Denford VMC1300 - Rescued

[Clive S]

Does that board isolate the PWM in from the 0-10V output?

This morning I checked the voltage between 0-10V and earth about 200V and between PWM and earth 1.5V so it isolates the two.

[m_c]

This morning I checked the voltage between PWM and earth about 200V and between 0-10v and earth 1.5V so it isolates the two.

Good to know.
Although I assume you meant to have those two voltages the opposite way around? ;-)

[Clive S]

Good to know.
Although I assume you meant to have those two voltages the opposite way around? ;-)

Well spotted. I have edited mine would you mind editing to save confusion for others.

[Chas Ixion]

Just a quick update. Got a scope on the 0-10v spindle speed output from the RMHV and its analogue and not PWM.

The manual seems to suggest that it is possible to configure the unit to output PWM but I can not find anything in the manual to show me how.

[GND]

I'm in the process of planning the conversion of my recently acquired Novamill, and came across this during my research - https://www.summet.com/blog/2016/01/...-speed-control. It shows how to tap into the existing spindle drive isolation circuit with your own PWM signal, thus saving any new circuits or power supplies. In my case I'm just replacing the top controller board, and replacing it with a modern motion controller - but keeping the lower board and the stepper drivers - so this should work for me. Sounds like you may be replacing more of the electronics, so it may not be appropriate. But hopefully this is useful info for others reading the thread.

Cheers
Graeme

[Clive S]

If this helps you can get the connector here https://uk.rs-online.com/web/p/produ...B&gclsrc=aw.ds

I started doing this and changed my mind and threw the boards out. As you can see in post #28. unfortunately I also threw the connector out otherwise you could of had it.

Good luck with the conversion.

[GND]

Thanks for that, Clive. I'm just finalising my choice which motion controller to use. Too many choices! However my current plan is to make a kind of motherboard with one of those 96-way connectors on it, that replaces the existing top board. The motion controller will then sit on this. I can then provide any BoB type functions on my mini-motherboard - like voltage level shifts or opto isolation. Feels like quite a neat way to tackle the problem, but time will tell. As you say, we sometimes start with a plan and then throw it all away and do it differently!!

Just out of interest, what electronics did you use? I can see a BoB on your photo, and maybe a couple of stepper drives? But not anything I could identify....

All the best
Graeme