TE Technology TC-24-12 - Manual (Page 7)

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fault condition occurs. Thus, a load circuit may be placed between pins 1&2 and pins 3&4, and
the load will be energized when a fault condition is detected. The drain re-opens and the load
circuit will be de-energized when the fault condition is cleared. The maximum current for the
alarm circuit is 2.5 amps. Because the power to the alarm circuit is supplied by the input power
to the controller and the maximum input current to the controller is limited to 12 amps, any
current supplied to the alarm circuit will cause a likewise reduction in the total output power
available to the thermoelectric load. See section titled “Input/Output Connector” for additional
reference.
NOTES:
When actuating an inductive load such as a mechanical relay or solenoid an external clamping
diode must be used in parallel with the inductive load to prevent a reverse inductive-voltage
spike from destroying the output transistor.
The condition of jumper JP4 determines how over-temperature faults are cleared.
10.0 Input/Output Connector
The input and output connections are made through JP3, a detachable connector (Phoenix
Contact part number 1779916). Wires are inserted into each wire opening (located on top of the
connector as shown in the “Component Identification” photo and “Controller Wiring Diagram”).
The wires are then clamped in place by tightening the respective screw on the side of the
terminal.
NOTE:
The connector can be removed by pulling the detachable portion away from the circuit board.
The wire acts as a heat sink for the connector, and the maximum current of 12 A for any pin in
the connector at a 50 °C circuit board temperature can be achieved only when stranded wire with
a conductor cross section of 2.5 square millimeters is used. The wire that is supplied with the
connector is approximately 2 square millimeters in cross sectional area (for ease of handling
purposes). If you plan to operate the controller so the required input current is 12 A, be sure to
replace the standard wire with wire of the appropriate size for this current draw. The controller’s
electronics take less than 100 mA of current, so the combined output current to the TE load and
alarm circuit should not exceed 11.9 A.