Mitsubishi Electric FR-A7AL Instruction Manual page 82

ENCODER PULSE DIVIDING OUTPUT
CAUTION
For open collector output, the signal may become unstable if the input resistance of the connected device is
large and the device may detect the signal incorrectly. In this case, adding a pull-up resistance as shown
below will improve the phenomenon.
Select a pull-up resistance in consideration of the input current of the connected device so that the open
collector output current will not exceed the output permissible load current.
Inverter
FR-A7AL
76
Pull-up resistance
FPA2/FPB2/FPZ2
SD
Power supply
- +
Connected device