IMC C SERIES User Manual page 118

118 Device description
5.8.3.2 Ground-referenced current measurement
5.8.3.3 2-wire for sensors with a current signal and variable supply
Terminals +VB and +I; ¼Bridge.
The signal is measured by the unit between +IN and -VB. For this reason, a wire jumper must be
positioned between Pins +IN and +I; ¼Bridge inside the connector pod.
© 2018 imc Test & Measurement GmbH
·
Current: e.g. ±50 mA to ±1 mA
In this circuit, the current to be measured flows through
the 120 Ω shunt in the amplifier. Note that here, the
terminal -VB is simultaneously the device's ground. Thus,
the measurement carried out is single-end or ground
referenced. The potential of the current source itself
may be brought into line with that of the units ground. In
that case, be sure that the device unit itself is grounded.
In the settings interface, set the measurement mode to
Current.
Note that the jumper between +IN and +I; ¼Bridge
should be connected right inside the connector.
·
For an (optional) sensor supply with ±15 V ground
referenced current measurement is not possible. The
pin I;¼Bridge is used as -15 V pin.
·
For the former C-70xx equipped with a 350 Ω quarter
bridge completion, ground referenced current
measurement is not possible!
·
e.g. for pressure transducers 4 mA to
20 mA.
Transducers which translate the physical
measurement quantity into their own
current consumption and which allow
variable supply voltages can be configured
in a two-wire circuit. In this case, the
device has its own power supply and
measures the current signal.
In the settings dialog on the index card
Universal amplifiers / General, a supply
voltage is set for the sensors, usually 24 V.
The channels must be configured for
Current measurement.
The sensor is supplied with power via
Note
imc C-SERIES - Manual, Version 4 R 3 - 2018-10-19
Note