THORLABS ITC4000 Series, Руководство по эксплуатации

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3 Operating the ITC4000 Series
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3.1.10 Setting up the TEC Voltage Measurement
TEC voltage four terminal measurement
If the voltage of the TEC element shall be measured and dis-
played with enhanced accuracy, two additional cables must
be connected directly from the two poles of the TEC element
to pin 2 and 9 of the TEC OUTPUT jack (four terminal meas-
urement, see figure to the left).
If pin 2 and pin 9 are left unconnected, the TEC voltage is
measured internally at the contacts A1 and A2 of the TEC out-
put jack (two terminal measurement). This leads to a meas-
urement error due to the voltage drop along the lines to the
TEC element, so a slightly increased voltage will be displayed.
3.1.11 Connecting Interlock and TEC ON Monitoring
Pin 1 and pin 15 of the "TEC OUTPUT" jack (R16) are test contacts to determine whether a
TEC setup is connected or the connection has been interrupted. These pins must be connected
externally by a wire (total resistance <430
W
). When this “interlock” connection is opened, the
ITC4000 switches off the TEC output current automatically. If the TEC output was off, it cannot
be switched on and an error message “TEC cable connection fault” appears.
If a LED with a 1 k
W
parallel resistor is connected between pin 1 and pin 15 as shown in Figure
15, the interlock connection is interpreted as closed, too. The LED lights up when the TEC cur-
rent output is switched on (TEC ON mode).
Note
The ITC4000 Controllers don't support the “TEC lockout” feature of the Thorlabs laser diode
mounts. These mounts usually have an on-board jumper to bypass the TEC lockout function.
For details please refer to the operating manual of the laser diode mount.