Specifications

the transducer’s response curve in the form of 512 linear segments whose
end-points fall on the curve. Data points that fall between the end-points are
linearly interpolated. The built-in EU conversions for thermistors, thermocouples,
and RTDs use this type of table.
Custom Thermocouple
EU Conversions
The VT1419A can measure temperature using custom characterized thermocouple wire
of types E, J, K, N, R, S, and T. The custom EU table generated for the individual batch
of thermocouple wire is loaded to the appropriate channels using the
DIAG:CUST:PIEC command (see the Agilent VEE example “eu_1419.vee”). Since
thermocouple EU conversion requires a “reference junction compensation” of the raw
thermocouple voltage, the custom EU table is linked to the channel(s) using the
command [SENSe:]FUNCtion:CUSTom:TCouple <type>[,<range>],(@<ch_list>).
The <type> parameter specifies the type of thermocouple wire so that the correct built-in
table will be used for reference junction compensation. Reference junction
compensation is based on the reference junction temperature at the time the custom
channel is measured. For more information see Thermocouple Reference Temperature
Compensationonpage62.
Custom Reference
Temperature EU
Conversions
The VT1419A can measure reference junction temperatures using custom
characterized RTDs and thermistors. The custom EU table generated for the
individually characterized transducer is loaded to the appropriate channel(s) using
the DIAG:CUST:PIEC command (see the Agilent VEE example “eu_1419.vee”).
Since the EU conversion from this custom EU table is to be considered the
“reference junction temperature”, the channel is linked to this EU table using the
command [SENSe:]FUNCtion:CUSTom:REFerence [<range>,](@<ch_list>).
This command uses the custom EU conversion to generate the reference junction
temperature as explained in the section Thermocouple Reference Temperature
Compensation on page 62.
Creating Conversion
Tables
The VT1419A comes with an Agilent VEE example program that can be used to
generate custom EU tables. See the “eu_1419.vee” example in Chapter 5 for more
information.
Summary The following points describe the capabilities of custom EU conversion:
·
A given channel only has a single active EU conversion table assigned to it.
Changing tables requires loading it with a DIAG:CUST:¼ command.
·
The limit on the number of different custom EU tables that can be loaded in
a VT1419A is the same as the number of channels.
·
Custom tables can provide the same level of accuracy as the built-in tables.
In fact the built-in resistance function uses a linear conversion table and the
built -in temperature functions use the piecewise conversion table.
Compensating for System Offsets
System Wiring Offsets The VT1419A can compensate for offsets in a system’s field wiring. Apply shorts
to channels at the Unit-Under-Test (UUT) end of the field wiring and then execute
the CAL:TARE (@<ch_list>) command. The instrument will measure the voltage
Programming the VT1419A Multifunction
Plus
Compensating for System Offsets
Chapter 3 97
Artisan Technology Group - Quality Instrumentation ... Guaranteed | (888) 88-SOURCE | www.artisantg.com