Burster 9243 - Output of the Sensor; Parallel Connection of Sensors

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10.3 Output of the sensor
An important criterion for determining the gain is the measuring voltage supplied by the sensor
in use. In this respect, the sensor specification format usually varies from one manufacturer to
another.
A strain-gauge full-bridge sensor can have the following specifications, for example:
• Excitation: 5 V
Output: 2 mV/V
• Sensor excitation: 10 V
Output voltage: 10 mV
• Reference voltage: 5 V
Sensitivity: 2 mV/V
In all 3 examples, the sensor output voltage at full deflection is 10 mV.
10.4 Parallel connection of sensors
For certain weighing applications, it is expedient to operate several strain-gauge full-bridge
sensors connected in parallel. For this purpose, the feed lines, measuring lines and sensor lines
are connected in parallel in each case. The sensors then act as a single electrical unit.
A prerequisite here is that all sensors should be completely identical in terms of their:
• Characteristic value
• Input resistance
• Output resistance
If this is not the case, then this technique could give rise to errors.
CAUTION
Ensure that the maximum permissible current is not exceeded.
Voltage
Number of 350 Ω sensors
2,5 V
4
5 V
2
10 V
1
Table 3: Parallel-connected sensors
Note: This does not apply to sensors in conjunction with safety barriers.