Scientech H410 Vector - Manual (Page 30)

30
D
ETECTOR
O
PERATION
W
ITHOUT AN
I
NDICATOR
:
Pyroelectric Detectors:
Standard and SP Models:
Pyroelectric detectors can be operated with a 1MΩ input oscilloscope. The peak voltage shown on the
oscilloscope can be divided by the V/J output sensitivity of the detector to calculate energy.
Astral TM and Large Aperture Calorimeters:
Cable Requirements:
Astral calorimeters are powered up by the indicators. To use an Astral calorimeter without a Scientech
indicator, but with a volt meter or chart recorder, you must apply +/-8VDC to the mini DIN connector as shown
in Figure 6. The voltage output of the calorimeter, from pin 8, should be connected to the positive side of the
DVM or chart recorder. All 3 of the grounds should be tied together at the negative side. Pins 2 and 3 are not
used.
Figure 6
When large aperture calorimeters are used without an indicator their interface module is not used. The output
of the calorimeter is connected directly to the DVM or chart recorder. Large aperture calorimeters do not
require any power. The voltage output is on pin 1 of the DIN connector and should be connected to the positive
side of the DVM or chart recorder. Ground is on pin 3 and should be connected to the negative side. Pin 2 is
not used. Refer to Figure 5.
Operation of Astral  and Large Aperture Calorimeters with a Digital Volt Meter:
Note: Whenever a large aperture calorimeter is used without an indicator the interface module is
not used.
The calorimeters may be used with any digital volt meter (DVM) capable of reading 5 volts full scale.
A. Connect the output of the calorimeter to the DVM.
B. Select the DC volts mode.
C. Direct the laser beam on to the absorbing surface of the calorimeter.
D. When the display of the DVM has stabilized (about 2 minutes), calculate the laser power using the
formula: W = V/S
where:
W = Laser power in watts
V = Voltage reading of the DVM in volts
S = Sensitivity of the calorimeter from page 2.