Datasheet

38
Thermocouple input mode
In thermocouple input mode, the
U2802A can acquire up to ±100 mV
input signals. Each channel includes
an instrumentation amplifier and a
4 Hz low-pass filter. The low-pass
filter removes unwanted noise from
the thermocouple wires to obtain
accurate measurement data.
Voltage input mode
Alternatively, you can select separate
voltage input modes for each channel.
The channel will be set to bypass the
amplifier and filter, allowing up to ±10
V input signals to be directly routed
to the DAQ device analog input. The
bandwidth in this mode is more than
500 kHz.
Zero mode
In zero mode, the positive and
negative inputs of the instrumentation
amplifier are shorted together. The
voltage measured in this mode
corresponds to the offset voltage
of the channel. You can subtract
this offset voltage from subsequent
thermocouple mode measurements
to increase measurement accuracy.
This mode is only applicable in
thermocouple mode.
Thermocouple compatibility
The U2802A is compatible with a
wide range of standard thermocouple
types defined in the NIST ITS-90
Thermocouple Database. This
includes types J, K, R, S, T, N, E, and
B.
Open thermocouple
detection
The U2802A includes open
thermocouple detection circuitry
to indicate the presence of an open
thermocouple.
Calibration EEPROM
The U2802A gain and offset calibration
factors for each channel are stored in
the EEPROM during factory calibration
and can be retrieved prior to taking
measurements. This on-board EEPROM
also stores the module ID, serial
number, and date of calibration for your
reference. A section of the EEPROM
is also allocated for you to save your
calibration data.
Restoring factory calibration
Using the KMM software, you can
easily restore the U2802A calibration
data from your settings to the original
factory settings.