© 2022
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WTC32ND TEMPERATURE CONTROLLER
CHANGING LIM TO A FIXED VALUE
• Connect an ohmmeter to TP1 & TP3, without the
WTC32ND installed.
• Measure the LIMA trimpot value across pins TP1 &
TP3.
• Remove resistor LA2.
•
Load LA1 with a fixed value to match the trimpot
resistance at the proper limit setting (1206 size).
• Repeat with LB2 and LB1 and TP4 & TP1, respectively.
TOP VIEW -- TEST POINT LOCATIONS
BOTTOM VIEW -- RESISTOR LOCATIONS
Figure 32. LIMA & LIMB Settings
CHANGING ONBOARD SETPOINT TRIMPOT TO
A FIXED RESISTANCE
• Connect an ohmmeter to TP1 & TP2, without the
WTC32ND installed.
• Measure the SET T trimpot value across pins TP1 &
TP2.
• Remove resistors ST3 and ST4.
• Load ST1 and ST2 such that:
Equation 15.
Setpoint Resistance
Setpoint = 2.5 * ST2
ST1 + ST2
where:
ST1 + ST2 must be greater than 5 kΩ.
Setpoint is in Volts.
ST1 and ST2 are in Ohms (1206 size).
Figure 33. Test Point Locations
