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The effective gain factor is approximately 50000.
This applies to the following general relationship.
This results in a minimum input signal of 0.2 mV for the module amplifier.
6.3.2 Fine adjustment
The gain is adjusted finely with the corresponding control on the front panel.
v
Total
= v
Stage1
x v
Stage2
x v
Stage3
x (0.85 ... 1.11)*
*Fine adjustment
6.3.3 Calculating the gain
When calculating the gain, always use U
O
= 10 V as the reference, even if the 5-V output is
required.
Example:
Given: Strain-gauge sensor 350 ohms
Rated characteristic value 1.5 mV/V
Sensor excitation voltage 5 V
Required output voltage U
O
from the amplifier 10V
Wanted: Total gain v
The amplifier input voltage UI generated by the sensor is determined as follows:
U
I
= Rated characteristic value x reference excitation voltage
The relationship
=
=
10
7.5
results in a gain factor v = 1333 in this example. The fine adjustment covers 85 -111% of the
gain adjusted coarsely in stages 1 - 3. In this example, the theoretical gain factor therefore lies
between v = 1133 (85% of 1333) and v = 1480 (111% of 1333).
Calculated total gain: v = 1333 (Stage 1 x Stage 2 x Stage 3)
Set total gain: v = 1300 (100 x 6.5 x 2)
Fine adjustment range: v = 1105 ... 1443 (0.85 x 1300 to 1.11 x 1300)
U
I
= Input signal
U
O
= Output signal
V
Total
= Gain
=
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