three phase lathe to single phase

[doubleboost]

I have found Transwave to be very helpful
It would cost nothing to give them a bell
There are not many problems they have not come up against
I still prefer to be able to use all the machines original switches pumps lights etc
Especially the reverse lever

 

[powderblast]

Im going to give them a call first and see what they have to say i would prefer to keep the lathe original, im hoping it was because the motor was wired in star and should of been in delta?

i will let you all know what they say.

 

[Bill Edwards]

If you go the vfd route I would use the cheap Chinese one as they work and cost less than uk stuff.

I would also use the original switch gear to control the inverter rather than a pendant, even though it requires some work. Find somewhere to put a dial for the speed knob and you should be sorted. Much nicer keeping it original.

Once the vfd is programmed to the motor that's it, set for life.
My inverter lives out of sight in the cabinet which is bolted shut. I don't need to see it as it's wired to external switches.

 

[powderblast]

Just spoken to transwave really helpful but they said that maybe that machine does not suite a converter look at the rotary or inverter route

 

[powderblast]

Hi i have re spoken to Joe at transwave he suggests just to use an inverter so i bought the

2hp/1500W IMO XKL Inverter & Remote Control Station Package - Ideal for Lathe
MOTOR CONTROL FROM YOUR SINGLE PHASE SUPPLY £290.00

I could of maybe got it all cheaper buying separate but they have great customer service and i felt reassured that i can ring them with the installation.

He says i need the change the motor by putting the straps down instead of across?

Hopefully this get the machine working and i will just use the control box
Im hoping i can wire the coolant and light up to a separate plug and hopefully some one on here can tell me how???

thanks for all your help

 

[Bill Edwards]

Of course we can tell you how. Other people can tell you better but I can manage if necessary once at a computer.

 

[powderblast]

I have now wired up into delta so i just need to wait for the inverter now

 

[powderblast]

Heres the wiring into the coolant pump

 

[powderblast]

I have found Transwave to be very helpful
It would cost nothing to give them a bell
There are not many problems they have not come up against
I still prefer to be able to use all the machines original switches pumps lights etc
Especially the reverse lever

I have got an inverter and a control box ordered from them but i need to run the coolant pump independently im sure i have watched one of your videos on this do you know what i need to do to get this running from a plug? thanks

 

[Seadog]

Hi i have re spoken to Joe at transwave he suggests just to use an inverter so i bought the

2hp/1500W IMO XKL Inverter & Remote Control Station Package - Ideal for Lathe

I think you could run into trouble with that invertor. My limited experience tells me that the invertor should be rated higher than the motor. That's why I suggeste a 2.2kW unit earlier in the posts. I bought a secondhand invertor, which had been supplied by Drives Direct, that matched the motor (1hp) and the damned thing kept overloading. I spoke to DD and he explained that I needed a larger invertor. I ended up with an Invertek 1.5hp and I've not had a single issue.

 

[powderblast]

I think you could run into trouble with that invertor. My limited experience tells me that the invertor should be rated higher than the motor. That's why I suggeste a 2.2kW unit earlier in the posts. I bought a secondhand invertor, which had been supplied by Drives Direct, that matched the motor (1hp) and the damned thing kept overloading. I spoke to DD and he explained that I needed a larger invertor. I ended up with an Invertek 1.5hp and I've not had a single issue.

I actually spoke to transwave direct and this is the one they said would do the job he then said all i need to do is keep the lathe gears in lever one high and lever two in speed 2000 (basically have it set in its highest speed) and then just use the control box iteself to set the speed, he said that using levers and gears ect is outdated and this control style is the new way of doing it, i can only take his word as i dont have a clue i hope i dont have any issues with it because ive had enough set backs with it.

 

[graffian]

By the sound of it your lathe contactors have cutouts, you might find they have
enough range so you can just turn them up, or just remove them.
My experience with a static converter was one line was much hotter than the
others and the motor ran hot; I had it running a 3phase polisher and having it running all day long wasn't unusual.

Statics tend to have quite different voltage. I have a home made rotary and they are
all equal, they are all equal when running the motor it was tuned for under the load
it was under; it's been faultless and in everyday use for 13years.

 

[powderblast]

By the sound of it your lathe contactors have cutouts, you might find they have
enough range so you can just turn them up, or just remove them.
My experience with a static converter was one line was much hotter than the
others and the motor ran hot; I had it running a 3phase polisher and having it running all day long wasn't unusual.

Statics tend to have quite different voltage. I have a home made rotary and they are
all equal, they are all equal when running the motor it was tuned for under the load
it was under; it's been faultless and in everyday use for 13years.

I have already got a inverter and control box on its way to me now hopefully once this is installed no more issues

 

[addjunkie]

Only down side of running the machine on top speed and using the inverter to control the speed, if when you need the back gear.

Advantage of a rotary convertor itll run lights suds pump too..

So many variables to ponder. id just change suds motor lamp etc to single phase

 

[Seadog]

Apart from the convenience of using a rotary converter, the difference from a stock machine to the 'New Improved' one, when fitted with a VFD, is, IMO, worth any amount of hassle.

 

[Seadog]

That could be an issue. From my own experience it's not been a problem for me, and I have had the lathe running very slowly for minutes at a time when I was winding some coils. Considering my motor is a 1950s vintage from a Raglan I'm quite surprised.

 

[WorkshopChris]

That could be an issue. From my own experience it's not been a problem for me, and I have had the lathe running very slowly for minutes at a time when I was winding some coils. Considering my motor is a 1950s vintage from a Raglan I'm quite surprised.

The odds are your motor was designed and specified by a team of engineers, expecting it to work hard and forever. A new motor will be built to the lowest possible price by a team of accountants.

 

[powderblast]

The odds are your motor was designed and specified by a team of engineers, expecting it to work hard and forever. A new motor will be built to the lowest possible price by a team of accountants.

so if it is an issue could you just have the control on the inverter set to max and then just use the lathes gears for the speed????

I assume the original way it was set was that the motor will just spin at the same speed and its the gears of the lathe that slows or speeds things up??

 

[WorkshopChris]

yes if you want a slow speed it would be better to use the lathe gearbox to drop speed then fine tune with the vfd.

 

[daleyd]

Yeah - as said above there's no need to leave it one gear, though by varying the motor speed you obviously remove the need to change gear for a big chunk of the speed range. But by combing the vfd with the gearbox you get a vast range of speeds available that you wouldn't get with just the gearbox and fixed speed motor, particularly in the low gears for screwcutting where having a "really" slow speed will help a lot.

What you don't want to do is leave the motor running/labouring at low speeds for long periods. To overcome this you normally set your minimum speed on the vfd at something like 15/20hz to maintain the cooling effect. If the speed is still too fast then drop down to the next gear or 2.