Cable Shortening Or Extension; Connection In A Four-Wire Configuration; Emc Protection - HBM U10M Montageanleitung

8.2

Cable shortening or extension

The cable can be shortened or extended in versions with fixed cables. Use
shielded, low-capacitance measurement cables only for extension (see also
Section 8.4). Ensure that connection is perfect with a low contact
resistance and connect the cable shield. We recommend running the extension
as a six-wire circuit, so that the rated output does not change.
Important
The transducer degree of protection can drop if the cable connection does not
have the same sealing as the
transducer.
8.3

Connection in a four-wire configuration

When transducers in a six-wire configuration are connected to amplifiers in a
four-wire configuration, the sense leads of the transducers must be connected
to the corresponding excitation voltage leads: marking (+) with (+) and marking
(-) with (-), see Fig. 8.1. This measure also reduces the cable resistance of the
excitation voltage leads. If you use an amplifier with a 4-wire circuit, the output
signal and the temperature dependence of the output signal (TCS) depend on
the length of the cable and the temperature. If you use the 4-wire circuit as de­
scribed above, this will result in slightly higher measurement errors. An ampli­
fier system working with a 6-wire circuit ensures perfect compensation for
these effects.
8.4

EMC protection

Electrical and magnetic fields often induce interference voltages in the measur­
ing circuit. Therefore:
S Use shielded, low-capacitance measurement cables only (HBM cables fulfill
both conditions).
S Do not route the measurement cables parallel to power lines and control
circuits. If this is not possible, protect the measurement cable with a steel
conduit, for example.
U10M/U10S
A01385_06_YIC_06 HBM: public
Electrical connection
29