Can you get DC VFD's?

[hotponyshoes]

I have a small 230v dc motor.
Can I get a vfd to run it from a regular single phase 230v ac supply?
Or, another easy-to-set-up solution?

 

[Pete.]

Yep. Parker Eurotherm drive or something similar.

Eurotherm SSD 512/08 DC Drive | eBay

Supplied used in very good condition.

www.ebay.co.uk

That's a 8 amp 2 quadrant drive with field supply. Exactly what I use on my Monarch lathe except mine is 16 amp.

 

[Kram]

You can get controllers but they are not VFD's. I have one spare along with the 1.2kw dc motor from the lathe.

 

[daleyd]

Yeah you can buy Dc motor controllers - they can range from really cheap things on a circuit board with a pot on the front to ones that look just like a vfd with all sorts of inputs and outputs. Depends what you want and how much you want to spend.

 

[m_c]

SCR drives are quite common, and come in various configurations.

If you want a known brand, a KB Electronics KBIC are reasonably priced, but the standard drives have non-isolated controls (the control circuitry sits at around half mains voltage).
More expensive, but fully enclosed, I'd probably look at a Sprint drive, which come in non-isolated and isolated versions.

Off course, it all depends on what you'd like to achieve. If you want accurate speed control, KBIC use a basic load resistor to compensate for load.
IIRC Sprint drives will also do basic load compensation, but also have the option of accepting a tacho feed.

There is also the option of a cheap SCR drive from whatever your choice of Chinese goods site is, but they're likely to only offer quite crude control.

 

[Maker]

A PWM one will be better than an SCR, more torque, particularly at lower speeds.

 

[Turbo]

Interested in this thread as I've a large DC motor from a treadmill but no way to control it (the treadmill controls are goosed).

 

[hotponyshoes]

To be honest, I don't really know exactly what I am after.
I have a high quality motor with mountings, gearbox etc..
It looks like it would be perfect for some sort of project (welding rotator or something?) if I can find a way of controlling the speed of it.

If I spent the time building something around it then I would want a quality controller that's going to last (or be easy & cheap to replace) but at the same time I don't want to pay more for a controller than the sort of money I could buy another 'more common' motor and controller combo for if you see what I mean!

The specs of this motor are
230v dc
400w
2.5a
6500 rpm.

I have seen plenty of cheap chinese speed controllers but they only seem to go up to 40v or so.
At the same time, the eurotherm thing linked to above looks good but I don't need the 8a capability. Something like that at less amps and a lower price would be ideal!

 

[Pete.]

Gearing a 6000rpm motor down to welding position speeds is going to be a challenge.

 

[hotponyshoes]

Gearing a 6000rpm motor down to welding position speeds is going to be a challenge.

I have a gearbox for it. In fact I have a couple that could be stacked if required plus a box of other pulleys and stuff.

It's only because I already have it and have a load of bits that I can play with that I am looking for a drive for it!

I might find something more suitable to use it for yet..