Wadkin PK20 Dimension Saw


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28 May 2019
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Can anyone help with advise about VFD / Inverters / single to 3 phase converters. I'm having real difficulty identifying such a beast suitable to run my PK. Welcome some help on this one.
Your pk will be 5hp. First you need to find out if the motor is dual voltage which entails looking at the tag on the motor. You might have to take the table off which is pretty challenging or you might be able to tilt the blade assembly and get a phone inside to take a picture of the tag. How many leads are coming out of the motor to the starter.
I just got a cheap vfd off ebay to run a wadkin UOS which is 5hp. I haven't tried it yet
https://www.ebay.co.uk/itm/NEW-VFD-VARI ... 2749.l2649
Bob/ Robert Minchin,myfordman on this site,or 9fingers elsewhere, has wrote an extensive PDF article
over on the woodhaven2, He's a mod there and you will find the link for the induction motor PDF underneath his signature.
The PDF is essential reading
There is plenty of diagrams on it, one of which shows a dual voltage motor terminals, that you might recognize when looking under the motor terminal housing lid of your own motor.
If the motor tag only states 380/440 volt only, this does not mean that it is not a dual voltage motor that can run on low (delta) voltage...
It could be anyways
There was a thread here about a year ago, where someone hooked up his Multico mortiser ...
Here it is..
This did not have the usual outlay that I've dealt with, and seen on other diagrams.

If it is a fixed star wound 380/400v motor, you have two choices concerning VFD's/inverters.

Option 1.
Buy a VFD with 380v OUT, Chinese VFD's for fixed high voltage out, are seemingly about 50% more expensive.

Option 2
Dig out the star point from the motor, like what Memzey has done in this thread.
https://www.ukworkshop.ums/post1234355. ... 5co.uk/for

I might try and find that Multico mortiser thread
Happy to help

If you are wanting a break for some time to digest it, you can take some time off to source some sheet metal, or a suitable box for the VFD if you haven't done so, and depending on budget making your own button station.
Some cable glands, some crimp connectors locally cost buttons
You might get a flimsy crimping plier tool cheaply in the poundshop
Some nice clear plastic for a window, and some hinges for the box.
If your doing this on a shoestring, depending on the VFD you choose, this might mean
buying a relay to go inbetween the on and off buttons, which are about 2 quid or less each on the bay.
This will be an NC button for stop, buy which style you like (NC normally closed), and a NO green for start.(NO normally open)
If you buy a push button station, the're about a tenner or more because your paying for the box.
You might still need a relay, depending if the VFD has a built in relay or not.
Don't be worried about the switches, Its way simpler than that sounds and you not need study them really,
Its more of a case of knowing if you need buy the relay now aswell as the switches, because they might take a bit of a wait to get'em here from the East.

Best to get a VFD that someone else has, as they can give you the parameters (motor commands)
that they used, some of these VFD's are more straight forward than others to program.

Make sure you don't hit run till your sure that your motor is correctly programmed to 50 HZ (speed)
and that its the correct motor pole number (speed)
These things are often factory default programmed to 400hz for high speed spindles, eight times the speed of our 50hz induction motors on this side of the pond. USA motors normally run at 60hz.

Make sure that you wait for those extremely high voltage capacitors to drain off, if you need go at the motor or input terminals for any reason. go in for a cuppa.

Having a plug between motor and VFD is not recommended, as it can let the magic smoke out if unplugged.

Read Bob's PDF
Good luck
Wallace, that looks like an Isacon/askpower drive.
I'm safely guessing that it will have the same auto shutoff cooling fan technology, as
seen in Jack Forsbergs Youtube videos.

Are you planning on having three wire control for this beast?, more specifically a start push button.
My 3hp Isacon/askpower has no built in relay...well that, or it was faulty,
My other Huanyang relay went faulty after swapping it over to another machine, as the Huanyang's have the fan humming all the time...
Swapped the panel for another front panel from an older Huanyang I destroyed from stalling a motor, and its great =D>
I don't know of anyone else with one, to find out if these have a relay or not.

I would be interested on what relay you get, if you do.

More interestingly, that's a two motor machine!
Hope you will shed some light on this, if you do one of your excellent resto threads in future. :D

Tom I've just been setting it up and I'm quite impressed by it. I only got it to test the motor that I got rewound for the UOS. I couldn't get the pulley off from inside the casting so I could only take the stator to my winders. I wanted to make sure it ran ok before it gets shipped off to Canada. I run a static in my shop but I might put this on my old planer.
The guy in Canada has bought a load of drives off Jack so he will be doing the final wiring.
The UOS has one motor that does the head and the feed gearbox. The drive didn't like trying to start the 18" head in 10 seconds but did well on 20 and stopped it in 25