell loses filling fluid, diaphragm is
torn, sensor damaged.
The measuring cell is not field replaceable. Replace the
266 MODBUS
®
multivariable transmitter.
Static Pressure Sensor
Fail
Error in the current circuit for scanning the static
pressure.
The measuring cell is not field replaceable. Replace the
266 MODBUS
®
multivariable transmitter.
Sensor Temperature Fail
Error in the current circuit for scanning the
temperature.
The measuring cell is not field replaceable. Replace the
266 MODBUS
®
multivariable transmitter.
Process Temperature
Sensor Fail
A/D converter error of the temperature sensor.
Replace the transmitter's electronics module (go to
section 5.6, Replacing the electronics module).
— Incorrect wiring
— Wire break
— Process conditions exceed critical limit
— Process conditions have changed, causing
the device to have operated out of the design
limits
— Verify that the RTD is properly wired to the
transmitter (go to section 3.6.4, Transmitter
wiring). Rewire if necessary.
— Verify that the process temperature has not
reached a critical limit, causing the RTD to fail.
Use the MODBUS
®
registers to view the RTD
maximum ever measured value and the RTD
minimum ever measured value. If the RTD has
exceeded a critical limit, replace the RTD (go to
section 5.9, Replacing the RTD probe).
P-dP Out Of Limits
The transmitter's measuring range or model
configuration is not appropriate for this application.
Verify that the measuring range was calculated
correctly and that the transmitter is the correct model for
the current application conditions. If incorrect:
— Replace the transmitter with the correct model
configuration.
— The incorrect model may still operate correctly,
just not for this application or measurement
range.
Static Pressure Out of
Limits
The static pressure of the process exceeds the limits
of the measuring cell.
Verify that the measuring range was calculated
correctly and that the transmitter is the correct model for
the current application conditions. If incorrect:
— Replace the transmitter with the correct model
configuration.
The incorrect model may still operate correctly, just not
for this application or measurement range.
A wrong transmitter model may have been selected.
An overshoot of the static pressure can reduce
accuracy, mechanically damage the membrane, and
make a calibration or replacement necessary.
Use the MODBUS
®
registers to view the SP maximum
ever measured value and the SP minimum ever
measured value. If an overshoot of the SP has
occurred, the unit is damaged. Replace the 266
MODBUS
®
multivariable transmitter.
Sensor Temperature Out
of Limits
The temperature of the process environment
influences the pressure transmitter. Excess
temperatures can reduce accuracy, impair device
components, and make a calibration or replacement
necessary.
The 266 MODBUS
®
multivariable transmitter requires
replacement. Verify that the replacement transmitter is
suitable for the process conditions. A different type of
installation could be necessary, e.g. use of diaphragm
seals.

ABB 266 MODBUS Specifications

General

Brand	ABB
Model	266 MODBUS
Category	Transmitter
Language	English