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Temp Sensing 2
The ITC accepts up to two RTD inputs per channel. In Auto Control Mode, the output
of each circuit will function according to the Temp Sensing Setting. However, when
in Manual Mode, the Output will only consider the Output % as selected by the User.
The following settings and their respective function are available when in AUTO Mode:
• Single – Output is based on the sensed temperature of only one RTD sensor. The
2nd RTD Sensor is not recognized.
• Average – Output is based on the average sensed temperature of the two RTD Sen-
sors. If Average is selected and only one sensor is employed, the unit will sense
an open sensor. See Failed Sensor Operation below.
• Low – Output is based on the lowest sensed temperature of the two RTD Sensors.
If Low is selected and only one sensor is employed, the unit will sense an open
sensor. See Failed Sensor Operation below.
• High – Output is based on the highest sensed temperature of the two RTD Sensors.
If High is selected and only one sensor is employed, the unit will sense an open
sensor. See Failed Sensor Operation.
• Use RTD 1 to control both circuits - The output of circuits 1 & 2 will be governed
by the “RTD1 Input” sensor which is located on the Circuit 1 main ITC board.
Notes:
a. This option is only available on 2 circuit ITC’s
b. The RTD sensor must be connected to “RTD1 Input” on Circuit 1 Main ITC
Board. See customer wiring section.
**IMPORTANT CONSIDERATIONS**
The ITC assumes a failed sensor condition if the realized temperature is either below
-100˚F or above 1500˚F. A failed RTD sensor (shorted or open) will send a faulty sensed
temperature to the controller that exceeds these thresholds. Therefore, the user must
understand the output of the ITC when a sensor fails.
Failed Sensor Operation
1. Single – In Failed (Open or Shorted) RTD condition, the ITC will switch to Manual
Mode. Output will be per specified % by user. Failed Sensor condition will be flash-
ing on the LCD screen and alarm LED will illuminate.
2. Average (when using two RTDs per circuit)
a. Individual Failed RTD (Open or Shorted) – ITC Unit will operate in Auto Mode
with a Single Sensor. The temperature reading from the failed RTD sensor will be
ignored. Failed Sensor condition will be flashing on the LCD screen and alarm
LED will illuminate.
b. When both sensors fail, the ITC will switch to Manual Mode. Output will be per
specified % by user. Failed Sensor condition will be flashing on the LCD screen
and alarm LED will illuminate.
3. Low – Same as Average above.
4. High – Same as Average above.
Failed Sensor Output
When using a single RTD - The ITC will automatically switch into Manual Output Mode
when a Failed Sensor Condition is realized. The output % range is 0% to 100% in 1%
increments.
When using two RTDs, see
Failed Sensor Operation above.
Passwords 1, 2 & 3
Default Security Level Passwords may be changed by the user within the System Menu.
See “Security Levels” above for more detail.
Alarm State
Select normal state of alarm. Choices include Normally Closed (default) or Normally
Open.
Restore to Default
This operation allows the user to clear all custom settings and parameters and restore
the ITC to its original factory state.