Operator`s manual

83 Signametrics
DMMReadCJTemp
SM
Description Read cold junction temperature for thermocouple measurement.
include "sm204032.h"
int DMMReadCJTemp(int nDmm, double *lpdTemp)
Remarks ead the cold juncion temperature sensor for subsequent thrermocouple measurements.
When measuring temperature using thermocouples it is necessary to establish a reference
is
CJTemp()
function reads the sensor output voltage (0 to +/-3.3V), and converts it to cold junction
perature usi tion Temp = b + (Vcjs – a)/m. The default values of a,
b and m are designed specifically for the temperarute sensor of the SM40T terminal
block. The valu
thermocouple measurements as well as return at the location pointed to by lpdTemp.
Parame
2040 ; SM2042 ; SM2044 ;
#
R
or cold junction temperaturem. This is the temperature at which the themocouple wires
are connected to the DMM or to the switching card’s cooper wires. One way to do this
by measuring the cold junction sensor using this function. DMMRead
tem ng the built in equa
e of the cold junction temperature is saved internally for subsequent
ter Type/Description
nDmm
int Identifies the DMM. DMMs are numbered starting with zero.
old the temperature.
Return Value rn valu
lpdTemp
double * Points to the location to h
The retu e is one of the following constants.
Value Meaning
DMM_OKAY
Operation suc
Error code.
cessfully terminated
Negative Value
Exa JTemp(0, &temp);
eadCre
SM2040  SM2042 ; SM2044 ;
Description
#include "sm204032.h"
mple DMMReadC
DMMR stFactor
Return ACV signal’s Crest Factor.
int DMMReadCrestFactor(int nDmm, double *lpdResult)