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Phase converter / inverter

Boggled as to how to do this.

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Mark C27/10/2015 21:36:21
707 forum posts
1 photos

Jon, that list is pretty much standard on all drives these days. Steve Pavey can help along with plenty of others but I think his conversion was the first time he has done one and his was not the easiest as he went the DIY motor conversion route.


Clive Foster27/10/2015 21:58:51
2152 forum posts
73 photos

Having done the static converter, rotary converter, individual machine inverter and currently Drives Direct Plug'n Play whole shop inverter with smoothing coils on the output I can reasonably claim some relevant experience. If the electrician finally gets off his tail I should have utility 3 phase hooked up by Christmas, more like £5,000 than £500 to install plus trenching & groundworks tho'. Guess that will be a full set.

Static capacitor type converters at one per motor work pretty well when tuned in but over 1 1/2 hp can be problematic. I've built several but a proper, safe, plug'n play design with built in NVR and automatic switching out of the start boost capacitor is too expensive these days and often a bit touchy to tune. So you need a stock of capacitors. Done right its very effective. Only one I'd still do was a system like the one I fitted to my old Pollard Corona drill. Run cap permanently on the motor. Pollard built start button with monster contacts handles the start boost capacitor just fine. Hold the button down for a one-two count and up to speed.

Motorrun brand static converter with step up transformer worked OK to run the Bridgeport but needed capacitor switching according to load and always buzzed. Could have handled more machines if I had them but switching would have been a pain. Converting to a rotary version with a 5 HP motor on the back killed the switch fiddling but buzz was much worse. Especially after I put it on a shelf and set the whole shop going! Friend Mike has a Transwave set-up for his shop which is a building in a building type inside a steel panelled barn. Transwave lives in the barn 'cos its too noisy in the shop. Not noisy noisy but more than irritating. Had some issues with starters due to poor voltage regulation on start-up. Motor dragging the generated phase down but we eventually sorted that.

Single inverter per machine works as it says on the tin but costs do add up when you get more kit. I'm up to twelve three phase machines now. The shaper is still on its own inverter. Although the Eillot 10M has a good range of gearbox speeds I like the extra control and low speed start up.

10 HP plug'n play inverter from Drives Direct just works like utility power should. Zero futzing about although I'd always advocate the output smoothing coils even though it adds around 50% to the price. Unless you are certain you only need one or two machines thats the way I'd go despite the higher cost over one or two individual inverters. Much to be said for do it once do it right. I shudder to think of how much time I've spent over the years fiddling to get stuff going. Admittedly in days of yore fiddling and affordability went hand in hand. Building static converters for other folk and a bit of astute (OK lucky) trading means I'm not unreasonably out of pocket all told.


Steve Pavey27/10/2015 22:09:00
280 forum posts
32 photos

Mark is right - this was a first for me - although I have taken a few single phase motors apart to replace bearings and so on I haven't dug into the windings before. So I can offer the perspective of a first timer so to speak.

If your motor plate says 380v rather than 380/220 you'll have to take the end plate off the motor and locate the star point - I posted a couple of photos on the other thread, as did one of my 'advisors'. Looking back it wasn't particularly difficult and I would certainly tackle the same job again.

I think most inverters are capable of the functions you list - whether you need braking or not I don't know, but my Harrison has a mechanical clutch/brake so I didn't need the inverter to do this for me. I bought a Huanyang from an eBay seller called technical.jrs - apparently there are Huanyang copies around which are to be avoided. I did consider a known brand like Hitachi, Mitsubishi etc but they are considerably more expensive and I wasn't certain my motor conversion was going to be successful - given that uncertainty my dubious logic pointed me to a £90 solution rather than spend £250-300.

I also bought some shielded cable, decent push button switches, heat shrink sleeving and proper cable glands so I could make an attempt at some decent, safe wiring. Also I used a 240v DOL starter on the input side of the VFD to isolate it from the 16a supply (for some reason the manual says you mustn't do this and I can't see why - how would the VFD know whether the contacts are being closed by an electromagnet rather than a fleshy digit?).

Setting up the inverter is not easy because the manual is so confusing, but there are loads of forum posts around (this and other forums). I just set the motor up first (speed, amps, no of poles etc), and left all the external switching until I was a bit more conversant with the setup procedure. I got there with the help of several others who posted there setup parameters for me to work from. Be aware that many inverters are used with cnc spindles, and need very different parameters to the induction motors on a lathe or mill, so don't blindly copy the first list of parameters you come across.

Was it all worth it? Absolutely. I now have a little experience of a topic I'd only read about before, I'd happily do another one tomorrow and I also have a clear picture of my lathe's electrical system should I need to delve into it in the future. I've run the lathe for a few hours over the past week with no problems whatsoever.

Skel27/10/2015 22:33:42
12 forum posts
4 photos

Cheers guys.

Yes the motor plate says

240V 3 phase delta

414V 3 phase star

So no problem there.

Apparently all the M300/250 machines have this dual voltage motor.

Also, I have been told that there is an inverter available that can run the motor unloaded (belts off) and it will figure out its own running parameters on its own.

This sounds good to me. if only I could remember who told me..

I am also looking at the ones that Transwave sell, IMO Jaguar Cub.

They have a remote pod and the people there seem very helpfull and even call me back when they say they will,

which is something I like very much.

The bloke at Drives Direct seems helpfull also.

I dont mind spending a few hundred quid to get the job done right, first time.

A guy at work says that the ABB ones are best as they are very easy to program.

Lots of research to do..


Mark C27/10/2015 22:54:21
707 forum posts
1 photos

Jon (Skel?), just about all drives have the autotune function apart from the Huanyang drives. As far as make is concerned, they all do the same thing as far as basic speed control works - it tends to be the more complex things that set them apart (we could go into that but if you are starting out it will get confusing real quick).

Steve and Clive are bang on the money, for Steve, his setup will be almost identical to all other HY drives for these type of applications. Clive is also correct in advocating the output choke (load reactor) as I have fitted to all mine - they really make a difference as the drive manufacturers recommend (and this is definitely not a case of just getting add on sales). Also interesting to note the price of a commercial supply, that was not far of the 7.5 grand I was quoted - and they will not be keen to do it either (or certainly not for my property due to the layout).


Mark C27/10/2015 23:05:45
707 forum posts
1 photos

Jon, Muzzer suggested Inverter Drive Supermarket if you want the keenest prices available (better than I have ever managed for new). My previous favourite was Lamonde Automation but Muzzer trumped them BIG TIME!

Again, read the thread "Spot the connection" by Steve

As for subject passion, I just get a bit fed up reading all the opinions rather than accurate information from people that have actually done it but that is the way it is (so says Bill).


Skel15/12/2015 20:16:13
12 forum posts
4 photos

Hi Guys.

After lots of reading and head scratching I made a choice.

I went for an ABB inverter from inverter supermarket.

I also Got myself a jog button and a speed control knob.

Here is the list of components.

3 21302              
4 21693              
5 21690  

The whole lot came to £266.11 inc postage which I thought was very good.

Me and Hairy Dave wired it all up using the existing Harrison contactors so the lathe works as normal.

The extra speed control and jog function is very usefull.

Hope this helps others to make a choice when faced with the same quandry as me.



Edited By Skel on 15/12/2015 20:22:41

Chris Evans 615/12/2015 23:16:59
1627 forum posts

My 2 pennorth, and I profess to no nothing about the workings of electricity. I have a 3HP lathe with a motor that was not 240/440 and a 2HP Bridgeport that is 220/420 (voltages from memory) For cost reasons I bought a Transwave static inverter/converter and had Transwave come out to connect up for me. The lathe was and still is happy running from the set up but the mill would stop after a short time. Transwaves answer was to change to a rotary converter. To costly for me as the static job had cost £400. A friend suggested a cheap Chinese VFD for around £90 wired it up for me and the mill runs perfectly. Recent information from this board and I have the traverse working from 220 volts as well. I would buy the cheap inverter again when I add more machines to the workshop. I would need help in setting them up due to the "Chinglish" instructions.

Jon16/12/2015 22:08:11
997 forum posts
49 photos
Posted by Skel on 27/10/2015 22:33:42: Apparently all the M300/250 machines have this dual voltage motor.

The bloke at Drives Direct seems helpfull also

Apparently not all M300 are dual voltage, mine isn't just the coolant pump.

Helpful if theres a sale in it for them, wrong advice and still waiting for several hundred back from a sale.

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