Thread: Electrics on a Boley 5LZ lathe

Good to see it safely in it's new home.

As far as the electrics go, I'm of the opinion that it would be better to keep it as a 415V machine, and not try to convert it to 240. A phase converter would do nicely, or a 240 to 415 transformer to get 415 single phase, then an oversized VFD to generate the three phase. I think you'll need it to be oversized to handle the switching and reversing. Although not recommended by the VFD manufacturers, you can get away with it..

The automatic screwcutting, requires the electric clutch and motor reversals to work pretty smoothly, that's probably the main reason I'm suggesting keeping it 415 3ph...

Ray

At first look I don't like your chances.
To do what I think you're after "plug and play" you'll need a VSD at least this large
http://www.ebay.co.uk/itm/5-HP-240V-...item58bfad6cff (which needs a 30amp supply)

Is this a lathe that can be switch from FWD to REV without stopping?

Now maybe it can be made to work on a 3hp VSD(if the controls can be made to work on 240V) but there will be some rewiring.

Whats at the bottom of the base below where the 3 phase power line is?

Stuart

Hi Ray,
I see but your reply it does have "would it be called DOL reversing"?
Surely the currents for that would be huge?(I've seen the 1hp motor on Thoren's lathe and its pretty huge.. I assume that's why?)

Stuart

Originally Posted by Stustoys

Hi Ray,
I see but your reply it does have "would it be called DOL reversing"?
Surely the currents for that would be huge?(I've seen the 1hp motor on Thoren's lathe and its pretty huge.. I assume that's why?)

Stuart

Hi Stuart,

It's doable, but a little bit tricky. The trick is to allow enough time for the motor flux to decay before switching power back to the VFD. The instant you drop power to the motor, the motor becomes a generator for those few milliseconds it takes for the flux to decay, so there needs to be a sequence, motor contactor open, clutch, brake, delay, switch to reverse, motor contactor close. or something similar... all done without stopping or reversing the VFD. Basically treat the VFD like a phase converter.

As a rule of thumb the startup current would be 6x the rated current. The VFD will current limit anyway... so maybe size the VFD to 3 or 4 times the motor nameplate rating.

Ray

If the idea was to keep the electrics as original as possible and it's only a 1.8kW motor, wouldn't a rotary phase converter to go from single to three phase be the go? Plan B might be a single phase motor - say 2 kW or larger, slaved through a coupling or belt to a 3 phase generator. Clunky, but will do the job (One place I worked at used with different pulley sizes to drive their 60Hz based machinery). At least that way you don't have the voltage shocks that can kill VFD's.

As a minor point, those milk bottle fuses can be hard to find. I'd suggest you take one out now, note the details and start asking at your local electrical wholesalers. My mill takes a 6A version and I was told a 6 week leadtime to get them so spares are worth having. (If you have to buy a full box and they suit the mill I may be interested in splitting with you too - you only have two but I have 8 of those holders. I've only blown 2 so far...)

Michael

Originally Posted by RayG

It's doable, but a little bit tricky. The trick is to allow enough time for the motor flux to decay before switching power back to the VFD. The instant you drop power to the motor, the motor becomes a generator for those few milliseconds it takes for the flux to decay, so there needs to be a sequence, motor contactor open, clutch, brake, delay, switch to reverse, motor contactor close. or something similar... all done without stopping or reversing the VFD. Basically treat the VFD like a phase converter.

But as built doesn't the lathe just switch? So you have to add all that delay etc(not that that would be a problem for your good self)
Wouldn't it be easier to do the reversing with the VSD? You get to use a smaller VSD, you can use it as a VSD if you want. Though granted it depends on how easy it is to power the rest of the controls.

Having said that Another problem which I assume is the same as Thorens lathe is they can also DOL(?) pole change. Your way might work better than anything I've come up with so far.

Stuart

Originally Posted by RayG

Good to see it safely in it's new home.

As far as the electrics go, I'm of the opinion that it would be better to keep it as a 415V machine, and not try to convert it to 240. A phase converter would do nicely

Thanks Ray. Without you it would not be here . I was thinking the same thing about keeping it 415v. My limitation is 240v from a 15amp socket. I looked at a rotary phase converter but I read the sales literature () stating that the digital phase converters are new technology and better. I am not sure if that is true or not. I am happy to go either way assuming they can run off 240v 15a.

I really want to avoid a VFD if at all possible.

Originally Posted by Stustoys

At first look I don't like your chances.
To do what I think you're after "plug and play" you'll need a VSD at least this large
http://www.ebay.co.uk/itm/5-HP-240V-...item58bfad6cff (which needs a 30amp supply)

Is this a lathe that can be switch from FWD to REV without stopping?

Now maybe it can be made to work on a 3hp VSD(if the controls can be made to work on 240V) but there will be some rewiring.

Whats at the bottom of the base below where the 3 phase power line is?

Stuart

Stuart, that VSD is well beyond what I can run. I am limited to 15amp.

The lathe must be switched to OFF before it can be reversed by the looks of the rotary switches (first photo is motor speed, second is electromagnetic clutches).

IMG_2120.jpg IMG_2131.jpg

I was hoping I could run a 3hp Digital (or Rotary) phase converter? The motor is indeed massive for such little output.

I think the controls are actually 240v. I suspect that 415v is only used to run the motor. There are quite a few components in the cabinet that are marked ~200v. Note this is the schematic for a similar 5LZ - except it does not incorporate the screw cutting and is far less complicated.

boley_electrical_schematic.jpg

I am not sure about the box below the power.. it has two rather large (think Dolphin Torch battery size) coils. The plate on the box was attached above and seems to show a 415v stepdown to 240v. I assume this is to run the electrical switches(?). The obscured schematic shows it as a stepdown transformer..

boley_transformer_schematic.jpg IMG_2091.jpg
IMG_2128.jpg <-- And another transformer - this one is within the electrical cabinet (bottom right area).

Originally Posted by Michael G

If the idea was to keep the electrics as original as possible and it's only a 1.8kW motor, wouldn't a rotary phase converter to go from single to three phase be the go?

As a minor point, those milk bottle fuses can be hard to find. I'd suggest you take one out now, note the details and start asking at your local electrical wholesalers. My mill takes a 6A version and I was told a 6 week leadtime to get them so spares are worth having. (If you have to buy a full box and they suit the mill I may be interested in splitting with you too - you only have two but I have 8 of those holders. I've only blown 2 so far...)

Michael

Thanks Michael for the comment. I am hoping to go with your first option of the phase converter (rotary or other).

I assume the white things in the photo are the milk bottles? I will take your advice and hunt some down. If they are in packs I will keep you in mind. Last thing I want is to be high and dry because I have blown one.

All things considered, a phase converter is the best option, just a matter of finding the right one at the right price.

With the automatic screw cutting... how does it reverse the lead screw? I guess it has something to do with the clutches.... and gear box selector mechanism..

Ray

PS.. I take it that you can be trusted to match the FP2 colour scheme

Looking at the transformer with the 220V primany got me thinking. We are assuming(I think) the controls are 415V(or steped down from 415V). They maybe 220V. How many wires in the 3 phases input cable? Maybe it has a 5 pin plug?

Stuart

Originally Posted by RayG

PS.. I take it that you can be trusted to match the FP2 colour scheme

Which one? His FP2 is - err - 2 tone. Or is it 3?

Someone - I think it was RC - once said you could use a big welder to generate 415V? I know my big old stick welder has a choice of inputs as I've run it on 240V and currently run it on 415V 3 phase. Is this another way of building a phase converter or something I got wrong/forgot vital details?

I've got a spare 7.5HP 3 phase motor doing nothing ATM that could be used as the basis of a rotary phase converter but somehow I don't think you're going to start it on a 240V 15A supply......

Next time I'm up I could take a look at your board & its access. Getting an electrician to run a 32A single phase line to the garage might be do-able. Lots of problems go away if you throw enough money at them.

PDW

G'day Variant,
Congrats on the new lathe, I had a bit of a look at it during the auction and that quick retracting tool post was a fancy looking jigger. Did you have a crack at the Bolley turret lathe? For $250 plus rip it might have had some parts in common for cheap spares.
I use a Phase Changer RPC for my mill and it works great, I didn't want to use a VFD because it would mean having to disable the break motor which is a very handy feature.
Regarding those fuses, two of them were blown on my mill and I just bought some correct rated fuse wire and fixed them myself, just pull one of the caps off and collect the sand that's inside then unsolder the two fuse wire remnants, feed the new wire in, solder the first end, pour sand back in and solder the other cap back on. If yours aren't soldered just drill a 1.5 mm hole in the centre of each cap to feed the new wire through.
Good luck with what should be an interesting project.
Cheers,
Greg.

Originally Posted by variant22

I am the mystery buyer of a certain Boley 5LZ lathe (huge thanks to RayG and PDW for their help in getting it landed). I figured I would start this thread as a place holder for getting it up and running from an electrical perspective.

Now that it has arrived and I have checked out the motor. It looks like it is a 2 speed 415v motor. It has no markings on the plate (first photo below) suggesting that it is able to run on 240v. Given the lathe has a whole bunch of complicated electronics I figure my best approach might be to buy one of those UK Drives Direct inverters that take 240v single phase and convert it to 415v three phase.

I am not all that keen on trying to interface the 5LZ electronics with a VFD if I can avoid it (incidentally it has coils on the side of the machine and a plate referencing 240v..fourth photo). I would like to wire a plug to a phase converter (like the one linked above) and be done with it.. big dreams huh?

Some things to consider about the electronics on the lathe:
- Rotary switch for motor - FWD/REV
- Rotary switch for electromagnetic clutches - FWD 1:4/BRAKE/REV 1:1 speed Auto-screw cuting 1 & 2
- Electronic brake
- Ton of electronic stops
- And an automatic 1.4x speed reversing mechanism as part of an automatic screw cutting attachment
- Coolant pump switch / light / buttons

Is there anything I am missing here or is this (Drives Direct) a good way to go? Are there any reasons why the existing electronics (assumed connected) will not work running this type of phase converter setup?

* Gratuitous last photo of the Boley's new home.. - If there are any other 5LZ owners out there please drop me a line. I am desperately searching for a legible schematic (one that has the screw cutting electronics).

IMG_2018.jpg IMG_2029.jpg IMG_2097.jpg IMG_2053.jpg IMG_2069.jpg IMG_1978.jpg

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congratulation's . i almost bidding against you but decided not to as I'm have too many already
very nice lathe . we are the same boat now as to fire them up .
cheers
Peter

Originally Posted by RayG

All things considered, a phase converter is the best option, just a matter of finding the right one at the right price.

With the automatic screw cutting... how does it reverse the lead screw? I guess it has something to do with the clutches.... and gear box selector mechanism..

Ray

PS.. I take it that you can be trusted to match the FP2 colour scheme

I assume the one I picked above (3hp) is not going to be big enough (thanks Stuart). Maybe a 5hp one?

Funnily enough I have the manual open to the page about the reversing; "The reversing gear mechanism contains a direct gear, a transmission gear 1:4 with opposite rotation direction and a brake; the control being affected by means of electro-magnetic multi-disc clutches."

As for the colour scheme.. see below..

Originally Posted by Stustoys

Looking at the transformer with the 220V primany got me thinking. We are assuming(I think) the controls are 415V(or steped down from 415V). They maybe 220V. How many wires in the 3 phases input cable? Maybe it has a 5 pin plug?

Stuart

I checked the input cable - it has a 4 pin plug. Any help?

Originally Posted by PDW

Which one? His FP2 is - err - 2 tone. Or is it 3?

Someone - I think it was RC - once said you could use a big welder to generate 415V? I know my big old stick welder has a choice of inputs as I've run it on 240V and currently run it on 415V 3 phase. Is this another way of building a phase converter or something I got wrong/forgot vital details?

I've got a spare 7.5HP 3 phase motor doing nothing ATM that could be used as the basis of a rotary phase converter but somehow I don't think you're going to start it on a 240V 15A supply......

Next time I'm up I could take a look at your board & its access. Getting an electrician to run a 32A single phase line to the garage might be do-able. Lots of problems go away if you throw enough money at them.

PDW

I guess the secret is out. The FP2 is at least 2 tone (Grey originally, then Greened up for the 1980's). 3 tone if you count the purple slotting head I have kicking around. I tried to get it back to grey, and did a half reasonable job. By the time it came round to rubbing metho on the long reach head my VFD had arrived and all of a sudden had a usable machine.. One of these days I will crack open the metho and get it back to grey.

32amp line might be a longer term option. Although I am not sure what the difference would be between having a 32amp and a 3ph rigged? If it has to come from the street it might well have to go under my driveway... Last time I checked about the 3ph the electrician offered to do it if I dug the trench. I think it might have had to be 600 deep and at that depth we were hitting rock. Nothing but a whole bunch of rock up here and no street posts - only underground cabling.

Good to see her home A.

Don't underestimate the power draw required on startup/plug reversing. I ran the Holbrook for a short time on a 2hp Danfos VFD. I still want to run it on a VFD to fill the gaps in the speed range. Anyway the 2hp motor would overload the VFD when engaging the clutch in top speed. The VFD showed a peak load of 5.4KW. Despite being 2hp the motor is twice the size of the 6hp in the Vernier.