Carrier PC211 Start-Up, Operation And Maintenance Instructions Manual page 230

Click here for Table 11A — Thermistor Temperature (F) vs Resistance/Voltage Drop
Click here for Table 11B — Thermistor Temperature (C) vs Resistance/Voltage Drop
Control Modules
CAUTION
Turn controller power off before servicing controls. This ensures safety and pre-
vents damage to controller.
The Processor module (PSIO), 8-input (Options) modules, Starter Management Module
(SMM), and the Local Interface Device (LID) module perform continuous diagnostic evaluations
of the hardware to determine its condition. Proper operation of all modules is indicated by LEDs
(light-emitting diodes) located on the side of the LID, and on the top horizontal surface of the
PSIO, SMM, and 8-input modules.
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CAUTION