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3.2 – Programming of Load cell input
Refer to cell manufacturer’s documentation, particularly with
respect to the cell sensitivity and supply voltage specifications.
As load cell indicator, the meter’s function is to measure forces
(weight, pressure, torque...) applied to a sensing element
connected to several bridge type transducers, such as load cell,
which supply signal levels up to ±150 mV.
The two excitation voltages supplied by this instrument are 10 V
and 5 V. The selection is realised through the configuration of the
internal bridge excitation (see diagram below). This way up to 2
cells can be connected in parallel with 10 V excitation and up to 4
cells with 5 V excitation, without need for an external source (see
connection (Sec. 3.2.1)).
Example:
2 cells with 2 mV/V output are supplied with an excitation
voltage of 10 V; the voltage generated by each cell at full
load is 20 mV. Therefore 20 mV is the maximum output as
the cells are connected in parallel. In the same case but
with a 5 V excitation, the maximum voltage generated will
be 10 mV.
Software configuration requires programming of the input mV range
which can be selected from a choice of 3 ranges to avoid ‘out of
range’ signals. There are three ranges: ±15 mV, ±30 mV and ±150
mV
Example:
If a weighing process gives 12 mV to the meter input with
maximum load, the best input range to select will be "15 mV".
Selection of voltage excitation 10 V or 5 V
5 V Exc. Jumper on
10 V Exc. Jumper off
