User Guide

19
HI8931 conductivity controller (see
also page 24).
The 4-core cable has to be con-
nected to the transmitter according
to the label instructions on the 4-
terminal strip.
The regulated D.C. supply required for the proper operation of the
transmitter is "+20V", labeled "+20V" and "COM". The current
(mA) output terminals are labeled "4-20 mA" and "COM".
The transmitter is protected against inversion of supply voltage.
• HI8936 used in conjunction with
an external power supply
Use 2 PVC insulated 2-core cables.
Connect a +20V DC power supply
directly to the terminals labeled
"+20V" and "COM", paying careful attention to polarity (see also
page 24) or if necessary in series with the receiving device.
The regulated D.C. supply required for the proper functioning of
the circuit is marked "+20V" and "COM", and the transmitter
current output is indicated "4-20 mA" and "COM".
The transmitter is protected against inversion of supply voltage.
Max. current required: 40 mA.
• Use of an amplifier
The maximum permissible distance between the power supply unit
and the amplifier is 300 m (1000'). It is not necessary to use a
shielded cable.