Omron K3HB-C User Manual page 73

Section 5 Functions and Operations
■ F4: Rotational Difference
5-12
Measuring the Rpm/Circumferential Speed Difference (Absolute
Difference) between Two Conveyors
Operation Configuration (Application)
• Basic Operation
The difference between the speed of input A and the speed of
input B is displayed.
The measurement value can be obtained using the following
formula:
D = fb 60 fa
fa: Frequency A (Hz)
: Prescale value A
D: Measurement value
Example:
This example shows the prescale values and the prescale set
values for displaying the difference between speeds using two
rotary encoders, each of which outputs 60 pulses per rotation.
Prescale value of Input A ( ) = 1/60 = 0.01666 ...
Prescale value of Input B ( ) = 1/60 = 0.01666 ...
Prescale value of Input A, X (mantissa): ps. ax = 1. 6666
Prescale value of Input A, Y (exponent): ps. ay = 10 -2
Prescale value of Input B, X (mantissa): ps. bx = 1. 6666
Prescale value of Input B, Y (exponent): ps. by = 10 -2
Encoder
HH
H
PASS
L
LL
Alarm outputs
60
fb: Frequency B (Hz)
: Prescale value B
2
1.6666 10
2
1.6666 10