TE Technology TC-24-25 - Manual (Page 9)

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2.9 Associated with the ALARM TYPE configuration are the HIGH ALARM SETTING, LOW
ALARM SETTING, and the ALARM DEADBAND settings. If an alarm type has been selected,
enter the desired high and low temperature values that you want to have trigger an alarm condition.
The ALARM DEADBAND option sets the hysteresis of the alarm values from 0.1 degrees to 100
degrees.
2.10 The ALARM LATCH menu key permits the selection of ALARM LATCH OFF or ALARM
LATCH ON. If ALARM LATCH OFF is selected, the controller will automatically reset if the
alarm condition self-corrects when the corresponding temperature returns back to the temperature
defined by the ALARM DEADBAND and alarm setting. If ALARM LATCH ON is selected, the
controller will maintain the alarm condition until it is manually cleared. When ALARM LATCH
ON is selected, and if an alarm condition exists, the alarm latch can be reset by clicking the SEND
LATCH CLEAR button.
2.11 The CHOOSE SENSOR FOR ALARM menu key allows for the selection of either the CONTROL
SENSOR thermistor or the INPUT 2 SENSOR thermistor for the alarm sensing. (Note: The
INPUT 2 SENSOR thermistor cannot be used if you are using a potentiometer or voltage/current
levels to control the set point.) The INPUT 2 SENSOR thermistor can be attached to the heat sink
in order to detect over-temperature conditions.
2.12 The CHOOSE DEG C OR DEG F UNITS menu key permits the selection of displaying °F or °C.
NOTE: The EEPROM WRITE ENABLE, located just below the CONFIGURE SECTION, can be
checked or unchecked depending on your requirements. See Appendix C, command #31, for more
information on EEPROM WRITE ENABLE.
2.13 Review all of the controller configuration selections. If all the configuration selections are correct
for the application, select the Send Box Values button to download these settings to the controller.
3.0 Tuning
3.1 You are now ready to tune the controller. All selections for this portion will occur in the TUNING
section of the controller software. The various constants required by the controller to optimize the
system performance are entered in this section.
3.2 The FIXED SET TEMP is the set temperature value entered in degrees. This temperature must be
within the range of the selected input sensor or the limits of low and high set ranges from the
controller configuration setup. Also, verify that the cooler is capable of safely operating at the
entered set temperature. This is particularly important if you are heating. While you can control to
+100 °C using the standard thermistor, many coolers are rated for at most 80 °C.
If you selected COMPUTER CONTROL in the CONTROL TYPE menu key under the
CONFIGURE section, the values that can be entered in the FIXED SET TEMP box range from
–12.0 to +12.0. This corresponds linearly to a fixed percentage of power output where –12.0 equals
–100% power and +12.0 equals +100% power.