Hioki 3801-50, Instruction Manual

Page: 34 / 94

30
2.9 DUTY Ratio Measurement
The duty ratio is the ratio between the pulse width and the
pulse cycle. This instrument displays this ratio in terms of
100 (%).
Plus slope duty ratio (D+): D+ = tw
+
/T × 100 (%)
Minus slope duty ratio (D-): D- = tw
−
/T × 100 (%)
2.9 DUTY Ratio Measurement
T
t
Plus slope pulse width Minus slope pulse width
Pulse cycle (=tw
+
+ tw
-
)
0 V
tw
-
tw
+
The bar graph conforms with voltage measurement or
current measurement.
1.
Set the function switch.
❖
See Section 2.2 Voltage Measurement
(page 19)
❖
See Section 2.3 Current Measurement
(page 21)
❖
See Section 2.8.2 Frequency Counter Mea-
surement (page 29)
2.
Use the
SHIFT
key to select either
DC, AC, or AC+DC.
Otherwise, select the Hz counter
(one cycle).
3.
Use the
Hz
key to select the DUTY
ratio.
4.
Connect the test leads to the test ter-
minals.
5.
Read the value displayed in the
main display.
To switch the pulse slope polarity ,
hold down the
SHIFT
key.
Duty ratio cannot be measured if the Hz
counter (100 cycles) is selected.
SHIFT
AC DC
AC+DC
Hz
<Example>
When measuring AC voltage
( % lights)