Omron CP1H-CPU - 05-2006 Operation Manual page 278

Pulse Outputs
Procedure
Restrictions
Precautions when
using the Pulse
Output Function
Pulse Output System
Make the following settings in the PLC Setup.
Pulse Output 0 to 3
Speed Curve Trapezium
S-shaped
The following restrictions apply when using S-curve acceleration/deceleration.
Starting Frequency
The starting frequency must be 100 Hz or greater. If the starting frequency is
set to less than 100 Hz, it will automatically be increased to 100 Hz if S-curve
acceleration/deceleration is set.
Pulse frequency
Automatically
increased
to 100 Hz.
100 Hz
50 Hz
Target Frequency
S-curve acceleration/deceleration will not be performed if the target frequency
is less than 100 Hz.
Pulse frequency
50 Hz
No
acceleration/deceleration
The CP1H CPU Unit's pulse output frequency is determined by dividing the
source clock frequency by an integer ratio. (The source clock frequency for
ports 0 and 1 is 20 MHz and the frequency for ports 2 and 3 is 16.4 MHz.)
Consequently, there may be a slight difference between the set frequency and
the actual frequency, and that difference increases as the frequency
increases. The actual frequency can be calculated from the following equa-
tions.
Integer dividing ratio calculated
from user's set frequency
16.4 or
Source
20 MHz
Frequency
clock
divider
When a pulse output is executed with accelera-
tion/deceleration, this setting determines
whether the acceleration/deceleration rate is lin-
ear (trapezium) or S-shaped.
Time
Time
Output pulses (actual frequency)
Section 5-3
247