Hioki LR8432-20, Instruction Manual

Page: 68 / 238

3.4 Setting Configuration 2 – Input Channel Settings
60
[
°
C]
1000
400
0
-200
-1000
When the Thermocouple Measurement Range is Exceeded or
the Allowable Measurement Range of Each Range is Signifi-
cantly Exceeded
• Example: Using a type T thermocouple with range -200°C to
+400°C
When measurements are outside of the range of the thermocou-
ple, the waveform saturates and clings to the top of the screen as
shown at the right.
If the allowable measurement range of each range is significantly
exceeded, “OVER” or “-OVER” is displayed for the numerical val-
ue or cursor value and the calculated value or saved data is han-
dled as a full scale value.
Refer to “LR8432-20 Measurement Values” (p. A13).
About Burn Out Detection
Broken (disconnected) thermocouple wires are detected using a tiny (300 nA) sensing
current. The thermal equivalent of the thermoelectromotive force (thermocouple resis-
tance (
Ω
) times the 300 nA sensing current) is added to the measured value. However,
measurement errors can occur if the thermocouple wire is long or if the wire itself has a
large resistance, in which cases broken wire detection should be disabled (set to Off).