Hioki LR8432-20, Инструкция по эксплуатации

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3.4 Setting Configuration 2 – Input Channel Settings
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Set
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easurement
Revolution Measurement Theory
Pulse count is measured using the instrument’s
internal 10 ms sampling interval.
The revolution rate (r) per second during time t
s
is obtained
by dividing the number of pulses from (t-1) to t
s
by the num-
ber of pulses per revolution.
Example: Pulses per revolution = 4
When the number of pulses counted in one second is
P
100
= 1000 c,
and the number of pulses counted in two seconds is P
200
= 2000 c,
then the revolution rate (r/s) at t=2s (r
t=2
) can be obtained.
When time t
s
is less than one second
The pulse count at (t –1)
s
(whole seconds) cannot measured, so 100 times the pulse count
between (t -0.01)
s
and t
s
serves and the pulse count for one second to obtain the revolution
rate.
As a result, revolution measurements when t is less than one second are scattered.
If the allowable measurement range of each range is significantly exceeded,
“OVER” or “-OVER” is displayed for the numerical value or cursor value and
the calculated value or saved data is handled as a full scale value.
Refer to “LR8432-20 Measurement Values” (p. A13).
0 10 ms 20 ms 1 s 2 s
Pulse Count
P200 P100 P2 P1 0
Pulses per revolution
Pulse count at t
s
minus pulse count at (t -1)
s
r [r/s] =
(r/s: Revolutions per second)
r
t=2
=
4
2000
−
1000
= 250 [r/s]
Pulses per revolution
Pulse count at t
s
minus pulse count at (t -0.01)
s
r [r/s] = x 100