- Quantum Cascade Laser Starter Kit Instructions Manual

Starter Kit Instruction Manual Maintenance 51
Current adjustment
[28] Set the selector (3) to mode Setting
◦
C
and adjust the temper ature value to 25
◦
C
by means of the Set Temperature 5 tuns
portentiometer P8 (2).
[29] On the external power supply, rise slowly
the voltag e to 30 V and the current to 1.5 A.
,→ The tension should stabilize at 30 V
Note: If the current is too high, stop the test
and verify the transistors Q1 to Q4 (1) and
their associated resistors.
There might be a soldering problem. In this
case, fix it and repeat the procedure from step
[10].
[30] Set the selector (3) to mode Real I.
,→ Value displayed: ≤ 1A.
[31] Set the selector (3) to mode Real
◦
C.
,→ Value displayed should tend to the defined
value.
[32] Wait for a certain time and check the
Peltier tempera ture with a thermometer
[33] Set the selector (3) to mode Setting +I.
[34] Increase the limit of positive current to
3.5A by means of the +I trimmer (4) located
on the front panel.
[35] Increase the limit of negative current to
5A by means of the -I trimmer (5) located on
the front panel.
[36] Change the temp e rature reference to -25
◦
C and check the displayed current.
1
Fig.47: TCU 151 main board
TCU151
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Fig.48: TCU 151 front panel