Forecasted Cycle Calculations - Omron K3HB-C User Manual

Appendices

Forecasted Cycle Calculations

Forecasted Cycle Calculation
Input pulse
Frequency
A-30
When the input pulse stops suddenly, forecasted cycle calculations are
used to wait for the next input pulse based on frequency forecasts.
During forecasted cycle calculations, the frequency is forecasted
continuously for any point in time regardless of when the next input
pulse is received. This increases the response characteristic in the
shaded portion of the diagram.
T T
1 2
P P P
0 1 2
1/T
1/T
1
0
(1) Frequency calculation is not possible with only pulse P
calculated value remains at 0.
(2) When pulse P
1
so the frequency can be calculated as 1/T
(3) If pulse P is received and T
2
the frequency has increased), so 1/T
that point.
(4) If time T expires before the next pulse is received after receiving
2
pulse P , it is clear that the frequency will be lower than 1/T
2
the value will not be know until the next pulse is actually received.
(5) If time T expires and the next pulse still has not been received
2
after receiving pulse P
for any point in time. The forecasted value if time T
from receiving pulse P
time, the frequency will be 1/T
been forecasted accurately.
(6) The response characteristic for rapid changes in the input
frequency is thus improved, in comparison to assuming that the
frequency is 1/T
Forecasted cycle calculation
T
3
T
2
P
3
2
1/T
Forecasted
cycle calculation
is received, the time T , from P
1
> T , the cycle has shortened (i.e.,
1 2
is used as the frequency at
2
, the frequency is forecasted continuously
2
is 1/T . If P is actually received at that
2 3 3
, i.e., the frequency at that time has
3
until pulse P is received.
2 3
Time
3
, so the
0
to P is the cycle,
0 1
.
1
, but
2
has expired
3