This is a userspace HAL program, written in python, to control VFD’s from Mitsubishi.
Specifcally the A500 F500 E500 A500 D700 E700 F700 series - others may work.
mitsub_vfd supports serial control using the RS485 protocol.
Conversion from USB or serial port to RS485 requires special hardware.

Since this is a userspace program it can be affected by computer loading and latency. It is possible to lose control of the VFDs. It is optional to set the VFD to stop if it loses communication if that is desirable. One should always have an Estop circuit that kills the power to the unit in case of emergency.

This component is loaded using the halcmd "loadusr" command:

loadusr -Wn coolant mitsub_vfd spindle=02 coolant=01

The above command says:
loadusr, wait for coolant pins to be ready, component mitsub_vfd, with 2 slaves named spindle (slave #2) and coolant (slave #1)

1. Command Line Options

The command line options are:

  • -b or --baud <rate> : set the baud rate - all networked VFDs must be the same

  • -p or --port <device path> : sets the port to use such as /dev/ttyUSB0

  • <name>=<slave#> : sets the HAL component/pin name and slave number.

Debugging can be toggled by setting the debug pin true.

Turning on debugging will result in a flood of text in the terminal.

2. Pins

Where <n> is mitsub_vfd or the name given during loading.

  • <n>.fwd (bit, in) True sets motion forward, False sets reverse.

  • <n>.run (bit, in) True sets the VFD in motion based on the .fwd pin.

  • <n>.debug (bit, in) Prints debug info to the terminal.

  • <n>.alarm (bit, out) signals an alarm state of VFD.

  • <n>.up-to-speed (bit, out) when drive is at commanded speed (speed-tolerance is set on vfd)

  • <n>.monitor (bit, in) some models (eg E500) cannot monitor status -set the monitor pin to false in this case pins such as up-to-speed, amps, alarm and status bits are not updated.

  • <n>.motor-cmd (float, in) commanded speed to the VFD (scaled to hertz by default).

  • <n>.motor-fb (float, out) feedback speed from the VFD (scaled to hertz by default).

  • <n>.motor-amps (float, out) Current amperage output of motor.

  • <n>.motor-power (float, out) Current power output of motor.

  • <n>.scale-cmd (float, in) Scales the motor-cmd pin to arbitrary units. default 1 = Hertz.

  • <n>.scale-fb (float, in) Scales the motor-fb pin to arbitrary units. default 1 = Hertz.

  • <n>.scale-amps (float, in) Scales the motor-amps pin to arbitrary units. default 1 = amps.

  • <n>.scale-power (float, in) Scales the motor-power pin to arbitrary units. default 1 = .

  • <n>.estop (bit, in) puts the VFD into emergency-stopped status.

  • <n>.status-bit-N (bit, out) N = 0 to 7, Status bits are user configurable on the VFD. bit 3 should be set to at speed and bit 7 should be set to alarm. others are free to be set as required.

3. HAL example

# example usage of the Mitsubishi VFD driver
loadusr -Wn coolant mitsub_vfd spindle=02 coolant=01

# **************** Spindle VFD setup slave 2 *********************
net spindle-vel-cmd               spindle.motor-cmd
net spindle-cw                    spindle.fwd
net spindle-on          
net spindle-at-speed              spindle.up-to-speed
net estop-out                     spindle.estop
#       cmd scaled to RPM
setp spindle.scale-cmd .135
#       feedback is in rpm
setp spindle.scale-fb 7.411
#       allows us to see status
setp spindle.monitor 1

net spindle-speed-indicator spindle.motor-fb        gladevcp.spindle-speed

# *************** Coolant vfd setup slave 3 ***********************
net coolant-flood     
net coolant-is-on               coolant.up-to-speed   gladevcp.coolant-on-led
net estop-out                   coolant.estop
#       cmd and feedback scaled to hertz
setp coolant.scale-cmd 1
setp coolant.scale-fb 1
#       command full speed
setp coolant.motor-cmd 60
#       allows us to see status
setp coolant.monitor 1

4. Configuring the Mitsubishi VFD for serial usage

4.1. Connecting the Serial Port

The Mitsubishi VFDs have an RJ-45 jack for serial communication.
Since they use RS485 protocol, they can be networked together point to point.
This driver was tested using the Opto22 AC7A to convert from RS232 to RS485.

4.2. Modbus setup

Referenced manuals:

communication option reference manual and A500 technical manual for 500 series.
Fr-A700 F700 E700 D700 technical manual for the 700 series

The VFD must have PR settings adjusted manually for serial communication.
One must power cycle the VFD for some of these to register eg PR 79

  • PR 77 set to 1 -to unlock other PR modification.

  • PR 79 set to 1 or 0 -for communication thru serial.

  • PR 117 set to 0-31 -slave number, driver must reference same number.

  • PR 118 tested with 96 -baud rate (can be set to 48,96,192) if driver is also set.

  • PR 119 set to 0 -stop bit/data length (8 bits, two stop)

  • PR 120 set to 0 -no parity

  • PR 121 set to 1-10 -if 10 (maximuim) COM errors then VFD faults.

  • PR 122 tested with 9999 -if communication is lost VFD will not error.

  • PR 123 set to 9999 -no wait time is added to the serial data frame.

  • PR 124 set to 0 -no carriage return at end of line.