Wadkin BGS 12" saw motor conversion

[Fitzroy]

The table you are referencing regards the size of fuse required, which is related to inrush current on startup. Motors pull lots of current when first starting, especially when cold. A VFD avoids this by spinning the motor up slowly via a ramp up in frequency. All you need is VFD rated for motor power.

F.

 

[jorgoz]

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[Ttrees]

The Wadkin manual states 29 amps for 220v 3ph 3hp. The 2.2 kw vfd is rated 10a, the 3 kw 13a and the 4kw 20a.
What is the correlation between what's stated in the manual and for those vfd's ?

Also the manual stated running the motor at low voltage might damage the motor.

Does that not indicate that it is a dual voltage motor???
as I said I'm not very knowledgeable on star motors.
As long as its wired up correctly , I cant see what can go wrong with a motor as long its running at correct speed
as it needs to be running at this speed for cooling itself. a good idea would be to feel the heat with your hand.
A good idea would be to open it up and check for dust anyway
get a marker before you do this and make one continuous line the length of the motor to aid assembly again
it will prob have grime on it so maybe tippex either, you get what i'm saying.

Have you read, or at least glossed over Bob Minchins induction motors pdf?
I run my machines from a 13a plug which is going to an MCB (a regular domestic hager 30a in the house which supplies power to shed)
as long as you dont have a RCD residual current circuit breaker your good to go, as the phantom earth current of the created third phase
prob will interfere with it and set it off.

That diagram looks like Chinglish VFD schematics
Four wires should be coming from the motor, 3 hots and an earth. (a 4 core wire just so ya know)
You have three wires from your household supply live, neutral and earth, this 3 core wire goes into the input of the inverter.
Inputs on some VFD's like the Huanyang are very small, ...( I have pictured these together so you can compare them side by side )

Its a good idea to mount the earths of both the household supply earth, and the motors earth to the VFD's protective cabinet, and have a single earth wire to go into the small earth terminal as trying to get two earth wires into that single terminal could strip the tiny screw threads.

I've posted this all before with piccys and such.
To me, this place insist the same anymore, so I'm not gonna go to significant efforts again as no one gives anymore.

If you feel you are stuck waiting to afford a VFD, or afraid of electricity as of yet, it might be a good idea to go about making VFD enclosures from something you can find.
Good luck

 

[jorgoz]

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[Farmer Giles]

So the u,v and w is where my pairs go, right ?

U, V and W in your diagram are the equivalent of L1, L2 and L3 in the diagram that I posted. Although you could in theory use the U, V and W terminals on the VFD to terminate the 6 wires, this is not the usual way, you extend this with a four wire cable, the three phases and earth, to the motor and there is a connection block on the motor that connects the windings in the selected mode and the 3 phases are connected.

The lower left hand connections on your diagram are for control inputs, the lettering for the 15v input seems to be next to the speed control potentiometer (if you fit one) and I think that should be on the connections below the three going to the potentiometer. No idea what the X1, 2 etc. are, could be digital inputs/outputs, you will need to read the manual to establish that. Typically there are inputs for on and off via momentary switches but the operation of the various inputs can change depending how you configure the VFD, so read the manual.

Cheers
Andy

 

[Ttrees]

These threads might be helpful if your researching VFD's and switches

can-anyone-fit-a-3-phase-inverter-for-me-t109500.html

huanyang-2-2kw-vfd-new-model-bought-in-2017-t107063.html

startrite-275-table-saw-conversion-3-phase-single-phase-t106896-30.html

Trying to find some piccys of the buttons you can buy for a quid or two each, with no luck
These should help though
Tom

 

[jorgoz]

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[Ttrees]

I cant get that ali express link up on my computer, and
I have seen only some of your pictures, one of which shows the inverter wired up, but I cant see it because
it is obscured at a weird angle, can you take another pic of it face on, no need for it powered on.
Both earths should go into the same terminal ...beware of false stamped/embossed earth sign!!!!
This happens with Huanyang!
I cant see, nor do you mention that you have both earths affixed to cabinet together, with one other wire attached to them to fit into that small earth terminal.

I would take the manual with a pinch of salt..not even a pinch actually.
These things dont do single phase out as far as I know.

I would be very wary of plugging in that VFD if its not wired up correctly, very especially regarding earth.
Dont hit that run button because these things could have a factory set parameter to suit a high speed spindle at
400HZ and not 50HZ as what European motors have... you would cook the motor running at that speed.
The same goes for motor pole number parameters!
2 pole motors running somewhere around 3000RPM
This goes for 95% of 2 pole motors as 2 pole motors run double the speed than 4 pole motors....Tablesaw has 2 pole
There probably will be parameter for 2 or 4 pole, but as well as that there may be a RPM parameter also.

If I could get a piccy of the VFD in question I might be able to point you to some threads with folks using them.
Tom

 

[Ttrees]

I had a look at the VFD you have bought..I cant get into ali express, but found some info from keepad pic in the manual you have posted.
It seems these inverters are branded Walfront or Hilitand.
Here is about the best info I could get from an Amazon page...

https://www.amazon.co.uk/1-5kW-Variable ... B0796TQ3R6

However, Its only the 1.5KW version, but from the looks of things you won't need to buy a relay for the run/stop buttons...
Unfortunatly it dosen't have the auto shut off fan technology, so I would doubt the next model up has either.
It also states it is not auitable for high inertia, but that could be either because of the size of the smaller unit, or they're just playing it safe.
Does it have a terminal for a braking resistor?
Even if it did, the hardware might not be installed.

How much did you pay for it?
Have you got another dual voltage motor to test it on?

Not much point in getting a regular electrician to look at these things...this is specific stuff.
There's folks on sawmill creek who are big into VFD's, they will be curious and knowledgeable, as some buy VFD's in quanitys.
Keep us posted

Tom

 

[jorgoz]

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[Ttrees]

Awaiting the images on my slow computer....so will comment which might be edited to an large amount threrafter....!
It no likey your pic hosting website.
The first thing to do with these is devices is do a parameter reset.... But Read below about Huanyang parameter reset sets to motor cook!!!!

If you look at the parameters on the two different drives I have linked comparing both, you will see the following...
The Huanyang drive has a lot more motor parameters to type in,
while the Isacon/askpower drive has much fewer parameters to enter the values in.
My VFD's seem to be a bit more straightforward, which should be understood easier... arguably
The layout of the parameters you describe sound similiar to the style of layout the Huanyang 4kw model uses, which someone was having trouble with on a planer on the SMC forum, if I've remembered correctly.

Do realise that these cheap VFD's are kinda made for HIGH SPEED spindles for CNC's, so you dont just follow those factory settings!
If you done so with the Huanyang you would have a motor on fire!
In Europe we run motors on 50HZ this relates to the motor speed.....with the magnetic difference in the land, the USA runs on 60HZ. (hertz)

It sounds as this VFD you have, that the start button might be a speed dial twist style, potientometer, or pot, like a guitar pickup pot.
with a clicking to start it like on the invertec (UKBrand) VFD's, IIRC from watching their videos.
I suggest you not use a potientometer on these VFD's as you might be putting strain on components like what happens with the Huanyang...
If you see my piccys you might see a pot which is now not in use, because of the problems it causes with lights in shed dimming, and it over currenting which led down a rabbit hole/stopped saw working for months, which after much reaserch work and luck I figured out how to fix it by dismantling it!!, bearing in mind I dont know anything about elektrickery!

[Just seen your pictures as of now, holy cow...Does it still work?
Taking a guess that it tripped ???
I was refering to this happening in the thread I was talking about

Always good practice to stick a phase tester to the grounded VFD cabinet, or machine in my cases as VFD cabinet is mounted to the saw
in the fashion I explained, both your earth cables will be bolted together, with another cable also going to the earth on VFD terminal, ideally.

Either buy some buttons for 2 quid or less each, as the thing will probably overload from using a pot
This may be part of what could be considered load, as you dont have the same quality chipboards as in the fancy VFD's,

But more so, you will probably damage your motor running it at much too fast, these motors aint cheap if your looking to buy a new one!!!
the motor should be 2870 RPM on ACM star machines as the nameplate states, and at 50HZ...
Not only that, but you have chosen to be ramping up a 24" bandsaw in 3 seconds!!!!
I would be weary of cooking my motor and the VFD doing so!!
I have selected about 7 seconds of a ramp up time on my VFD, I cant remember, but my belt is shot, so I take it easy on it...
likewise take it easy on the what I percive is the main idea of inertia load.
I have it running to a coasting stop...meaning no braking or maybe after 20 seconds, as I dont want to strain anything...
I rely on the mass of the wheels to do the grunt work instead of the VFD.
I have a card with my parameters

Could you start at the beginning again, and explain whats goin on with this VFD being taken apart?
I think I see bare wires in the VFD (looking a bit closer I think I see an earth wire from both the VFD and the motor. am I right on that?)
You can get little crimp on cable loop and spade plugs for the price of nails or screws from even a car shop.
One single crimp with a pliers or vicegrip flattening the tabs over the cable, crimped in the same orientation as the loops are,
Imagine, if made for a flat profile into slots.

Doing this on the cheap, as in not buying unneccairy part (relay) you can figure out which style of buttons you can choose for your particular model inverter...
My lightswitch is a bad idea and I'm going to revert back to the old buttons when I can get around to it.
If you want a preffered seperate big red stop and start , or a "button station" style switch you may have to buy a relay....you can check to
see if your VFD has one by testing with thin wire maybe one "core" from some broken electrical appliance, hoping that the wire can fit into
the seperate group of terminals as they're much smaller.
These are safe to touch and you can handle these to figure out if you want" three wire control " or a simple toggle switch.
I dont have the £4 relay inbetween (on the Isacon/askpower VFD, for it to work unfortunatly...

Carl holmgren has some ingenious methods of making a kick/knee paddle design to activate a simple toggle switch type if you want safety.
On my tablesaw I have a simpler desin, a paddle with a dowel, that just presses the button like a thumb.

To get the buttons to work ....
Figure the parameters to change operator to switches ...find out the two wires which join together to RUN/START it.
It might be labled "FOR" (on)..... and DCM (off) with hopefully a relay/pinky in the middle ,which on the huanyang is ..
("RST", not to be confused with the other main group of power terminals also called RST)
Pull apart to STOP...now get another wire to act as medium so you only need to strike the first like a match off the pair, instead of tying both wires togther.
to stop, pull the inbetweener apart from the other wire.
If the first method only works, then you need a toggle switch or something simple.... or buy the relay aswell.

Suitable link anyone ?

Tom

 

[jorgoz]

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[wallace]

That switch is a bit weird to have as a start/stop. That's an isolator switch. I believe to have the switch through the vfd you would need momentary buttons.

 

[Ttrees]

Delighted its working for you...you hooked this upto your bandsaw right?
For the switches you need either one type or the other, to find out what type is suitable (unless you want to fork out £4 or 5 pounds on a suitable relay....link appreciated
Get three short strands of core from some skinny electrical appliance
and test these in the seperate set of terminals which are for the switchgear, to find out which go together to turn it on
First though,
You will have to set a parameter so no other functions on the VFD will work (like the speed pot on the VFD, or stop and start)
so this in enabling the switches
So to be basic you can tie them togther for ON and pull apart for OFF, or buy a toggle switch
Or....
Try three wire control, for having a seperate on and off switch...
ON might be in FOR terminal, while OFF might be labeled DCM
Wires from these smaller set of terminals can be touched while the VFD is on, and theres no other suprises as in functions of the
other terminals that will make anything go crazy or anything

If three wire control works for you, you can cheaply buy a...
NO green start push button (NO normally open)
and a NC red stop button (NC normally closed), you can get nice big twist locking push buttons in your search for push buttons
or buy a button station instead...with no difference in quality I have found, infact I suspect counterfeit brand buttons in some cases :lol:

If two wire control is available only, without the relay get a toggle, or do as described.

If you do decide to uninstall it from your machine, remember to wait for the sufficent time for the capacitors to drain out!
as said in previous threads.

Good luck with your new machine
Tom

 

[MusicMan]

Hope you can figure out the command for a 10 s stop. That was set by H&S as they found that most saw accidents happened after the machine has been switched off. A Wadkin will coast for a long time before it stops being dangerous!

 

[Ttrees]

I must get the parameters that I have written down...
Within ten seconds is no problem for a VFD for my machines, a 24" bandsaw and 12" tablesaw.
For the tablesaw, a larger size is safer IMO, as you have more area for resting the timber on

 

[jorgoz]

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[Ttrees]

What was the problem with it?
It is the Griggio bandsaw which has a dual voltage motor that you have been working on first, right?
Tom

 

[jorgoz]

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[Ttrees]

Jorgoz , have you seen this recent thread?
topic113222-15.html

Tom