Example Of Calculating Conversion Factor - Omron CP1L-EL20DR-D Operation Manual

Inverter Positioning
Example of
Calculating
Conversion Factor
332
(2) The encoder resolution times the counter multiplier times the gear ratio
equals the number of pulses output by the encoder for one motor shaft
revolution.
CP1L-EL/EM
Pulse output
instruction
Target frequency
Conditions
• Frequency for 1 revolution/s for inductive motor: 2 Hz (motor specification)
• Rotary encoder resolution: 1,000 pulses/revolution (encoder specifica-
tion)
• High-speed counter multiplier: x4 (PLC Setup)
• Gear ratio between motor and encoder shafts: 1/4 (machine specification)
Calculations
The factor goes into the formula as shown below.
Frequency of 1000 × 4 × 1/4
internal pulse
output (Hz)
500 × Power supply frequency to motor (Hz)
For example, to output a power supply frequency of 10 Hz to the motor:
Frequency of internal pulse output = 500 × 10 Hz = 5,000 Hz = 5 kHz
Therefore, set a pulse output frequency of 5 kHz in the pulse output instruc-
tions (e.g., PLS2).
Internal
pulses
Error
counter
Conversion formula
Power supply
frequency to
2
motor (Hz)
Section 7-3
Inverter
Motor
Power
supply
frequency
Encoder