Hioki LR8410-20, Инструкция по эксплуатации

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Appendix 8 Concerning Noise Countermeasures
A
20
Insulation from noise sources

(temperature measurement by thermocouple)
The analog input channels are insulated from the chassis and each other.
Therefore, the measurement unit allows you to attach the thermocouple directly to a con-
ductor with a potential to measure it, provided that the voltage to ground does not exceed
the maximum rating. If noise is likely affect measurement, wrap heat-resistant tape
around the thermocouple for insulation, or use an ungrounded thermocouple and electri-
cally insulate the input line.
Setting the Digital Filter (valid for the LR8510, LR8511 and LR8515)
To remove noise from input signals, the digital filter can be set for the analog channels.
Select 50 Hz or 60 Hz to match the local line frequency.
See:
"3.9 Suppressing Noise (Enable Digital Filtering)" (p. 100)
Inserting a Capacitor in the Signal Line
When noise affects the signal source directly or when measuring high-frequency pulses,
it is effective to insert a capacitor between the "+" and "-" input terminals so that the noise
does not enter the 8430-20. When inserting a capacitor, use one with a rated voltage that
is equal to or exceeds the input voltage.
When a capacitor is inserted between the "+" and "-" input terminals, there are no restric-
tions on the recording interval because the filter is applied before the channel scan oper-
ation.
The capacitance of the capacitor should range from several

F to
several thousand

F. Insert the capacitor between the "+" and "-" in-
put terminals.
Thermocouple
Device being
Tested
measurement
unit