Weidmuller STG - Bridge measuring transducer - Handbuch (Seite 16)

16
Bridgeexcitationsupply
The STG provides the bridge excitation voltage using remote sensing
techniques to compensate for cabling and contact resistance. We
recommended this option for all new installations or where an upgrade
to 6-wire operation is possible. Remote sensing wiring requires three
twisted pairs.
If you install the bridge without remote sensing, adjusting the EX
control will give the correct voltage at the bridge after installation.
TAREadjustment
The installed strain gauge is normally subjected to an initial load
independent of the measurement taken. The TARE adjustment and test
points allow you to correct for this initial loading. The procedure tare
adjustment is as follows:
1. Remove the load to be measured from the Load cell/Strain gauge
bridge.
. Measure the voltage across the test points (TARE+ and TARE–).
. Adjust the TARE control until the voltage across the test points is
0.00 mV. Note: It is possible to over adjust the TARE control so that
the unit will give zero output until a certain weight is reached. Adjust
the control until the voltage reaches 0.00 mV and no further.
For best results, give the instrument and strain gauge about fifteen
minutes to reach a stable temperature.
Connections
For effective protection from electromagnetic noise, all signal cables
must be shielded, or located on conductive trays or in conduits.