Checking The Rtd; C Hec Kin G Th E Rt D - Conair Thermolator TW-S User Manual

6-30 I Tr o u b l e sh o o ti n g
Ch ec k ing th e RT D
WA R NIN G : Electr i cal Shock Hazar d
Only qualified service personnel who have been trained on electrical testing and
the procedures for avoiding the hazards should diagnose or correct problems that
require opening the unit with power on.
The Thermolator uses a Pt100 RTD to monitor the "to process" and "from process"
temperature. One Pt 100 RTD is installed in the wall of the heater tank at the "to pro-
cess" outlet. The other is installed in the mixing tank (or heat exchange) near the "from
process" outlet.
Sensor error codes (Er.) displayed by the temperature controller may indicate RTD
failure.
To check a RTD after a sensor error:
1
Disconnect and lockout the main power.
2
Open the electrical enclosure door. Turn the screw on the front panel counterclock-
wise to open.
3
Remove RTD wiring terminal strip. Refer to the wiring diagrams that came with
your unit.
4
Verify the resistance of the RTD using a VOM. Polarity does not matter. If in-
correct, replace.
Refer to the table on the nest page.
(Continued)