Yokogawa Removable Chassis DX1000N - Manual (Page 22)

3-8
SM 04L41B01-01E
3.4 Test Procedures
Reference Junction Compensation Accuracy
● Test Procedures
Measure 0°C on all channels, and check that the display is within the reference values
below.
Set all channels to thermocouple type T.
Reference value: ±0.5°C
Calibrated thermocouple wires
0°C standard temperature device
(Model: ZC114 from Coper Electronics Co., Ltd.
or equivalent)
+/A
–/B
Input terminals
• Use a calibrated thermocouple, and wires of 0.5 diameter or less without terminal
tips. Also, be sure to take the level of thermocouple error into consideration during
testing.
• Monitor the 0°C standard temperature device at all times, and confirm that it is
within 0°C ±0.05°C.
• When using a 0°C standard temperature device, ensure that the tip of the
thermocouple floats about 10 mm off the bottom.
• Perform the test in a stable environment. If drafts are present and may influence
the results, position the equipment to avoid them.
• After connecting the thermocouple, allow a warm-up time of 30 minutes or more
before begging measurement.
• Always use terminal covers.
• If the quality is found to be sufficiently stable, perform a test on one representative
channel for each AD converter*.
* Choose any channel number for each A/D from those listed in the “A/D Converter
Configuration” in section 3.4, “Measurement Accuracy.”
Ex.: With the DX1004, set channels 1 and 3 as representative channels.
• Raise the DX at least 20 mm off the surface (stand) where it is positioned, and
place nothing under the terminal block.
Stand
20 mm or more
Nothing under the terminal block
Battery Backup
● Test Procedures
1. Set the date and time. Also, set an arbitrary channel to the 20 mV range.
2. Turn OFF* the power switch.
* The DX1000N power supply switch is located inside the bezel. Disconnect then
reconnect the power supply, or open the bezel and operate the power supply switch (see
section 7.3).
3. Turn ON the power after approximately one minute, then check that the set date,
time, and range are not initialized.