docs:blackbox-x32:connect-vfd

3.3.5 BlackBox X32 0-10v Analog Output

OpenBuilds BlackBox includes a 0-10v Analog Signal Voltage output that can be used to control spindles/other toolheads that need a 0-10v signal to run.

NB Note this is a low level logic Signal voltage, it should not be used to drive anything directly. This signal should be connected to an external drive system, for example a VFD or a DC Spindle Controller. If you need help, head over to our Forums to ask about specific devices and how to connect them

  • To use the signal, connect between the GND and 0-10v pins on the 0-10v plug as shown.
  • To Activate the signal, send an M3 Sxxx where X=0-1000 (1000 = default Grbl configuration, or send S=what you have set for $30 - Max spindle speed, RPM). For example, to have a 10v output send M3 S1000, to have a 5v output send M3 S500, to have a 1v output send M3 S100 etc. (NB scale accordingly if your $30 is not '1000')
  • If you want to use this feature to control Spindle RPM (on supported spindles), please read https://github.com/gnea/grbl/wiki/Grbl-v1.1-Configuration#30---max-spindle-speed-rpm

Calibrate output voltage

TIP: You may need to fine tune the output to be exactly 10v:

  1. Send an M3 S1000 to the controller (1000 = default Grbl configuration, or send S=what you have set for $30 - Max spindle speed, RPM)
  2. Measure the voltage between GND and the 0-10v Terminal
  3. Use a small flat head screwdriver to adjust the 0-10v Fine Tuning Adjustment until the output is exactly 10.0v

This will ensure that command Spindle RPM is as close to the actual as possible

Generic VFD wiring instructions:

This example uses RELAY1 as the Tool Enable, RELAY2 as FWD/REV and the 0-10V Output as speed CONTROL to control the VFD's activation, direction and speed respectively.

Every VFD brand labels their inputs slightly differently, and they all have different parameters to essentially set up the same features, but as can be seen from the diagram above, and cross referencing your VFD manual, you should also be able to adapt to other VFDs as well - almost all VFDs accept a dry contact enable/fwd/rev signal, and analog voltage 0-10v speed signal.

Checkout our Forums for more information:

The following are community-provided writeups for wiring popular VFDs to BlackBox

VFDLink
Huanyang VFD https://openbuilds.com/threads/vfd-spindle-control-via-openbuilds-blackbox-controller-and-software.15167/ - NOTE writeup is for the older BlackBox 4X - just adapt to new terminal position on BlackBox X32
YL620-A VFD https://openbuilds.com/threads/yl620-a-vfd-settings.15780/ - NOTE writeup is for the older BlackBox 4X - just adapt to new terminal position on BlackBox X32
A2-8015 VFD https://openbuilds.com/threads/a2-8015-vfd-inverter-with-1-5kw-air-cooled-spindle.19447/ - NOTE writeup is for the older BlackBox 4X - just adapt to new terminal position on BlackBox X32
H100 VFD https://openbuilds.com/threads/h100-vfd-220v-with-1-5kw-spindel-2-poles-air-cooled-with-black-box.19442/ - NOTE writeup is for the older BlackBox 4X - just adapt to new terminal position on BlackBox X32 and wire the Direction terminals via the Relays instead of direct GPIO
docs/blackbox-x32/connect-vfd.txt · Last modified: 2025/04/30 13:53 by admin