Data Sheet for Product

TT 184 Temperature Transmitters Technical Instructions
Document Number 155-077P25
February 15, 2022
Siemens Industry, Inc. Page 9
Calibration
Because of variations in lengths of pneumatic tubing, airflow through restrictors,
ambient temperatures, etc., there will be small errors between actual temperature at
sensing element and gauge indication. Adjusting the pointer on the receiver gauge to
agree with the temperature at the sensing element will result in greater accuracy.
Additional suggestions are given in the Table 5.
The only way to determine if the temperature transmitter is out of calibration (either
span adjust or zero adjust) is with an accurate two-temperature bath and an accurate
pressure gauge. Span adjustment or zero adjustment cannot be made in the field
because of the equipment and time required.
Preventive
Maintenance
1. Check yearly to see that temperature at sensing element agrees with temperature
at gauge. See Calibration.
2. Periodically, clean dust from the transmitter body using a soft hairbrush.
3. Temperature transmitters do not require lubrication.
Troubleshooting
Table 5. Troubleshooting Chart.
Complaint
Check
Probable Cause
Corrective Action
Low temperature
indication
Restrictor
Plugged restrictors
Clean and replace if
clogged
Wrong size restrictor
Replace restrictor
Receiver gauge temperature
indication vs. temperature at sensing
element
Receiver gauge out of
calibration
Adjust receiver gauge
Fittings and tubing
Leak in transmitter line
As necessary
Filters
Dirty Filter
Replace filter
Supply pressure
Low supply pressure
As necessary
High temperature
indication
Receiver gauge temperature
indication vs. temperature at sensing
element
Receiver gauge out of
calibration
Adjust receiver gauge
Restrictor used
More than one restrictor used.
Both internal (in receiver-
controller) restrictor and
external restrictor installed
Remove all but one
restricted air supply
Defective gasket on receiver-
controller restrictor
Replace restrictor
Wrong size restrictor
Replace restrictor