HART Communications
105
Instruction Manual
Section 10: haRT Communication
LIQ-MAN-1066
April 2017
1066ph/ORp Status Bits
Byte / Bit
Meaning/Class
Device Status Bits Set
0 / 1
Reference Impedance Too high / Error
The reference impedance is above the high fault
setpoint. The reference electrode may be coated or plugged.
1. Clean or replace the sensor.
2. Check sensor wiring.
3. Increase the setpoint value.
4. Set the reference impedance level to high.
4 – More Status available
7 – Field Device Malfunction
0 / 2
Glass Impedance Too high / Error
The glass impedance is above the high fault setpoint. The glass electrode may be
severely coated.
1. Clean or replace sensor.
2. Check sensor wiring.
3. Increase the glass impedance high fault setpoint.
4 – More Status available
7 – Field Device Malfunction
0 / 3
Broken ph Glass / Error
The glass impedance is too low. The glass electrode of the pH sensor may be
cracked.
1. Check sensor. Replace sensor if cracks are present.
2. Check sensor wiring.
3. Check preamplifier location configuration.
4 – More Status available
7 – Field Device Malfunction
2 / 3
ph voltage Too high / Warning
The sensor voltage is outside the expected range for a pH measurement.
1. Check sensor wiring.
2. Replace sensor.
4 – More Status available
4 / 0
ph Slope Too high / Warning
The pH slope calculated during buffer calibration exceeded the maximum slope
limit.
1. Check the buffers used and retry buffer calibration.
2. Increase the maximum slope limit (default is 62 mV/pH). Note: A slope of 62
mV/pH or greater indicates that there has been an error made during calibration or
a faulty pH sensor.
3. Replace sensor.
4 – More Status available
4 / 1
ph Slope Too low / Warning
The pH slope calculated during buffer calibration was below the minimum slope
limit. The pH electrode may be worn out, damaged, or coated.
1. Check and clean sensor, then retry buffer calibration.
2. Decrease minimum slope limit (default is 40 mV/pH). Note that a pH sensor
with a slope less than 50 mV/pH is usually near the end of its useful life.
3. Replace sensor.
4 – More Status available
4 / 2
zero Offset Error / Warning
The zero offset from a buffer calibration or single point standardization has
exceeded the limit. The reference electrode may be poisoned or plugged.
1. Check and clean sensor, then retry buffer calibration.
2. Increase maximum offset limit (default is 60 mV). Note that a pH sensor with an
offset of 60 mV or greater is likely poisoned and has to be replaced.
3. Replace sensor.
4 – More Status available
4 / 3
Calibration Error / Warning
4 – More Status available
5 / 4
ph Standardization In progress / Other
A pH standardization is being or has been performed.
4 – More Status available
5 / 5
Buffer Calibration In progress / Other
A pH buffer calibration is being or has been performed.
4 – More Status available
5 / 6
Stabilization In progress / Other
A pH sensor is stabilizing or has been stabilizing.
4 – More Status available
