VTI Instruments EX1629, User Manual

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VTI Instruments Corp.
260 EX1629 Command Set
vtex1629_set_half_bridge_lead_wire_desensitization
F
UNCTION
P
ROTOTYPE
ViStatus vtex1629_set_half_bridge_lead_wire_desensitization (ViSession vi , ViInt32 channelsArraySize , ViInt32
_VI_FAR channels[] , ViReal64 _VI_FAR factor[] );
F
UNCTION
P
ARAMETERS
vi = contains a session handle to the instrument. This handle is obtained by the function and remains valid until the
session is closed.
channelsArraySize = the size of the channel[] array. Valid input values: VTEX1629_MIN_SCANLIST_LENGTH
(1) to VTEX1629_MAX_SCANLIST_LENGTH (48).
channel[] = an integer input array that specifies the channels to which the factor parameter will apply. Valid input
values: 0 to 47.
factor = an input array of values which set the desensitization error for the channels indicated in the channels[]
array. Valid input values are number greater than 1.
D
ATA
I
TEM
R
ESET
V
ALUE
factor = 1
D
ESCRIPTION
This function sets the lead wire desensitization factor for a given list of channels. The factor parameter is defined as
follows:
gage
lead
R
R
factor 1
where R
lead
represents the resistance of the lead and R
gage
is the resistance of the strain gage.
NOTE Early EX1629s do not have hardware which supports this functionality. Implementation of direct
lead wire measurement is not possible on first generation units.
E
XAMPLE
ViSession instrumentHandle;
ViStatus status;
ViInt32 channelsArraySize = MAX_CHANNELS;
ViInt32 channels[MAX_CHANNELS];
ViReal64 factor[MAX_CHANNELS];
ViInt32 i = 0;
for(i = 0; i < channelsArraySize; i++) {
channels[i] = i;
}
status = vtex1629_set_half_bridge_lead_wire_desensitization(vi,
channelsArraySize,
channels,
factor);