Selection of pulse train input (Pr. 291)
● Setting Pr. 291 "Pulse train I/O selection" = "1, 11, 21, 100" and Pr. 384 "Input pulse division scaling
factor" ≠ "0" changes the function of terminal JOG to a pulse train input so that the frequency can
be set to the inverter. In the initial setting, the JOG signal is assigned to terminal JOG. A maximum
pulse train of 100k pulses/s can be input.
● Connection with an open collector output system pulse generator
Pull up resistance
When the wiring length is long with open collector outputs, the influence of stray capacitance
causes the pulse to flatten out and prevents the input pulse from being recognized.
When the wiring length is long (10 m or longer of shielded twisted pair cable with a recommended
cable gauge of 0.75 mm²), connect the open collector output signal to the power supply by an
external pull-up resistance. The table below shows the reference resistance values for wiring
length. The stray capacitance of the wiring changes considerably according to how the cable is
laid, thus the above wiring lengths are not guaranteed values. When using a pull-up/down
resistance, check the permissible load of the resistor and the permissible load current of the output
transistor, and use within the permissible range.
Load current (reference)
Tab. 5-63: Resistance values for pull up and pull down resistances
● Connection with a complementary output system pulse generator
When pulse train input is selected, the function assigned to terminal JOG by Pr. 185 "JOG terminal
function selection" is invalid.
Pr. 291 is the selection parameter for pulse train output/FM output. Thus, before changing the set-
ting, check the specifications of the device connected to the terminal FM. (For the pulse train out-
put, refer to page 5-216.)
Pulse train input
Less than 10 m
Pulse generator output
(D) Operation command and frequency command
Pull down resistance
10 to 50 m
50 to 100 m
5 - 141