Mitsubishi Electric FR-A800, Instruction Manual

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Parameters (D) Operation command and frequency command
FR-A800 5 - 285
Speed synchronized operation by pulse input/output
When the wiring length between FM and JOG is long, 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 size of
0.75 mm
2
), connect the terminal JOG to the terminal PC 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 permis-
sible load current (terminal PC: 100 mA, high-speed pulse train output: 85 mA), and use within the
permissible range.
●
Setting "100" to Pr. 291 enables out of the pulse train input as it is to the pulse train output (terminal
FM). Connecting in a daisy chain enables speed synchronized operation of multiple inverters.
●
Set Pr. 384 to "125" for inverters that receive pulse train since the maximum pulse train output is
50k pulses/s.
●
The maximum number of input pulses should be 50k pulses/s.
●
When performing synchronized operation, wire according to the following procedure. (This is to
prevent contact input of 24 V from being applied to the terminal FM.)
Set pulse train output (setting other than "0, 1") to Pr. 291 on the master side inverter.
Turn the inverter power supply OFF.
Wire the slave side terminal JOG-SD to the master side terminal FM-SD.
#
Turn the inverter power supply ON.
I002763E
Fig. 5-116: Speed synchronization
Wiring length Less than 10 m 10 to 50 m 50 to 100 m
Pull-up resistance Not required 1 kΩ 470 Ω
Load current (reference) 10 mA 35 mA 65 mA
Tab. 5-115: Resistance values for pull up and pull down resistances
NOTES After changing the Pr. 291 setting, connect the JOG terminal to the terminal FM-SD. When FM out-
put (voltage output) is taken as the pulse train, take caution to prevent voltage from being applied
to the terminal FM.
Use the sink logic (factory setting) for the slave side inverter. The inverter does not operate prop-
erly with source logic.
To next inverter (slave)
JOG
JOG FM
SD SD
Pull up
resistance
Inverter (master)
Speed
command
Pulse train
output
PC
Pulse train
input
Pulse train
output
Speed
command
To next inverter (slave)
SD
FM