XITRON 2000I, User Manual

Page: 41 / 96

Operating the 2000 Instrument 41
non-volatile, thus may be selected prior to use, even if the instrument is to be
powered down. This option is available in the 2000M only.
Thermocouple Simulation and Measurement Set-Up
The 2000M instrument’s thermocouple simulation capability is achieved by
setting the desired simulation parameters and then commanding the required
temperature outputs. Setting the simulation parameters involves the selection
of the desired thermocouple type, the method of cold junction compensation,
and the cold junction temperature (if “Passive CJ” has been selected).
Selecting the thermocouple type involves the using the command shortcut
character T followed by the thermocouple type character. For example if a K
or a N type simulation was required, then the string “TK” or “TN”
respectively, would be transmitted to the instrument.
If Active CJC is required, then transmit the command string “J1” to the
instrument, while passive mode is selected by the “J0” string. When changing
from the active to the passive mode, the previously used passive mode
reference temperature defaults.
Notes: Selecting and deselecting thermocouple simulation is simply
achieved by:
1)
Sending a temperature to the instrument, for example: Send the command
string “+22.89C” to select the thermocouple simulation mode with a
simulated hot junction of +22.89ºC.
2) Sending a voltage or current to the unit: for example: The command
string “+10.0V” will set the output level to +10V, which deselects
thermocouple simulation mode.
Always, the Thermocouple Simulation Set-Up data used is that previously
defined, thus it is not necessary to redefine these parameters for each
simulation temperature. Terminating thermocouple simulation is achieved by
sending the unit a voltage
or current output level command, or by sending the
“V” command string without any numeric data. In this case, the output level
simply stays at the previously Calculated voltage, but terminates
thermocouple simulation.