Mach3 and VFD Wiring

**dcrowder** · 17-03-2016

Hi All,

Can anyone point me to some clear information (or offer me some) regarding wiring my VFD to the BOB for speed control with Mach3? I've got one of the HuanYang VFD's for a 2.2Kw spindle. The BoB is a DB25-1205.

I've seen relays mentioned but I've not found anything concrete yet.

Dave

**Clive S** · 17-03-2016

Originally Posted by dcrowder

Hi All,

Can anyone point me to some clear information (or offer me some) regarding wiring my VFD to the BOB for speed control with Mach3? I've got one of the HuanYang VFD's for a 2.2Kw spindle. The BoB is a DB25-1205.

I've seen relays mentioned but I've not found anything concrete yet.

Dave

I don't think the BOB has the capability to control the spindle speed or indeed has any relays on it.

**JAZZCNC** · 17-03-2016

Ok well there are two parts to this. Speed control and ON/OFF operation of the VFD.
On/OFF is easy enough and like you seen it's done using a Relay.

Controlling the speed needs 0-10v signal which is sent to the VFD.

Unfortunatly the DB25-1205 isn't much good for either of these.? It doesn't have 0-10v speed control and it doesn't have built in relay.
So this means you'll need separate Analog or PWM Speed control board which gives you 0-10V signal.

ON/OFF can be done using external Relay using one of the Outputs to control it. However you'll need to make sure the coil of relay used doesn't pull more current than the OUTPUT can provide. The BOB manual should tell you this Info.

Also be aware some external spindle boards will use up one of your Axis.

**dcrowder** · 18-03-2016

Originally Posted by JAZZCNC

Ok well there are two parts to this. Speed control and ON/OFF operation of the VFD.
On/OFF is easy enough and like you seen it's done using a Relay.

Controlling the speed needs 0-10v signal which is sent to the VFD.

Unfortunatly the DB25-1205 isn't much good for either of these.? It doesn't have 0-10v speed control and it doesn't have built in relay.
So this means you'll need separate Analog or PWM Speed control board which gives you 0-10V signal.

ON/OFF can be done using external Relay using one of the Outputs to control it. However you'll need to make sure the coil of relay used doesn't pull more current than the OUTPUT can provide. The BOB manual should tell you this Info.

Also be aware some external spindle boards will use up one of your Axis.

Did someone say BOB manual there?? :) er this is the DB25-1205 you know... low res connection diagrams showing only pin numbers are the order of the day here... but hey I'm on a budget!

This sounds as if it'd be more cost effective (in the long run) if I just go for a new BOB that'll do what I want. Does the Arduino solution work here? or are there any other budget solutions?

**JAZZCNC** · 18-03-2016

Originally Posted by dcrowder

Does the Arduino solution work here? or are there any other budget solutions?

Can't answer the Arduino question and terms Budget and CNC don't mix well. Experience taught me when mixed they =

**dcrowder** · 18-03-2016

Originally Posted by JAZZCNC

Can't answer the Arduino question and terms Budget and CNC don't mix well. Experience taught me when mixed they =

Ok most cost effective BOB then ;)

And do I take it that my work flow for today using what I have should be as such?...

Set Feeds in the GCode > Zero Machine then back off > Set spindle speed (lost here now as I was banking on mach3 looking after that) > Run Spindle > Run Gcode > Pray

**Clive S** · 19-03-2016

Originally Posted by dcrowder

Ok most cost effective BOB then ;)

And do I take it that my work flow for today using what I have should be as such?...

Set Feeds in the GCode > Zero Machine then back off > Set spindle speed (lost here now as I was banking on mach3 looking after that) > Run Spindle > Run Gcode > Pray

What is it exactly you want to know. If you are just starting out and you have a machine setup with the BOB you have. (and it works ok) You don't need to connect the VFD to the BOB to be able to run gcode.

**JAZZCNC** · 19-03-2016

Originally Posted by dcrowder

Ok most cost effective BOB then ;)

The most cost affective way for you at this moment given your limited CNC knowledge is forget Speed control from software. You'll hardly use it anyway and from what I'm reading having to Cam the spindle speed for each tool and material will cause you trouble at first while learning.

So the cheapest solution is buy Potentiometer and fit to VFD for easy manual speed control. Cost about £2 and fitted in minutes. Search the Forum and Clive S has explained how to do it and whats needed.

Then buy one of these and control the VFD ON/OFF using relay using Output from bob. Even the crapest Bob's will control this.

http://www.ebay.co.uk/itm/2-channel-...EAAOSwAYtWI-co

**cropwell** · 18-03-2016

Originally Posted by dcrowder

This sounds as if it'd be more cost effective (in the long run) if I just go for a new BOB that'll do what I want. Does the Arduino solution work here? or are there any other budget solutions?

There are plenty of cheap BoBs around with relays and speed control. The Arduino solution (whatever that is !) would probably cost you more than a new BoB.

Please enlighten me about what you mean - Arduino Solution.
Cheers
Rob

**dcrowder** · 18-03-2016

Originally Posted by cropwell

There are plenty of cheap BoBs around with relays and speed control. The Arduino solution (whatever that is !) would probably cost you more than a new BoB.

Please enlighten me about what you mean - Arduino Solution.
Cheers
Rob

maybe I'm just a little confused but I believe there are people using an arduino as a controller but they could easily be using a BoB also.