BARTINGTON INSTRUMENTS
Page 14 of 16
A1.2. Recommended connection method
Figure 2. Ideal connection method.
Key to Figure 2:
1
Sensor
5
Signal Ground
2
Host
6
Power Ground
3
Host Power Supply
7
Ground
4
Host Local 0V
Figure 2 illustrates the recommended connection method for users who do not wish to use
Bartington Instruments’ power supplies.
Note:
Using this method is essential when using cables over 10m.
The schematic shows signal and power grounds separated at the Host end. The Host is fitted
with buffer amplifiers configured as Instrumentation Amplifiers (IA), which have two high
impedance inputs, one connected to X, Y or Z and the other to signal ground. An IA produces an
output that is the voltage difference of its input referenced to a local 0V. This 0V reference may be
significantly different to either of the two input voltages to the IA (indicated by VCM in Figure 2).
Consult the manufacturer’s data for the part chosen, to ensure the common-mode range is not
exceeded.
