Hioki LR8410-20, Инструкция по эксплуатации

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3.3 Input Channel Settings
77
3
3
Chapt
er
3 Sett
ings
About Burn Out Detection
• When burn out detection is enabled, the instrument detects wiring breaks by outputting a minus-
cule current every recording interval during thermocouple measurement.?
• Since the detection process uses different timing than measurement, this operation does not
affect measured values.
• When using the same recording interval on the LR8510 or LR8511, the cutoff frequency when
burn out detection is enabled is higher than when the setting is disabled, reducing noise rejection
effectiveness.
See:
"Cut-off frequency" (p .290)
• When measuring the range's positive full-scale temperature, burn out detection may be triggered if
the thermocouple's resistance value exceeds the applicable value listed below. When you need to
string a long thermocouple for use with burn out detection enabled, take steps to avoid this phe-
nomenon, for example by using a thick wire diameter.
Reference: When measuring temperature close to the positive full-scale value in the K 100 C range
while using a thermocouple with a wire diameter of 0.32 mm, a wiring length of about 25
m or more may trigger burn out detection.
Range
100 ℃ f.s. 500 ℃ f.s. 1000 ℃ f.s. 2000 ℃ f.s.
thermo
couple
K 310 5400 960 2940
J 470 4150 － 200
E 450 5970 － 570
T 270 5440 5820 5440
N 270 1470 － 590
R 50 1040 － 580
S 50 120 － 1300
B － － － 350
W 220 910 － 250
Unit::

If Thermocouple Measurement Range is Exceeded, or If
the Range's Measurement Range Is Greatly Exceeded
• Example: Using a type T thermocouple with range -200 to +400°C

When measurements are outside of the range of the thermocouple,
the waveform saturates and clings to the top of the screen as
shown at the right.
• If the range's measurement range is greatly exceeded, the value
display and cursor value will indicate "OVER" or "-OVER," and cal-
culation values and save data will be replaced with a value from
the table below.
• When burn out detection is enabled, measurement results that fall
outside the thermocouple's measurement range or the range's
measurement range may be treated as a burn out event. (p. 76)
Input type Input range +OVER value -OVER value
thermocou
ple
100

C
327.67 -327.68
500

C
1638.4 -1638.4
1000

C
2000

C
3276.7 -3276.8
[  C]
1000
400
0
-200
-1000