Self-Test - VTI Instruments Metek EX1202 User Manual

Programming Interface
The VTEX DMM and VTEX Scanner drivers provide the access to the features of EX1200 DMM.
Refer to the below functions of the driver in its documentation.
IVTEXDmmTemperature Interface
IIviDmmTemperature..::.Thermistor Property
Scanlist Application Note
When using scanlist with temperature measurements, it is important not to make any configuration
modification between running the scan list and reading the data. For example, using the following
sequence would result in an erroneous reading:
1) Set up config "CJC" with 10k thermistor
2) Run scanlist
3) Change "CJC" to use 5k thermistor instead
4) Read back data
The EX1200 performs the needed temperature calculation based on the current settings. As a
result, the data taken with the 10k thermistor would have 5k-related math applied, resulting in
incorrect data. In the same respect, if the temperature configurations are deleted after the scan list
is run and the user attempts to read the data, an "Bad Configuration Index" error will occur. This is
the result of the EX1200 attempting to perform calculations without configuration data.
S -T
ELF EST
The EX1200 DMM self-test performs various hardware checks to ensure that the DMM is
functioning properly. The process is takes approximately two minutes to complete and checks the
following:

Communication lines for the controller board, digital FPGA, and analog FPGA.

SRAM memory

Power supply, fuse, and shut down capabilities

Onboard temperature sensor

DCV analog path

DC protection circuit

DCI analog path

Current input fuse

2- and 4- wire resistance, ohms overload

ADC overload

Frequency testing

ACV testing
Basic EX1200 DMM Operation
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