jorgoz
Established Member
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Wadkin BGS 12" saw motor conversion
- Thread starter jorgoz
- Start date
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No, you can get 415V 3 phase investors that run off 220V single phase. I use Drives Direct, have three which have run very satisfactorily for several years of hobby use. The 415V ones are dearer, but in my view well worth it.
jorgoz
Established Member
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deema
Established Member
There are probably three solutions you could look at
1. Rotary orcstatic converter. Rotary bring the most expensive but either is not cheap. The main advantage is you can then run any 3ph machine within the units power capacity.
2. Exchange the motor and DOL or direct in line starter. That’s the box you show in your picture. Probably the easiest solution and I’ve that will add value to your saw when the time comes to sell it. I would upgrade the motor to the largest that will fit (the frame size is found by measuring from the centre of the spindkecto the bottom of the base. You can probably fit a 3Kw motor or worst case a 2.2KW
3. Fit an inverter. If you lucky the motor may have the Star Delta connections already. If not this will require for the most economical solution opening up the motor finding the Star point where the ends of the coils are connected; cuttingvrhem and bringing tails out. Sounds complex but it’s realky easy.
This conversion costs about the same as replacing the motor. However it does not add value to you saw, and you don’t get the advantage of having a nice new shiny more powerful motor.
I would change the motor if it were my saw.
1. Rotary orcstatic converter. Rotary bring the most expensive but either is not cheap. The main advantage is you can then run any 3ph machine within the units power capacity.
2. Exchange the motor and DOL or direct in line starter. That’s the box you show in your picture. Probably the easiest solution and I’ve that will add value to your saw when the time comes to sell it. I would upgrade the motor to the largest that will fit (the frame size is found by measuring from the centre of the spindkecto the bottom of the base. You can probably fit a 3Kw motor or worst case a 2.2KW
3. Fit an inverter. If you lucky the motor may have the Star Delta connections already. If not this will require for the most economical solution opening up the motor finding the Star point where the ends of the coils are connected; cuttingvrhem and bringing tails out. Sounds complex but it’s realky easy.
This conversion costs about the same as replacing the motor. However it does not add value to you saw, and you don’t get the advantage of having a nice new shiny more powerful motor.
I would change the motor if it were my saw.
wallace
Established Member
Have you got a pic of the motor tag? Even if it doesn't say dual voltage they generally are. Like already mentioned you can alter the motor windings to make it low voltage. The last one the winders did for me cost £20.
If you don't mind loosing a bit power you could use a static converter
If you don't mind loosing a bit power you could use a static converter
jorgoz
Established Member
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jorgoz":310etlj4 said:
Roughly. A 2 HP one is currently £460. It will add something to the value of your saw, though. It also gives you the benefit of software control, e.g. soft start, controlled stop within 10 seconds.
You have such a good saw there that it is worth keeping it running, one way or another.
wallace
Established Member
Take a picture of inside the motor terminal box. The last lathe I did never had dual voltage on the motor tag but by just adding some terminal strips changed it to low voltage then I could use the cheap VFD's for £100
jorgoz
Established Member
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deema
Established Member
You have six wires coming out of the motor which means that you can configure it to be a low voltage motor (240v, 3ph) by just wiring it up in delta. Three of the wires at the moment will be all joined together in what is called Star configuration (415v, 3ph)
wallace
Established Member
There you go that's saved you a whole load of grief swapping motors and such.
Just get yourself a cheapo vfd, you don't need the starter you have now. I have used the cheap ones a few times and they seem ok. I got one of these for a machine but you will have to have a look for a bigger KW one.
https://www.ebay.co.uk/itm/1-5KW-220V-2 ... SwXYtYwP0M
Just get yourself a cheapo vfd, you don't need the starter you have now. I have used the cheap ones a few times and they seem ok. I got one of these for a machine but you will have to have a look for a bigger KW one.
https://www.ebay.co.uk/itm/1-5KW-220V-2 ... SwXYtYwP0M
topchippyles
Established Member
I have a 5.5 HP 3 phase converter available at a very good price and just been serviced today as it happens,Might need to check the start up load on the motor but it runs my 2 hp 3 phase bandsaw fine,I have a 15 hp rotary converter which cost me £1500 new as my main supply in my workshop.
Ttrees
Iroko loco!
Although I have only seen inside three motors , which were all dual voltage..it seems to me it could be wired up for use with an inverter.
There are four rows of terminals, but markings on three rows which could possibly indicate dual voltage.
It looks like it could allready be wired in delta as there are three paired 'straps'
However I don't see where you could put these if you had wired it in star,...ie where to stack one of the
straps.
I believe the only thing that could wrong if you wired up a hundred quid VFD is that you would have
hardly any torque with a star motor
I visually checked the consumption of my dual voltage 3HP 24" bandsaw setup with Isacon/Askpower VFD at my meter the other day, running a 3/4" blade, and not cutting anything
Just looking at the wheel spinning, It gave little more draw than an old laptop which has had its day.
Quite efficient, these VFD's are with the saw, seen as most things I cut the machine dosent notice,
likewise with the Startrite 12" saw.
I would get an isacon/askpower drive as the cooling computer fan has auto shutoff.
If you do get this drive you need to get a relay along with the buttons if you want a button station.
(ie three wire control) an on button and an off seperate)
The Huayang's have relays built in, but no auto fan shutoff tech.
If go dont buy a cheap 2 quid relay you will need a toggle switch like on Carl Holmgren's videos
look his tablesaw button.
I have allocated this drive for the bandsaw because I never bought a relay, and have just a crappy hosuehold lightswitch for the job.
The soft rocker does not turn off all the time when you press it.
Not suitable for a tablesaw. Get a relay and make your own switch control box, or buy a plastic button station.
There are four rows of terminals, but markings on three rows which could possibly indicate dual voltage.
It looks like it could allready be wired in delta as there are three paired 'straps'
However I don't see where you could put these if you had wired it in star,...ie where to stack one of the
straps.
I believe the only thing that could wrong if you wired up a hundred quid VFD is that you would have
hardly any torque with a star motor
I visually checked the consumption of my dual voltage 3HP 24" bandsaw setup with Isacon/Askpower VFD at my meter the other day, running a 3/4" blade, and not cutting anything
Just looking at the wheel spinning, It gave little more draw than an old laptop which has had its day.
Quite efficient, these VFD's are with the saw, seen as most things I cut the machine dosent notice,
likewise with the Startrite 12" saw.
I would get an isacon/askpower drive as the cooling computer fan has auto shutoff.
If you do get this drive you need to get a relay along with the buttons if you want a button station.
(ie three wire control) an on button and an off seperate)
The Huayang's have relays built in, but no auto fan shutoff tech.
If go dont buy a cheap 2 quid relay you will need a toggle switch like on Carl Holmgren's videos
look his tablesaw button.
I have allocated this drive for the bandsaw because I never bought a relay, and have just a crappy hosuehold lightswitch for the job.
The soft rocker does not turn off all the time when you press it.
Not suitable for a tablesaw. Get a relay and make your own switch control box, or buy a plastic button station.
jorgoz
Established Member
deleted
Ttrees
Iroko loco!
I reckon, if it is a dual voltage motor, that it is allready in delta mode.
and to revert it to star would possibly omit use of the terminals because there's
nowhere to place those straps to join those three black wires together.
Those black wires which are marked on the plastic terminals.
The fact there's a joint before the terminals with six wires indicate these are the star
windings.
Nothing to loose from getting a VFD I reckon.
Have you typed in some info of that motor into google?
I reckon Bob Minchin would know, why don't ya ask him?
He can alter good brand VFD's to work with star only motors too
Good luck
and to revert it to star would possibly omit use of the terminals because there's
nowhere to place those straps to join those three black wires together.
Those black wires which are marked on the plastic terminals.
The fact there's a joint before the terminals with six wires indicate these are the star
windings.
Nothing to loose from getting a VFD I reckon.
Have you typed in some info of that motor into google?
I reckon Bob Minchin would know, why don't ya ask him?
He can alter good brand VFD's to work with star only motors too
Good luck
deema
Established Member
I would recommend that you get an electrician to carry out the conversion. It’s not difficult and won’t take very long and shouldn’t be very expensive.
Just ask them to wire your 240V 3ph motor to a suitable inverter with (if you want it) regs compliant braking I.e. must stop with the largest circular saw mounted within 10 seconds (it may require a braking resistor to be added). I would ask for an IP60 inverter and for it to be mounted discretely within the cabinet. The IP rating means that it is dust proof. Once a week just check that it’s not covered in Saw dust around the fins that allow it to cool.
Having said all that I would again recommend getting an electrican to swap the motor out for a single phase motor which will in total be about the same price and add value to your Saw. An inverter conversion does seem to detract from a saws value.
Just ask them to wire your 240V 3ph motor to a suitable inverter with (if you want it) regs compliant braking I.e. must stop with the largest circular saw mounted within 10 seconds (it may require a braking resistor to be added). I would ask for an IP60 inverter and for it to be mounted discretely within the cabinet. The IP rating means that it is dust proof. Once a week just check that it’s not covered in Saw dust around the fins that allow it to cool.
Having said all that I would again recommend getting an electrican to swap the motor out for a single phase motor which will in total be about the same price and add value to your Saw. An inverter conversion does seem to detract from a saws value.
Hi,
I went through pretty much the identical thing on my Wadkin planer. I solved it myself by:
- Opening up the motor and finding the 'star' point
- Breaking into the star point and installing three additional wires(tails) from the star point to take outside of the motor.
- Reconfiguring the motor from 'star' to 'delta'
- Buying a VFD from ebay and wiring the motor directly to the VFD
- Reconfiguring the original DOL to run off of 220v to act as a run/no run signal to the VFD.
It took me a good few hours research to get comfortable with what I was going to attempt, but was not overly difficult once I got my head around the system. It was the technical terms that take time to understand so i'll give you my view.
Motor vs DOL, and Star Point. Below is excerpt from Wadkin Manual.
- The motor is represented by the three coils on the left, each coil is a winding in the motor.
- The Star point is where three ends of the windings are connected together.
- The DOL (Direct-on-line) is the bit you have been photographing with all the wires attached, and is one the right of the figure. The DOL is basically a switch within a switch. You push the on button and create a circuit through a relay, this closes the main circuit that carries the electricity to the motor. The reason you have this arrangement is so that the full start current for the motor (could be 20+ amps) does not flow through the switch under your finger!
Star (or Y) configuration vs Delta configuration. Drawing below (excuse my art work) shows a representation of the motor. On the left the three windings are joined at the central point (star) and the three leads/wires/tails (green lines) connect to the DOL. In star configuration the star point represents a neutral point and the voltage across the motor becomes 440v (2x220). On the right the motor is in Delta config, and voltage across the windings becomes 220v, again green wires represent the leads to the DOL.
Normally on the outside of the motor you have a junction box, and in this box you join the ends of the winding (a,b,c,d,e,f) in either star or delta configuration, and from this box you take the leads to the DOL. Two pictures below show such a junction box in star (Y) and delta, in star mode (bottom picture) you can see all the ends connected together using copper jumpers.
In your case it look like the tails from inside the motor are just connected together (in whichever configuration) and covered in insulation tape, with wires taken off to the DOL. If you undo these connections you'll be left with six tails exiting your motor, you can then use a multimeter, or a battery and bulb to workout which of the six tails are the start and end of the same winding, ie a-b, c-d, e-f. You can then connect back together in delta configuration (i'd use a terminal block) and take leads off to your VFD.
Using a VFD:
- The VFD has to be connected direct to the motor, you start and stop the motor from the VFD, you do not need a DOL.
- Setting up the VFD is also not that tough but they do have lots of settings and you need to watch a couple of youTube videos, reference the instruction manual (normally written in Chinglish) and get the settings correct.
- The VFD can use an external switch to tell it to run or stop. I rewired the Wadkin DOL, incorporating a £7 relay from ebay, to act as the start/run signal to the VFD. This was a little more involved but meant I retained the original start/stop switch, which i liked.
I really enjoyed learning about three phase motors and getting the system to work for minimum outlay (c.£100), I wanted to try to give you an impression on what was involved as i'd hate you to give up just because you couldn't find the information to understand the problem. Hope some of that helps.
Fitz.
PS. I am not an electrician, I am a DIY enthusiast. Chemical Engineer by background with what I'd say is a good ability to understand technical problems, and reasonable wiring/soldering skills. I understand electrics are very dangerous, the need for isolation, and the risks involved if you wire something up wrongly.
I went through pretty much the identical thing on my Wadkin planer. I solved it myself by:
- Opening up the motor and finding the 'star' point
- Breaking into the star point and installing three additional wires(tails) from the star point to take outside of the motor.
- Reconfiguring the motor from 'star' to 'delta'
- Buying a VFD from ebay and wiring the motor directly to the VFD
- Reconfiguring the original DOL to run off of 220v to act as a run/no run signal to the VFD.
It took me a good few hours research to get comfortable with what I was going to attempt, but was not overly difficult once I got my head around the system. It was the technical terms that take time to understand so i'll give you my view.
Motor vs DOL, and Star Point. Below is excerpt from Wadkin Manual.
- The motor is represented by the three coils on the left, each coil is a winding in the motor.
- The Star point is where three ends of the windings are connected together.
- The DOL (Direct-on-line) is the bit you have been photographing with all the wires attached, and is one the right of the figure. The DOL is basically a switch within a switch. You push the on button and create a circuit through a relay, this closes the main circuit that carries the electricity to the motor. The reason you have this arrangement is so that the full start current for the motor (could be 20+ amps) does not flow through the switch under your finger!
Star (or Y) configuration vs Delta configuration. Drawing below (excuse my art work) shows a representation of the motor. On the left the three windings are joined at the central point (star) and the three leads/wires/tails (green lines) connect to the DOL. In star configuration the star point represents a neutral point and the voltage across the motor becomes 440v (2x220). On the right the motor is in Delta config, and voltage across the windings becomes 220v, again green wires represent the leads to the DOL.
Normally on the outside of the motor you have a junction box, and in this box you join the ends of the winding (a,b,c,d,e,f) in either star or delta configuration, and from this box you take the leads to the DOL. Two pictures below show such a junction box in star (Y) and delta, in star mode (bottom picture) you can see all the ends connected together using copper jumpers.
In your case it look like the tails from inside the motor are just connected together (in whichever configuration) and covered in insulation tape, with wires taken off to the DOL. If you undo these connections you'll be left with six tails exiting your motor, you can then use a multimeter, or a battery and bulb to workout which of the six tails are the start and end of the same winding, ie a-b, c-d, e-f. You can then connect back together in delta configuration (i'd use a terminal block) and take leads off to your VFD.
Using a VFD:
- The VFD has to be connected direct to the motor, you start and stop the motor from the VFD, you do not need a DOL.
- Setting up the VFD is also not that tough but they do have lots of settings and you need to watch a couple of youTube videos, reference the instruction manual (normally written in Chinglish) and get the settings correct.
- The VFD can use an external switch to tell it to run or stop. I rewired the Wadkin DOL, incorporating a £7 relay from ebay, to act as the start/run signal to the VFD. This was a little more involved but meant I retained the original start/stop switch, which i liked.
I really enjoyed learning about three phase motors and getting the system to work for minimum outlay (c.£100), I wanted to try to give you an impression on what was involved as i'd hate you to give up just because you couldn't find the information to understand the problem. Hope some of that helps.
Fitz.
PS. I am not an electrician, I am a DIY enthusiast. Chemical Engineer by background with what I'd say is a good ability to understand technical problems, and reasonable wiring/soldering skills. I understand electrics are very dangerous, the need for isolation, and the risks involved if you wire something up wrongly.
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jorgoz
Established Member
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Farmer Giles
The biggest tool in the box
jorgoz":227eb1g7 said:deema":227eb1g7 said:
Thanks all for helping me.
How do I just wire it delta ? All wires are black
There are six wires, 2 for each winding. Use a multimeter to find which ones are pairs. It doesn't matter which end of each winding goes where so once you have found the pairs, label the ends U1 and U2 for the first pair, V1 and V2 for the second pair and W1 and W2 for the third.
The following diagram should show you how to wire it up. L2, L2 and L3 are the 3 phases from your VFD. The top diagram is the schematic diagram, the bottom shows how to place the straps on a modern motor to get delta however you don't have to do it that way, 3 terminals will do it, each with one end of two different windings and a phase from the VFD as per the diagram. While you have your meter out, make sure none of the windings go to earth, i.e. the case of the motor and that each winding is isolated from each other, i.e. if you have more that two ends that have continuity with each other then you have a short.
Once you have it running, if the motor is going in reverse, swap L1 and L2, or any two of the phases form the VFD and it will go the correct way.
SAFETY - make sure the motor is earthed, check continuity between the case and earth with a meter. Also don't apply power with the covers of anything off. If your not comfortable and/or don't have a competent person to check it, don't do it.
Cheers
Andy
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jorgoz
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