Quantum Instruments Cascade Laser Starter Kit - Manual (Page 52)

Starter Kit Instruction Manual Maintenance 51
Current adjustment
[28] Set the selector (3) to mode Setting ◦ C
and adjust the temperature value to 25 ◦ C
by means of the Set Temperature 5 tuns
portentiometer P8 (2).
[29] On the external power supply, rise slowly
the voltage 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 temperature 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 temperature reference to -25
◦ C and check the displayed current.
1
Fig.47: TCU151 main board
TCU151
Tem
pera
ture
Con
trolle
r
Alar
m
Res
et
Exte
rnal
Inte
rnal
Rea
l I
Rea
l C Setti
ng
C
Setti
ng
+I
Setti
ng
−I
+
−
5
4
3
2
Fig.48: TCU151 front panel