HBM U10M, Mounting Instructions, Page: 23 / 128

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U10M, U10S
A1385-6.2 en/de/fr HBM
With this cable assignment, the output voltage at the measuring amplifier is
positive in the tensile direction when the transducer is loaded.
The cable shield is connected with the transducer housing. Only use plugs
that meet EMC guidelines. The shielding must be connected extensively. With
other connection techniques, an EMC‐proof shield should be applied in the
wire area and this shielding should also be connected extensively (also see
HBM Greenline Information, brochure i1577).
6.2 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 6.4). Ensure that connection is perfect with a low contact resistance
and connect the cable shield. We recommend implementing extensions using
six‐wire configuration to exclude changes to the sensitivity.
Important
The transducer degree of protection can drop if the cable connection does not
have the same density as the transducer.
6.3 Connection with four‐wire configuration
When transducers with a six‐wire configuration are connected to amplifiers
with a four‐wire configuration, the sense leads of the transducer must be con­
nected to the corresponding supply leads: Identification (+) with (+) and identi­
fication (-) with (-), see Fig. 6.1. This measure also reduces the cable resist­
ance of the excitation voltage leads. However, there will be a voltage loss on
the supply leads due to the cable resistance that is still present and not com­
pensated for by the six‐wire configuration. A large part of this loss can be
eliminated by a calibration, however, the temperature‐dependent part remains.
The TK
c
value given in the specifications for the transducer therefore does not
apply for the cable and transducer combination when connection is with
four‐wire configuration, the cable percentage must be added.
6.4 EMC protection
Electrical and magnetic fields often induce interference voltages in the meas­
uring circuit. Therefore:

Use shielded, low‐capacitance measurement cables only (HBM cables
fulfill both conditions).