Hioki 3290-10, Instruction Manual

Page: 95 / 152

5.1 Auto Zero Adjustment Function
89
1
2
3
4
5
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7
8
9
10
5
A
ppl
ic
a
b
le
M
easurement
M
o
d
e
s
Measurement Modes: DC and AC+DC
The auto-zero adjustment function automatically adjusts the offset
in the internal circuit that results from temperature characteristics
or clamp-sensor magnetization. The clamp core is magnetized
when a large DC current is measured or a powerful magnet is
placed close to the clamp core.
1.
Close the clamp-on sensor tightly.
2.
Verify that the display is stable with no signal applied.
3.
Press
SHIFT
→
(
0ADJ
) to execute auto zero adjustment.
4.
appears when finished.
Applicable Measurement
Modes
5
5.1 Auto Zero Adjustment Function
Before Adjustment
Finished
• Because the zero suppression function may be enabled (forc-
ing counts of five or less to display as zero), perform auto zero
adjustment even if the displayed value is zero.
• The maximum adjustment ranges in current measurement
mode are as follows:
L range: approx. ± 450 dgt., H range: approx. ± 45 dgt.
Auto zero adjustment cannot be performed if the displayed
value is outside of these ranges.
• If auto-zero adjustment is performed during current measure-
ment or while the reading fluctuates, zero adjustment may not
be performed correctly.
• When AUTO ranging is enabled, auto zero adjustment is per-
formed in both L and H ranges.
• See "Sensor Temperature Characteristics" (page 58) for the
temperature characteristics of the clamp-on sensors.