Chapter 7 Usage of Various Functions
7-11
(6) RPM setting
- Can calculates RPM of input pulse
- RPM is stored in designated device.
- The RPM is expressed as:
cycle[ms]refresh rotateper Pulses
60,000Value)Last -Value(Current
RPM ×
×
=
(a) Examples of Program
- Refresh cycle : 1000ms, Pulses per rotate : 60, RPM save area : D0
Last value = 500(Assumption), Current value = 1000
RPM = { (1000 – 500) * 60,000} / {60 * 1000} = 500
Last value = 1000, Current value = 2000
RPM = { (2000 – 1000) * 60,000} / {60 * 1000} = 1000
Last value = 2000, Current value = 4000
RPM = { (4000 – 2000) * 60,000} / {60 * 1000} = 2000
1000ms 2000ms 3000ms
ⓐ 500 ⓑ 1000 ⓒ 2000
Current value
Time
In
p
ut
p
ulse
D0
,
D1
1000 2000 2001 4000