Analyser AutoSPY
®
1
Analyser AutoSPY
Quick Guide to A/D Measuring Device LabJack U12
With the A/D measuring device LabJack U12 you can record up to 8 analog and 20 digital electric
signals in AutoSPY, for instance from switches, light barriers, temperature or pressure sensors. That
allows trouble shooting and optimization to cover electrical signals that are not available in a PLC
directly or that shall be double-checked by independent measurements.
The LabJack can easily be attached to the USB port of the analysis PC and does not require any addi-
tional power supply. Windows comes with the required drivers preinstalled, such that AutoSPY can
instantly access the LabJack. Multiple LabJacks can be operated at different USB ports and recorded
at the same time in AutoSPY, if you need to measure more signals than a single unit can handle.
Specification of Measurement Inputs
Analog inputs AI0 through AI7
The LabJack has eight screw terminals AI0 through AI7 for analog input signals. These can measure
voltages up to ± 10 V with respect to ground (GND) with a resolution of 12 bit / 4.88 mV. To do so, at
first the ground and
afterwards
the signal line need to be connected to the corresponding terminals.
Beside this so called single-ended measurement, the LabJack is capable of measuring the input pairs
AI0/1, AI2/3, AI4/5 and AI6/7 in differential mode. As stated in the following table, each of these four
differential channels can provide a gain of up to 20 to achieve a higher effective measurement resolu-
tion for smaller voltage ranges.
Gain G
Maximum voltage
between AI and GND
Maximum differential
voltage
Measurement resolution
1
± 10 V
± 20 V
4.88 mV
2
± 5 V
± 10 V
2.44 mV
4
± 2.5 V
± 5 V
1.22 mV
5
± 2 V
± 4 V
0.98 mV
8
± 1.25 V
± 2.5 V
0.61 mV
10
± 1 V
± 2 V
0.49 mV
16
± 0.625 V
± 1.25 V
0.31 mV
20
± 0.5 V
± 1 V
0.24 mV
A/D measurement
unit LabJack U12
Digital extension module CB25
