Need help wiring in a HY VFD to my machine...!

[12volt]

Hi all,

so I inherited a Bionica 8x4, 2.2kw spindle CNC router when I bought a business.. Its been working great guns for the last couple of years. Recently the VFD popped, I bought a new one, same model.

Matched the wiring, and we can get the spindle to turn on. All good so far.

But we can't get the attached Mach3 PC to alter the speed of the rpm. Which it could before. I've attached a photo that's of the original box wiring i took for reference.

The part that's confusing us...aside from it not working....is that all the googling we do, makes us think there should be at least a third wire going to the top line, and not just the blue 'n brown coming from the control board (which runs to a relay and effectively turns the unit on and off it seems) so we don't understand how MACH3 was able to control the spindle speed in this set up, and can't find any references to a set up like this to guide us.

Any help?

[Neale]

At a quick glance, there should be a couple of wires going to ACM and 0V, just on the right of the terminal block. You are quite correct - there is something missing!

You have Mach3 on a PC but how is the PC then connected to the rest of the machine? Likely to be either a simple break-out board connected to a PC parallel port, or a motion control board connected via USB or Ethernet. Knowing what that board is, would help a lot.

There is also an internal parameter setting on the VFD that decides whether the VFD speed is controlled by a control on the front panel or the external input. There might be some other parameters that need setting - there are some cheat-sheets around online that might help. Long time since I configured my own so can't remember what they all are!

[12volt]

At a quick glance, there should be a couple of wires going to ACM and 0V, just on the right of the terminal block. You are quite correct - there is something missing!

You have Mach3 on a PC but how is the PC then connected to the rest of the machine? Likely to be either a simple break-out board connected to a PC parallel port, or a motion control board connected via USB or Ethernet. Knowing what that board is, would help a lot.

images of the set up, all hooked into a usb into the board and out again. added some images of the mach3 set up too if that helps.

[Neale]

OK, couple more questions. Can you give us a picture of the output pins on the board so that we can read the labelling - if there is any. Or anything that suggests something like "analogue output" or similar. Just looking for clues here!

Also, in Mach3, one of the drop-down menus - "Plugin Control" - might have an entry which gives a clue about the type of USB board you are using. This is generally where any board-specific parameters are set up, but just knowing what the board is might help find some documentation on it.

Funny that the appropriate wires to the old VFD have disappeared, though.

[12volt]

OK, couple more questions. Can you give us a picture of the output pins on the board so that we can read the labelling - if there is any. Or anything that suggests something like "analogue output" or similar. Just looking for clues here!

Also, in Mach3, one of the drop-down menus - "Plugin Control" - might have an entry which gives a clue about the type of USB board you are using. This is generally where any board-specific parameters are set up, but just knowing what the board is might help find some documentation on it.

Funny that the appropriate wires to the old VFD have disappeared, though.

Pics added, can't see anything with that label unfortunately, as as you can see from plugin control, the only option is "video window" which is obviously not anything to do with this!

Those wires haven't disappeared as such, they never existed in the first place. I'm sure there must be a setting in the VFD that allows for the kind of control we are looking at, its simply that I don't know what it is...

[Neale]

Without a connection between the PC/Mach3/control board/VFD, it's difficult to see how the speed could ever have been controlled from software. There just ain't any obvious path by which it could be done. Not saying you are wrong, just can't see how it could have happened!

I see that you do have a knob on the front of the VFD. There is a parameter in the HY VFD to specify that you want front-panel speed control rather than via the control signal input. That might at least get you running after a fashion.

I can see that the board output connections are labelled but most are hidden under wiring. Is it possible to note what they are? I can see a couple with "S+" and "S-". Could be the terminals that we are looking for... My own next step would probably be to put a meter across those two and see what the output voltage is (if any) while changing the Mach3 spindle speed via the MDI. I would hope to see 0-10V, proportional to speed setting. But knowing how the rest of the terminals are marked would be useful - as would knowing what the board itself was!

[m_c]

As Neale says, without a connection, there is no way Mach 3 has been controlling the speed of the VFD.