Omega RD-MV100 Series, Руководство пользователя

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5-16
4. Burnout
Select from [Off], [Up], and [Down].
Off : Disable the burnout function.
Up : When the thermocouple burns out, the measured result is set to
positive over range “+ .”
Down : When the thermocouple burns out, the measured result is set to
negative over range “+ ”.
5. RJC
Set [External] or [Internal].
External : Use the external RJC.
Internal : Use the RJC of the recorder.
6. Volt (
µ
V)
If [External] is selected, set the reference junction compensation voltage to add
to the input.
Pressing the [Input] soft key displays a window used to enter the voltage. Enter
a value (–20000
µ
V to 20000
µ
V, initial value is 0
µ
V) and press the DISP/
ENTER key. For the procedures related to entering numerical values, see
“Entering Numbers” on page 3-21.
Confirming operation
To confirm the new settings, press the DISP/ENTER key.
To cancel the new settings, press the ESC key. A window appears for you to confirm the
cancellation. Select [Yes] using the arrow keys and press the DISP/ENTER key.
Explanation
The integration time of the input A/D converter
The recorder uses an A/D converter to convert the input signal to a digital signal. The A/
D converter operates at an integral time of 16.7 ms (60 Hz), 20 ms (50 Hz), or 100 ms.
By setting the integration time to match the frequency of the power supply being used,
power supply frequency noise can be minimized.
Burnout of thermocouple input
When the alarm is set to detect positive or negative over range, the occurrence of
burnout of thermocouple can be displayed as an alarm.
Turn the burnout function OFF when connecting the input wires in parallel with other
devices.
Reference junction compensation of thermocouple input
When using the reference junction compensation of the RD-MV100, see “Precautions to
be taken while wiring” in section 2.3, “Input Signal Wiring.”
When using the external reference junction compensation, set an appropriate reference
junction compensation voltage. As in the example in the following figure, if the reference
junction temperature for the external reference junction compensation is T
0
°
C, set the
thermoelectromotive force of the 0
°
C reference for T0
°
C as the reference junction
compensation voltage.
An example of External reference junction compensation
External reference junction compensation
(Maintain the junction between the
thermocouple and the copper wire at T
0
°
C)
Thermocouple
Copper wire
RD-MV100
5.9 Setting the A/D Integration Time, Scan Interval, Burnout, and Reference Junction Compensation (Basic
Setting Mode)