1. Colchester Lathe Triumph 2000

I am about to take delivery of an old Colchester student lathe. It is wired for three phase at the moment. I dont have a three phase supply in my garage so i wondered if anyone had any ideas as to my best/cheapest option? The lathe motor is dual voltage 415/240 and 3hp and the coolant pump motor is also three phase. I would prefer to keep the lathe as it is ie using its gears for speed controls and the original on off controls. I have no real knowledge of electrical wiring, But i do have an electrician friend who would carry out the techy bit for me. My first thought was if the motor is 415/240.

Could this be wired to the 240v supply in my garage providing it was upgraded to take the size of motor? Second thought was to purchase a 240 volt 3hp motor and 240v pump? Lastly i would conceder an inverter or some other method of converting the single phase supply in my garage to three phase? I would welcome any help with this, and be really grateful if it was put in a way a numpty like me cold understand. Many thanks in advance. Any options involving rewiring the controls are off the table, so that removes any VFD options.

Running two motors off one VFD is not a good idea, so that also removes the 'one VFD' option. The 'replace the motors' option can get a bit clumsy, if unusual motor frames are involved. I suggest you research rotary phase converters, or perhaps Phase Perfect, a type of VFD that tolerates motors being turned on, turned off, multiple motors, etc.

Most likely, a rotary phase converter, AND rewiring the lathe motor's to 240 volts. I have now had a look on the web and i think i am right in saying that the 240v side of the dual voltage motor is for wiring in some sort of VDF/ Inverter? And not an option for just connecting 240v from the mains supply? So it looks like that option is out the window. I am thinking i could make a reasonable job of changing both motors for 240v and still keep thing neat. My worry there would be. Could i keep the original switches?

Colchester Lathe Triumph 2000

Or would they have to be modified for the new voltage? I have no idea at the moment what a rotary phase converter is. And the same goes for Phase perfect. So i will have to look that up to see if it is an option for me. Many tanks for the prompt reply. Your initial post made sense, but the 2nd post is a bit confusing. Were both posts written by the same person?

You need three phase electricity to supply two motors. AND you don't care to modify the lathe's wiring any more than needed. Is the lathe currently set up for 240 volts of three phase? In that case, you can avoid any wiring changes. If the higher voltage is indicated, you can use a transformer to avoid changing the lathe's configuation.

(But you don't have the skillset to rewire the lathe, which means you don't have the skillset to install a transformer.) If the lathe is 240 volts, three phase, then investigate the ways to create three phase 240 volts, BUT NOT VFDs, VFDs demand one to a motor, and no switches between the VFD and the motor. You have three options, barely: A static converter (not the best option) A rotary converter, tried and true. An electronic converter, sometimes called 'inverter', which is a purpose built variant of VFDs, more robust, more resilent, thereby allowing multiple motors, starting and stopping motors, etc. In the States, a popular trade name is 'Phase Perfect'. Pete, About 20 years ago I got a 13' Clausing Colchester lathe.

I think it is very similar to the 'Student' model. Mine was wired for 240v 3 phase. You should check yours and if necessary rewire to 240v. Your electrician friend can handle that.

I wouldn't try to change any motors on the lathe. Your next choice is phase conversion. A rotary converter will work. If you plan on other 3 ph equipment this may be a good choice. The output of the converter wires directly to the machine.

Do not use a typical static converter. It will definitly choke on the the 2 speed motor. The only type of static that will work is an autotransformer or Phase Perfect.

Both very expensive options unless you can build your own autotransformer converter, probably not an option in your case. I setup mine to use a VFD wired between the start handle and the internal 3 ph wiring. You turn the VFD on with the lathe On/Off handle and control it with a remote control box mounted on the lathe. All the original machine controls are still usable, speeds, gearing etc. You also have the variable speed feature of the VFD. You list your motor as dual voltage.

Is it also a 2 speed motor? My colchester 13' lathe, 1968 vintage, has a 2 speed Brook Compton motor. If you insist on no rewiring then you only have one practical choice. Get a Rotary Phase converter as already suggested.

If you have a single speed motor, then could consider a VFD (variable frequency drive). Cormidi 60 operating guide. You would need one for the main motor and one for the coolant pump. The amount of rewiring will be a few hours but not days.

If you have the electrical diagrams, show them to your electrician and see what he thinks. Your initial post made sense, but the 2nd post is a bit confusing. Were both posts written by the same person? You need three phase electricity to supply two motors. AND you don't care to modify the lathe's wiring any more than needed. Is the lathe currently set up for 240 volts of three phase?

In that case, you can avoid any wiring changes. If the higher voltage is indicated, you can use a transformer to avoid changing the lathe's configuation.

(But you don't have the skillset to rewire the lathe, which means you don't have the skillset to install a transformer.) If the lathe is 240 volts, three phase, then investigate the ways to create three phase 240 volts, BUT NOT VFDs, VFDs demand one to a motor, and no switches between the VFD and the motor. You have three options, barely: A static converter (not the best option) A rotary converter, tried and true. An electronic converter, sometimes called 'inverter', which is a purpose built variant of VFDs, more robust, more resilent, thereby allowing multiple motors, starting and stopping motors, etc. In the States, a popular trade name is 'Phase Perfect'I was looking for options. I have very little electrical knowledge.

I firstly thought that i could wire the lathe to the 240/415 motor by connecting to the 240v straight to the motor from the 240v supply in my garage. I see now this is not the case. I dont want to have an outside switch with variable speed really, I would rather have the gears on the lathe and the lathes own on/off switch.

So i would think a phase converter is not an option either But i am not sure. So to me it is looking like the only option is to change both motors for 240v single phase and try to make the neatest job of it i can The motor on the lathe at present is wired directly to 415v 3 phase supply If i could keep this motor, all to the good But i dont want to use it if it means a separate on/off button and all that goes with it. If i change the motors for 240v single phase ones would i have to make changes to the switches? Or will they work on 240 single phase? Sorry for my lack of knowledge.

And poor description. You list your motor as dual voltage.

Is it also a 2 speed motor? My colchester 13' lathe, 1968 vintage, has a 2 speed Brook Compton motor. If you insist on no rewiring then you only have one practical choice. Get a Rotary Phase converter as already suggested. If you have a single speed motor, then could consider a VFD (variable frequency drive). You would need one for the main motor and one for the coolant pump.

The amount of rewiring will be a few hours but not days. If you have the electrical diagrams, show them to your electrician and see what he thinks.The lathe in question is a square type with the speed controlled by two rotary handles that have to line up with differing coloured quadrants to select the speed you need, all it has on it is Colchester student 1800.

I am not sure if the motor is a two speed one. I only noticed 240/415 on the plate And did not check the speed. I will be visiting the place the lathe is located on Wednesday so i can get more info then. I am not so worried about rewiring, Its more that i want to keep the original switches on the machine and not have a box with a separate switch and speed control on it. I just want it to run as it stands now. But on the voltage i can supply from my garage. Whatever form that may take.

Hi, this is my first post and am brand new to metal lathe work. I have put down a deposit on a Colchester Student which has already been converted to single phase. Two things that dont work on it are Reverse, and the coolant pump. Can anyone offer any advice please, I intent to strip it down and clean it up a bit as it needs some TLC. Thanks Dai PS I have just purchased a manual and parts list if anyone needs a copy.Sounds like it hasn't been converted to single phase but rather just had a single phase motor put on it.

Hence why the coolant pump doesn't work (pump is 3ph.) nor the reverse. Reversing a single phase motor requires switching the leads to the start winding so the motor starts in the desired direction. If the motor doesn't reverse from stationary, the lathe has simply had the motor replaced.