The following information is for the EMANT300, EMANT380

BRIDGE COMPLETION NETWORK

The Bridge Completion Network is used to complete quarter and half bridge strain gauge circuits.

FEATURES

  • Three 120 ohm resistors
    • Tolerance: 0.1%
    • Temperature Coefficient: +/- 25ppm
    • Power Rating: 0.1W
  • Screw Terminals for easy connection.

STRAIN GAUGE

A strain gauge can be used to measure the strain of an object. The most common type of strain gauge consists of a flexible backing which supports a metallic foil pattern etched onto the backing. As the object is deformed, the foil pattern is deformed, causing its electrical resistance to change. The gauge factor of a strain gauge relates strain to change in electrical resistance. The gauge factor GF is defined by the formula

where RG is the resistance of the undeformed gauge, ΔR is the change in resistance caused by strain, and ε is strain. ΔR is typically in the region of 0.1%. To measure such small resistance changes, a Wheatstone bridge is employed. 3 configurations are used - quarter bridge, half bridge or full bridge. Resistors are used to form the bridge in the quarter bridge and half bridge.

Quarter Bridge Connection

Fig 1: Connecting the strain gauge to the network and Bridge Sensor Adaptor

Strain ε is given by

where

and ΔVO is the change in voltage output of the wheatstone bridge from strained to unstrained (seen at the differential input AIN3, AIN2). VEXC is the excitation voltage.

Half Bridge Connection

Fig 2: Connecting the strain gauges to the network and Bridge Sensor Adaptor

Strain ε is given by

Schematic

Specification (PDF file size 355K)

Price US$8
Status In stock