REMOTE SCALE CONNECTION
The cable for the load cell goes to a 9 pin D-subminiature plug connector
with the following connections:
Pin numbers Connection
Pins 1,2 - Excitation (0 V)
Pins 4,5 + Excitation (+5 V)
Pin 7 + Signal
Pin 8 - Signal
(The sense wires connections of a six wire load cell are not used but can be
connected to the respective Excitation pins).
REMOTE SCALE SET UP
The remote scale should set for a realistic resolution with respect to the
input provided by the load cell/s.
If a single 2 mV / V load cell is fitted and more than 60% of the load cell is
used for full capacity then the high output of >6 mV span makes it possible
to set a high resolution.
If this criterion is met then the remote scale can be set to a high resolution
with a maximum of 1:30,000, i.e. 300 kg x 0.01 kg.
It will also be possible to sample on the remote scale with the same
accuracy as the Local.
Where more than one load cell is fitted or the total load cell capacity is not
utilised then a reduced resolution should be selected in the remote scale
technical set up. For example, if a system uses four 2 mV / V 1000 kg load
cells for a scale of 1000 kg capacity then the span output at full scale will be
only 2.5 mV.
In this situation the resolution should be reduced to give a good number of
ADC counts per displayed division, i.e., set to 1:5000 or 1000 kg x 0.2 kg.
Setting a high resolution without providing a good input to the remote scale
ADC will not give better accuracy and may make the scale difficult to meet
performance specification.
For best performance ensure a minimum of 0.1 µV / d.
© Adam Equipment Company 2007
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