Properties

Depending on the thin film that is used, foil strain gauges (SG) are implemented which achieve a gauge factor of up to 30. Depending on the corresponding requirements, specific thin films can be quoted or developed to satisfy the needs of the particular application. Besides the gauge factor, the focus lies on stability, temperature-sensitivity and, of course, reproducibility.

The possible characteristics at a glance:

  • gauge factor between 2 and 30
  • linear signal strain behaviour
  • adjustable temperature coefficient of the electrical resistance (TCR)
  • electrical resistance adjustable from 120 to 500.000 ohms
  • transverse sensitivity of the thin film of 0% to 50%

Our technical department will be glad to answer any of your questions. CeLaGo Sensors provides you SG for testing in your application field.

Depending on the requirements, a large diversity of SG is available.

 

Description of the strain gauge article number

1 - X - SA - MA - XX - GG.GG - RR.RR _ X
 product group  

thin film material/

adjustment

  measuring grid arrangement   type    grid length    resistance   supplement (optional)

 

 

Thin film material (S)

The possible film characteristics at a glance:

Code (S) Thin film material Properties*  Possible applications
 W NiCr
  • gauge factor=2
  • linear signal strain behaviour
  • adjustable temperature coefficient of the electrical resistance
  • design dependent resistance starting with 120 ohms
industrial transducer, weighing, etc.
S modified NiCr
  • gauge factor=10
  • linear signal strain behaviour
  • adjustable temperature coefficient of the electrical resistance
  • design dependent resistance from 350 ohms
  • transverse sensitivity of the thin film up to 50%
  • compared to the modified Ni with improved stability and creep behaviour
  • creep compensation possible
industrial transducer, etc.
U modified Ni
  • gauge factor=10...30
  • linear signal strain behaviour
  • adjustable temperature coefficient of the electrical resistance
  • design dependent resistance from 350 ohms
  • transverse sensitivity of the thin film up to 50%
dynamic measurements, short-term use

*the gauge factor can variate up to 1 dependent on design and compensation

 

Adjustment (A)

By compensating the apparent strain due to the thermal expansion of the transducer, the temperature sensitivity of the single resistor can already be decisively suppressed. Adjustments to the following coefficients of expansion of the transducer material are available:

Code (S) Adjustment to**
A

0,5 ppm/K

B

5,4 ppm/K

C 9 ppm/K
D 10,9 ppm/K
E 16 ppm/K
F 23 ppm/K

**Due to the production the adjustment accurancy is 3 ppm/K.

 

Measuring grid arrangement (MA) and types (XX)

In addition to a number of standardized layouts, customer-specific designs can also be supplied. The classification of the measuring grid arrangements is according to the table:

Code (MA) Type of strain gage
Overview of the types***
LM

linear pattern

See the overview of linear pattern
SM

shear pattern

See the overview of shear pattern
TR T-rosette See the overview of T-rosette
VB full bridge only customized
MR membrane rosette only customized 

***Available as standard

 

Grid arrangement (GG.GG) and resistance (RR.RR)

Code (GG.GG) Grid length
Code (RR.RR) Resistance
00.80 0.8 mm

00.35

350 ohms
01.57 1.57 mm

01.00

1.000 ohms
02.80 2.8 mm 50.00 50k ohms
... ... ... ...

Supplement (X)

Code (X) Special feature
E

samples

R  right alignment (shear SG)
L  left alignment (shear SG)
RL double-SG with right and left alignment (shear SG)
S  customer-specific design
D  double-SG