[Steve303]

I am looking at a used mini mill with the optional high voltage 3 phase transformer. Anyone know if this mill can be run on 2 phase power with the transformer installed.

[Al_The_Man]

By 2phase I assume you mean N.A. 240v?
If so, This is actually 1ph, you need 3 conductors for 2 phase, and even if you do have 2 phase, it will not work.
Al.

[Steve303]

By 2phase I assume you mean N.A. 240v?
If so, This is actually 1ph, you need 3 conductors for 2 phase, and even if you do have 2 phase, it will not work.
Al.

Thanks Al. I in Canada so that right is 240V. The base Haas Mini Mill runs on 240V or 3 phase with the optional factory installed 3 phase transformer. I am hoping to by pass the transformer and run 240V as I don't have 3 phase in the shop beside my house.

[Al_The_Man]

What is the controller on the Haas? Fanuc?
Al.

[Steve303]

It has the Haas control.

[Al_The_Man]

Any support from Haas in order to get an answer?
Al.

[Titaniumboy]

I am looking at a used mini mill with the optional high voltage 3 phase transformer. Anyone know if this mill can be run on 2 phase power with the transformer installed.

That should be a nice upgrade in capability from your Novakon Pulsar. I’m jealous.

[Steve303]

Any support from Haas in order to get an answer?
Al.

Never received a yes or no answer from Haas or the local Haas Outlet only a maybe or maybe not. I got the feeling they don't like talking about order mills.

[Steve303]

That should be a nice upgrade in capability from your Novakon Pulsar. I’m jealous.

Not happening .... yet. Still looking - too many unknowns with this mill. I wanted to see the machine under power with a friend but the seller kept saying I could not due to covid. So I took a pass. I even reorganized my shop to make space for it.

[mactec54]

I am looking at a used mini mill with the optional high voltage 3 phase transformer. Anyone know if this mill can be run on 2 phase power with the transformer installed.

What is the voltage of the optional High voltage transformer

The standard Mini Mill will run fine on Single phase 240v 2 Hot wires and a Ground

This is called single phase or split phase for NA not 2 phase

[mactec54]

I am looking at a used mini mill with the optional high voltage 3 phase transformer. Anyone know if this mill can be run on 2 phase power with the transformer installed.

How old is this machine, post some photos in the back control panel the Transformer and the disconnect

[Steve303]

What is the voltage of the optional High voltage transformer

The standard Mini Mill will run fine on Single phase 240v 2 Hot wires and a Ground

This is called single phase or split phase for NA not 2 phase

That's my error. Single phase is what I should have put in the title. It's a 2001 mini mill. It has been running with 3 phase with the optional transformer. No one would say with any certainty weather it would run on single phase. I've since decided to take pass on it.

I am still looking but decided a mini mill 2 would be a better option with the 20 tool changer and additional Z height.

[mactec54]

That's my error. Single phase is what I should have put in the title. It's a 2001 mini mill. It has been running with 3 phase with the optional transformer. No one would say with any certainty weather it would run on single phase. I've since decided to take pass on it.

I am still looking but decided a mini mill 2 would be a better option with the 20 tool changer and additional Z height.

MiniMill2 is the best choice with the extra 4" everywhere it will run on 240v single phase also this needs to be the standard mill, none of the supper MiniMill's will run on single phase

[mejasont]

Haas's own documentation describes the connection of "Single Phase 240v" to the mini mill
In Operators Mini Mill Addendum ES0205l see attached pages

From this instruction i understand the UK single phase would be connected to Terminals L1 live and L3 neutral on the incoming Isolator

On transformer T5 the link will be set to match the incomming phase voltage so between 220v and 250v for our mains, (220v guaranteed 240v nominal) my supply is measured at 240v at the wall.

and finally check the tappings of the high voltage main transformer T1.

The confusion for me is my transformer is not in a metal case as per the manual and only has 2 plugs and not 4 or 5 voltage tappings - pictures attached

Id appreciate some feedback from anyone who can add some advice/confirmation on making this conversion

Thanks in advance

[mactec54]

Haas's own documentation describes the connection of "Single Phase 240v" to the mini mill
In Operators Mini Mill Addendum ES0205l see attached pages

From this instruction i understand the UK single phase would be connected to Terminals L1 live and L3 neutral on the incoming Isolator

Correct Plus Earth / Ground is required, you want a 60A Single Phase Supply

[mejasont]

Correct Plus Earth / Ground is required, you want a 60A Single Phase Supply

Hi Mactec

Thanks for your reply.

I had read that i needed a seperate earth cable ran and have planned to route it with the 6mm (8 SWG) SY Flexible cable back to a 40A type D MCB via a rotary isolator swich.
I beleive the seperate earth has to be connected to the main earth terminal back at the consumer unit.

The only thing im really having problems with
1. Trusting my machine is identical to any other mill - you cant rely on consumers not havig Haas additions/modifications installed - and
2. Which of the 2 connectors on the main transformer T1 should be connected to the incomming mains isolator in the electrical cabinet

The whole idea of only connecting to L1 and L3 goes against everything i know about electrical installations - i get that it will just appear as a missing phase at the main transformer (L2).

So for a quick test i should be ok to lift the connections from the main transformer and test the output and see it not exceeding 230v approx which will feed into vector drive or else its on the wrong tapping

Saying i think my machine is possibly different is down to it being a 2002 and the transformer T1 is not in a metal case with multiple voltage tappings (just 2 plugs).
The closest manual i could download from Haas (archive) was released in 2004 for the MM)

Im fairly confident/compitent working around electrical switchgear and distribution panels, I have worked in both the Royal Navy and Offshore, most stuff being 440v but some 3200v and 11kv for good measure.

The consensus is its straight forward and just to connect L1 & L3 to UK mains
some forget to mention T5 and to ensure the output is only 24v, i feel another test comming on with lifted connections
and no one mentions the correct voltage tappings are set - to be fair its been wired to 220v 3 phase most of its life in the UK so highly unlikely to be tapped for anything else.
better to be safe than sorry.

Its a 6k spindle and no TSC (spindle coolant, its motor would be 3 phase only) requiring a vfd and a contact to enable it

Asked my HFO last week to call, still waiting, its because its an old machine and they wont make much money isnt it. If I was haas id be over the moon that i built a product that i could say was so reliable that it lasts nmore than 18 years - what a selling point.
+ its the UK all talk and no action. lol.

Thanks
Jason

[mejasont]

Sorry yes i have a 60A supply, actually its a 100A fused incomming supply but im sure they dont want me to peek that. lol.
All this because i cant get 3 phase yet, the building trade has hammered the whole UK connection services to a point you have to wait months for a supply and then months to get a meter from a service supplier.

[Al_The_Man]

Do you have any schematics or any available.
I notice the photo's show a fairly large 440v 3ph transformer?

[mejasont]

Do you have any schematics or any available.
I notice the photo's show a fairly large 440v 3ph transformer?

This is about as good as it gets, but im still delving into it to be fair
J.

[mejasont]

Ok be wise and be careful, my conversion didnt quite go to plan. It is as straightforward as it sounds provided you dont have a vector drive - vector drive not possible apparently.
If your mini mill /vf0 to vf2 and TMs can be switched, if the machine has the 320v dc psu and the spindle is driven from a seperate servo (vector drives run the spindle as well as produce the 320v dc)
The 320v dc transformer accepts 220v ac input wired between the outer 2 phases i have the terminal style psu so terminals 2,3,and 4 are L1 l2 and l3. so from the mains incoming supply only L1 and l2 are used by wiring Live to L2 and neutral to L3 below the contactor relay where the L2 wire goes down to the transformer - disconnect it all together. remove the big transformer T1 which sits right at the bottom of the cabinet. it normally converts 415v (220v between 2 phases) to 115v 3 phase phase which connects to the 320vdc PSU - that makes sense as betwen l1 and L3 would measure 220v when the machine was connected to a 3 phase 220v supply. T5 the 24vac transformer which provides power to the power distribution board for the power on/off circuit on the panel. some of the transformers are built to only output 24vac from 440v between incomming phases and will only produce 12v. this transformer therefore would need changed to go across L1 and L3 to produce 24vac from the 220v across L &N on L1 & L3. what i didnt spot was the main transformer T1 has an extra tapping which provided 115vac to the rest of the machines instruments - also wired back up to the power distribution board. making this mistake mad my IO/main control board go bang. 16k down the swany. was ok i repaired the board saving £1200 + the call out charges. Was very close to throwing the towel in at that point, curling up my toes, kicking the can etc. on the power distribution board there is also a connection for 220vac, in my case this was already wired to L1 and L3 of the incoming supply (at the PSU terminals) so it went from 220v, 115v between phases to 220v directly wired to L & N via L1 and L3. The people who have had an easy time doing the conversion will have had machines which displayed 3/1 for phase on the machine ID plate, mine just said 3. if your mad enough to try your mad enough to throw it all away - this is not for the faint hearted. When i powered my machine up the display was blank, that sinking feeling of a dead CPU filled me with dread. turns out 17yr old CRT displays are crap and die during transport, i planned to do an LCD conversion so i just brought my plan forward. Its pure nectar when you power up and the machine starts to blurt out information. you know you have cracked it when you get a massive list of alarms - shows the processor is working. Hard to produce a video output and display information from a dead micro. The jog wheel flashed up an alarm for reasons unknown. I buzzed through the keyboard pcb harness for the jog wheel which goes back to the Mocon board. Didnt find anything but when i reinstalled it and powered up agin magic happened, alarm had gone away. Ill say one thing haas are stupidly expensive but their machines are bullet proof. My final word of advice would be "dont try this at home kids" The current quote for the HFO to do the conversion is £2500, just saying.