Specifications

Measurements with Downloaded Unstrained References

In certain applications, it may not be possible to measure unstrained

references ((Vout/Vs)unstrained) prior to making the actual strain

measurements. A feature of the strain gage multiplexers is the ability to

measure unstrained references, store the references in a computer, and then

download them at the time the strain measurements are made.

The following example shows how unstrained references are measured,

stored in a computer, and then downloaded when the strain measurements

are made.

!Dimension computer variables to store the unstrained reference measurements

!and strain measurements.

DIM Unstr(0:2),Strn_rdgs(0:2)

!Clear and reset the multimeter.

CLEAR 70903

OUTPUT 70903;"*RST"

!With the specimen in an unstrained state, call the subprogram which measures

!the unstrained references for each channel. Store the references in a computer

!variable.

CALL Ref_meas(Unstr(*))

!Once the specimen is in a strained state, the strain measurements can be made.

PAUSE

!Make three sets of strain measurements. For each set, specify the gage factor,

!download the unstrained references and then measure the strain. Enter and

!display the readings.

OUTPUT 70903;"STR:GFAC 2.11E-6,(@100:102)"

CALL Ref_load(Unstr(*))

FOR J=1 TO 5

OUTPUT 70903;"MEAS:STR:QUAR? (@100:102)"

ENTER 70903;Strn_rdgs(*)

PRINT Strn_rdgs(*)

NEXT J

WAIT 5