THORLABS ITC502 - TEC Element Polarity Check

2.14 Polarity check of the TEC element
ITC500 / page 41
2.14 Polarity check of the TEC element
Pre-settings
• Connect TEC element and temperature sensor. The sensor must be in good
thermal contact to the active surface of the TEC element.
• Switch on the ITC5xx.
 Now follow the steps described in chapter 1.8, “Pre-settings“ starting on page 16.
• Select the display T
SET
and select a suitable temperature (resistance).
• Select the display T
ACT.
• Switch on the output (press TEC ON) and observe the actual temperature
(resistance).
 If the temperature T
ACT
is continually running away from T
SET
, The TEC element is
reversed poled. Change polarity and repeat the procedure.
 If T
ACT
is oscillating around the value T
SET
, the TEC element has been connected
correctly, however, the values for the P-, I- and D-share of the control loop are still
incorrect.
 (Refer to chapter 2.15.4, "PID adjustment" starting on page 45)
 If T
ACT
is settling properly to the value T
SET
, the TEC element has been connected
correctly, the values for the P-, I- and D-share of the control loop might still be
improved.
 (Refer to chapter 2.15.4, "PID adjustment" starting on page 45)