Problem Causes and Solutions
Temperature readout differ
-
ent than expected, e.g. the
heat source is set at 300°C,
the PRT measures 275°C.
•
Measure the PRT resistance at TPW.
•
If the resistance of the PRT is less than the rated resis
-
tance, e.g. 70 Ω for the 5626, there may be a short in
the sensor. Contact an Authorized Hart Scientific Service
Center (see Section 1.3).
•
If the resistance of the PRT is only a few ohms, there
may be a short in the four lead-wires. Contact an Autho
-
rized Hart Scientific Service Center (see Section 1.3).
•
If the PRT is open, the resistance will be “Out of Limits”
or in the kilo-ohm or mega-ohm range. Contact an Au
-
thorized Hart Scientific Service Center (see Section 1.3).
5626/5628
User’s Guide
18
