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The Deltalab strain bridge has six independant channels. It is designed for measuring strains using standard strain gauges. It can also be used for measuring other parameters with the appropriate transducers.


The high-contrast digital display gives a direct reading in micro-strains, for half or full bridge operation of the six channels. Measurements with a quarter bridge configuration can be made by adding a resistor. The gauge factor can be adjusted between 1 and 5. Each channel can be balanced separately by means of multiturn potentiometers.
An analogue output for each channel permits the display of the signals using an oscilloscope or a plotter, and also data acquisition.
With the bridge energisation of 2.5 V, strain gauges of 120 W minimum can be used. These can be in Constantan, Isoelastic Karma or Platinum - Tungsten alloys.
The 20 000 point digital display allows measurements in the range ± 20 000 mm/m, whatever the gauge alloy.


Technical specifications

Number of channels: 6
Operating range: ± 20 000 µm/m
Resolution: ± 1 µm/m
Bridge energisation: 2.5 V - Stability: 10-4
Gauge configuration: Full or half bridge with gauges of 120 to 5000 WQuarter bridge with additional resistor
Input impedance: 1010 W
Balance: using multi-turn potentiometers ± 2000 µW/W
Gauge factor read directly on display adjustable from 1 to 5 by multi-turn locking potentimeters.resolution: 0.001
Amplifier: precision 1 %
linearity: ± 0.002 %drift: 0.25µV/°C noise: less than 13µV per Hzcommon mode rejection:< 100 dB
Analogue outputs: independant output for the 6 channels, using Cannon 9 pin connectors max. output voltage: 10 V band pass: 0 - 10 kHz
2 V for 20000 µW/W
minimal load: 22000 W
Gauge connections: 15 pin Cannon connectors24 way rapid connector

Data acquisition and processing system EI617
With an IBM-PC or compatible micro-computer, the system can configure and read the six channels simultaneously. It comprises three elements:

· Software package EI626 :
Allows for each series of measurements :
- test identification
- strain bridge initialisation
- channel selection, gain, configuration (full or half-bridge), gauge factor, graph configuration, sampling rate, total number of acquisitions.
- visualisation
- safeguard
- print-out
- saving test to file

· Card-bridge connecting cable, EI692

· Analogue / Digital acquisition card, EI690 :
Features :
- reads 16 single analogue inputs or 8 differential analogue inputs
- 12 bit digital conversion, or a resolution of 4096 points full scale
- accepts maximum voltages of 0 to 10 volts in unipolar mode and ± 5 volts in bi-polar mode
- fixed frequency acquisition, through built-in time


Dimensions and weight

- 265 x 105 x 84 mm

- Net weight : 1.8 Kg

Essential requirements

Voltage : 220 V, 50 or 60 Hz