© 2022
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WTC32ND TEMPERATURE CONTROLLER
TROUBLESHOOTING, continued
PROBLEM
POTENTIAL CAUSES
SOLUTIONS
Temperature takes too long
to reach setpoint
Temperature sensor may be
too far from the thermoelectric
Avoid placing the temperature sensor physically far from the
thermoelectric. This is typically the cause for long thermal lag and
creates a sluggish thermal response that produces considerable
temperature overshoot near the desired operating temperature.
Current limit may be set too low
Increase the current limit but DO NOT exceed the specifications of the
TEC or heater.
The WTC32ND-EV is not
producing current
The P GAIN or I TERM may
be turned all the way counter
clockwise (CCW)
Turn the P GAIN and I TERM trimpot screws clockwise to the setting
The setpoint is 1 V higher
than it should be when
using the HSET input
The VSET SOURCE jumper
may be still in place
Remove the VSET jumper to use HSET input.
Overshoot with Small
Loads
The I TERM may be
overcompensating
With small, fast loads, the WTC has a tendency to overshoot by up to
10°C. This problem is caused by overcompensation by the integrator.
Take the I TERM out of the system by placing a shorting jumper between
Pin 6 (+1V) and Pin 7 (I)
