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4.2.1 Connecting in 4 or 6 wire technology
The described measuring amplifier allows to connect the transducer in either 4 or 6 wire technology.
The excitation voltage received by the sensor has great influence on the sensors signal. So, if with a
very long cable, or lengthening of it, the excitation voltage drops even by a slight value the signal drops
accordingly. If the amplifier together with the sensor has been factory calibrated a longer cable is not a
problem. But it must not be lengthened. This way the factory calibration is still valid.
It is preferred to connect the sensor in 6 wire technology, if the cable has to be lengthened, because
the 2 additional wires measure the excitation voltage directly at the sensor and the amplifier adjusts
the excitation voltage accordingly.
4.2.2 Connecting in 4 wire technology
Notice:
When connecting in 4 wire technology the jumpers J1 and J2 must be set. Otherwise the
transducer might get damaged resp. destroyed.
The values in the calibration certificate of the sensor have been recorded with the attached cable. So,
this cable must not be shortened, because it would increase the sensor signal and therefore change
the accuracy.
With a sensor without a cable the values of the certificate have been recorded right at the connector. In this case
a connection in 6 wire technology is recommended.
Pic. 1: Connection in 4-wire technology
SG-Amplifier
SG-Signal
Internal jumpers
J1 and J2
+Sense
+SG-Excitation
-Sense
-SG-Excitation
Transducer cable
350 Ohm
