In this tutorial we will explain how to use output board with VFD and spindle. We will describe how to set VFD* parameters and how to connect output board with VFD control inputs.

We are aware that many users use different VFD’s but no worries, the work flow in a sense should be the same.
*For purposes of this tutorial we will use MK3/4 controller and Chinese Huanyang VFD which is a well known piece of equipment among hobby machinists around the world.

Please follow this link to introduce yourself with output board and controller pin configuration:

Using output board with PlanetCNC controllers

Step 1: Configuring Huanyang VFD’s parameters

Variable Frequency Drive (VFD) drives an electric motor by varying the frequency and voltage supplied to the electric motor. VFD controls motors ON/OFF control,speed, direction etc..

All these functions can be controlled via external equipment (output board). Output board communicates with VFD trough its control inputs which are located on external terminal panel.

So first we need to define operating mode and configure VFD’s control inputs.

1.1: Defining VFD’s operating mode:

• We want to start/stop spindle from VFD’s external terminal panel

• We want to change motors direction from VFD’s external terminal panel

• We want to regulate motors RPM from VFD’s external terminal panel with 0-10 analog voltage signal

After going trough VFD’s user manual we know that we need to configure these parameters:

“Source of Run Commands” ->parameter PD001

PD001 → set it to value 1 (Set by external terminals)

Start, stop, change direction and speed can now be controlled via screw type input terminal.
“Source of Operating Frequency”-> parameter PD002

PD002 → set it to value 1 (Set by external terminals);

Source of operating frequency signal type is determined with parameter PD070

PD070 → set to value 0 (0-10V)

Motor speed can now be controlled via screw type terminal using the 0-10V input.

Step 2: Connecting output board with VFD

We need to connect output board with VFD control inputs.

Basic Connection Diagram :

Control inputs of VFD that we will use:

“FOR”: This input will be used for forward motor rotation

“REV”: This input will be used for reverse motor rotation

“DCM”: Common Terminal of Digital and Control Signals

“VI”: Analog Voltage Frequency Reference Input. 0-10V signal from output board will be connected to this input.

“ACM”: Common Terminal of Analog and Control Signals. GND signal from output board will be connected to this input.

Connect output pins of controller with input pins of output board:

Connect output board with VFD’s control inputs:

Wiring diagram below illustrates how relays and varying voltage output are connected with VFDs control inputs so that we achieve on/off, direction and speed control:

Short functional behaviour description:
When spindle is turned ON (M3 command), relay 1 is activated and motor rotates in forward direction(VFDs FOR input becomes active).

As soon as we change direction, relay 2 is activated and motor starts to rotate in reverse direction (VFDs REV input becomes active).

Please NOTE:

Before any wiring is done and equipment is connected, please check that all spindle, coolant and speed g-codes activate correct corresponding relays and outputs.

Connect SD card adapter with the Planet-CNC controller:

Mk3 and Mk3/4 controller:
SD card adapter is connected to Mk3 and Mk3/4 controller with 10pin flat cable trough SD&I2C connector.

Mk2 controller:
SD card adapter is connected to Mk2 controller with 10pin flat cable trough EXT connector.

Export your toolpath to Raw file format in CNCUSB controller software: “File/Export Toolpath to Raw”:

Raw file must be named “toolpath.raw” and must be located on SD cards root folder.

Program Execution:

You can start the execution of your program from SD card:
“Machine/Start from SD card”

If you do not intend to use computer, you can connect a switch to desired input, assigned it as “Start” switch in software and start the execution of the program without the use of computer.

In settings you set input as ‘Start’ switch:

Mk3 and Mk3/4:
File/Settings/Input

Mk2:
File/Settings/Input/Use Start

NOTES:

When running your program from SD card, the initial starting point of machining is always machines absolute XY=0 position.

It is important that the version of controller(Mk2, Mk3..) connected to computer when you export your toolpath to RAW format is the same as the one that will be later executing program from SD card adapter.

When you use controller in standalone option (no computer and no power supply via USB) it is necessary to use external power supply. Normal 8-24VDC adapter is suitable.

Mk2 requires jumper “JMP” to be short circuited (soldered) while Mk3 and Mk3/4 do not need this jumper to be short circuited.

Same settings need to be used when exporting toolpath(RAW file) and when updating controllers firmware (same settings need to be loaded into software).

In spirit of Easter holidays(with a slight delay) we decided to wipe the dust from our EggBot and see if still works. We thought that it would be perfect if we use Toslink devices to demonstrate how both, Mk3 controller and Toslink work perfectly hand in hand.

For better understanding of Toslink please follow link below:

http://irnas.eu/goodenoughcnc/2016/03/10/toslink-cnc

Toslink can be integrated with a small stepper driver by just being stacked with motor driver and connected via flat ribbon cable:

Master Toslink board sends coded optical signal to all Toslink slave devices:

Controller is connected with Toslink master board which is connected with Toslink devices via optic fibre cable:

Here is a short video showing Mk3 controller, Toslink and EggBot in action.