Datasheet

Chapter 7: Maintenance
11. Temperature limit testing
a) Decrease the temperature limit threshold from 0.7 V to 0.3 V.
For more details, see Temperature limit threshold on page 89.
b) Increase the temperature reference to 35
◦
C.
→ When the threshold is overpassed, the red LED (1) in front panel should
light up.
c) Wait the real temperature drops 10
◦
C below the threshold.
d) Reset the instrument with the RESET button (2).
→ The red LED (1) should turn off.
e) Reset the temperature limit threshold to 0.7 V. For more details, see Tem-
perature limit threshold on page 89.
12. Monitoring: check the output voltage on the rear instrument BNC connector (5).
For 35
◦
C, the voltage should be 350 mV.
13. External reference:
a) connect an external power supply to the External Reference BNC con-
nector (6).
b) Set the voltage to 3.5 V.
Set the switch External/Internal (3) to External.
Set the selector (4) to mode Setting
◦
C.
→ The temperature displayed (2) should be 35
◦
C.
Set the selector (4) to mode Real
◦
C.
→ The temperature displayed (2) should follow the reference temperature.
92 QCL user’s manual v3.0