Thread: Milling machine

Think of the VFD as a variable speed contoller for 3-phase motors that runs off a single phase supply.
In addition to that function it can - but you don't have to use - a lot more tricks: soft start, controlled decelleration, change direction, set constant torque, be controlled from a computer or other digital device, have a remote control and many others.
Go get the MM and the VFD - you won't look back!
Joe

Originally Posted by jhovel

Think of the VFD as a variable speed contoller for 3-phase motors that runs off a single phase supply.
In addition to that function it can - but you don't have to use - a lot more tricks: soft start, controlled decelleration, change direction, set constant torque, be controlled from a computer or other digital device, have a remote control and many others.
Go get the MM and the VFD - you won't look back!
Joe

Thanks for the tip. Looks like ill go that way. What do I need to look out for to make sure i get a vfd thats compatible? If the mill is 2 hp do I just get a 2hp vfd?

Yep, that's if as far as the VFD is concerned.
However (there is always one), the low end VFDs can only output the Voltage of your supply. In other words, it will output will be 240V 3-phase.
Your 3-phase motor needs to be wired in "delta" (coils in triangular connection shape without a connection to a neutral centre point). For 415V supply they are usually wired in Y or star configuration. Many 3-phase motors have those two options in their junction box, usually labelled in the junction box lid. If yours doesn't, you may need to take it to a motor rewiring shop and ask them to "split the windings". They find the central connection point of the three coils and solder on separate leads to connect them in delta. I found they do that cheaply. In one case they offered me another used motor that came with all 6 terminals instead, for a nominal figure and kept mine....
Cheers,
Joe

Thanks for the help. I guess ill buy it and see what happens.

I got the specs for the machine today. Im still not sure if i should run the vfd or fit a single phase motor. Does the vfd just plug into a power point or does it have to be wired into the mains?

Also not sure if the vfd or motor im looking at will work.
the specs are
Class: E
HP: 2
Poles: 4
Temp Rise: 60°C
Volts: 415
RPM: 1420
Amps: 3
Cycles: 50Hz
Toyang 3phase Induction Motor


The motor im looking at is this one:
http://www.ebay.com.au/itm/BRAND-NEW-2HP-240v-Electric-Single-Phase-Motor-/390329230743?pt=AU_Power_Tools&hash=item5ae16f6597


and the vfd is this one:
http://www.ebay.com.au/itm/VARIABLE-FREQUENCY-DRIVE-INVERTER-VFD-NEW-2HP-1-5KW-7A-/290540865401?pt=AU_B_I_Electrical_Test_Equipment&hash=item43a595c779


Any advice?

I guess it's your call.
Have you actually seen the 3-phase motor ID plate?
Many motors say "240/415V AC" but the final decision if the motor is easyly chnged to Delta wiring is made by looking at the connection termunals: of there are 6 connectors with 3 brdges, then its a 30 secind job, if only 3 connectors, a trip top the local motor rewinders is in order.

The VFD you chose is a Huangyang. Here is manual for it (on case the vendor doesn't send it).

The motor you se,ected is a two-pole motor running at 2830rpm - twice the speed of the original. You will have to change your drive pulleys to half the diameter to compensate!

Joe

Ok I get ya. The specs I wrote were off the motor plate but I didnt view it myself. Im waiting for some pics though.

I can change pulleys easy enough. Would that motor be ok based on the rest of the specs? Im leaning more towards the motor swap as I dont really know anything about vfds lol

Sounds OK to me. I suspect you will kick yourself down the track for not going with the VFD though
I just love being able to turn my spindle speed down to 1/2rpm for settting up tricky work....
Joe

I haven't ruled out the vfd. Just don't know much about them. My big issue is if it just plugs into a PowerPoint or if I have to have it wired to the mains. I'm planning on selling soon so I don't wanna do anything permanent. If it just plugs into a PowerPoint I will prob buy one

No problem plugging a 1.5kW VFD into a powerpoint. Just fit a flexible cable with plug on the end.
Joe