Instruction manual

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MODEL Xmt-A-F/FI SECTION 15.0
TROUBLESHOOTING
15.2.11 EE Buffer Overflow
EE Buffer Overflow means the software is trying to change too many background variables at once. Remove power
from the transmitter for about 30 seconds. If the warning message does not disappear once power is restored, call the
factory for assistance.
15.2.12 EE Chksum Error
EE Chksum Error means a software setting changed when it was not supposed to. The EEPROM may be going bad.
Call the factory for assistance.
15.2.13 EE Write Error
EE Write Error usually means at least one byte in the EEPROM has gone bad. Try entering the data again. If the error
message continues to appear, call the factory for assistance.
15.2.14 Sense Line Open
Most Rosemount Analytical sensors use a Pt100 or Pt1000 in a three-wire configuration. The in and return leads con-
nect the RTD to the measuring circuit in the analyzer. A third wire, called the sense line, is connected to the return lead.
The sense line allows the analyzer to correct for the resistance of the in and return leads and to correct for changes
in lead wire resistance with changes in ambient temperature.
1. Verify all wiring connections, including wiring in a junction box, if one is being used.
2. Disconnect the RTD SENSE and RTD RETURN wires. Measure the resistance between the leads. It should be
less than 5 ohm. If the sense line is open, replace the sensor as soon as possible.
3. The transmitter can be operated with the sense line open. The measurement will be less accurate because the
transmitter can no longer compensate for lead wire resistance. However, if the sensor is to be used at approxi-
mately constant ambient temperature, the lead wire resistance error can be eliminated by calibrating the sensor at
the measurement temperature. Errors caused b changes in ambient temperature cannot be eliminated. To make
the error message disappear, connect the RTD SENSE and RETURN terminals with a jumper.
15.3 TROUBLESHOOTING WHEN NO FAULT MESSAGE IS SHOWING - TEMPERATURE
15.3.1 Temperature measured by standard was more than 1°C different from controller.
A. Is the standard thermometer, RTD, or thermistor accurate? General purpose liquid-in-glass thermometers, partic-
ularly ones that have been mistreated, can have surprisingly large errors.
B. Is the temperature element in the sensor completely submerged in the liquid?
C. Is the standard temperature sensor submerged to the correct level?
15.4 TROUBLESHOOTING WHEN NO FAULT MESSAGE IS SHOWING - OXYGEN
Problem See Section
Zero current was accepted, but current is greater than the value in the table in Section 7.2 15.4.1
Error or warning message while zeroing the sensor (zero current is too high) 15.4.1
Zero reading is unstable 15.4.2
Sensor can be calibrated, but current is outside the range in the table in Section 7.3 15.4.3
Possible error warning during air calibration 15.4.3
Possible error warning during in-process calibration 15.4.4
Process readings are erratic 15.4.5
Readings drift 15.4.6
Sensor does not respond to changes in oxygen level 15.4.7
Readings are too low 15.4.8