Spindle motor upgrade & VFD - who sells this stuff?

[turbostang]

I just recently bought a Series I with a Centriod control system on it. I want to upgrade the motor and ad a VFD to it in order to be able to use single phase power and have programmable spindle speed.

Does anyone sell a "kit" for a series one that is a pretty straight foward install? Does the motor need to be changed?

Does the motor just need a pulley that matches the spindle pulley in order to get the 1:1 and let the VFD take over?

[mxtras]

You can do pretty much everything you are looking to do by the simple addition of a VFD. No need to change the motor.

Check www.driveswarehouse.com. There are many other places - maybe others will chime in and help locate some killer deals on VFDs.

****edit***** I just realized that you are likely asking for details of how to integrate into the original machine control system. I can't help you there. Sorry.

Scott

[turbostang]

Scott,

The way I understand it, the machine is already capable of interfacing with the VFD. I was not sure on whether or not I needd a new motor or anything else.

I should still need a replacement pully though, correct?

[Al_The_Man]

If it already has a 3 phase motor, see what the name plate rpm is, if it is ~1700 then it is a 4 pole motor and can usually be run up to 120hz effectively doubling the rpm. If ~ 3500 then it is a 2 pole motor and normally not recommended to go over this unless a vector rated motor is fitted.
For the control, ideally you will need analogue spindle output from the controller the level of which is controlled by the S value, this also means you must have a way, either in the controller (parameter) or VFD for scaling this signal to correspond with the S value.
Al.l

[mxtras]

Al -

Are there concerns of overheating?

Sorry for the minor hijack but this seems relevant to the thread....

Scott

[Al_The_Man]

You mean at low rpm? Possibly, but You would have to run at prolonged low speed at high current I would think.
The knee mills I have that I converted I use in this manner, although they are fortunately fitted with a two speed gear box, I removed the Vari-drive belt in favour of 1:1,
For the low speeds, I use the 6:1 gear ratio.
Al.

[turbostang]

Originally Posted by Al_The_Man If it already has a 3 phase motor, see what the name plate rpm is, if it is ~1700 then it is a 4 pole motor and can usually be run up to 120hz effectively doubling the rpm. If ~ 3500 then it is a 2 pole motor and normally not recommended to go over this unless a vector rated motor is fitted. For the control, ideally you will need analogue spindle output from the controller the level of which is controlled by the S value, this also means you must have a way, either in the controller (parameter) or VFD for scaling this signal to correspond with the S value. Al.l

It's definately a 3 phase motor. I am also pretty sure it's a 1700 RPM as well.
The controller supposedly already has the correct outputs inplace to work with a VFD. As for setting it up, I am not totally sure how that will work. It would be nice to not have to get a phase converter or the likes.

Originally Posted by Al_The_Man You mean at low rpm? Possibly, but You would have to run at prolonged low speed at high current I would think. The knee mills I have that I converted I use in this manner, although they are fortunately fitted with a two speed gear box, I removed the Vari-drive belt in favour of 1:1, For the low speeds, I use the 6:1 gear ratio. Al.

It has the 2 speed head and the vari-drive setup now.

How hard of a job is installing the VFD and getting it setup?

[Al_The_Man]

You wire two phase in - three phase out to the motor, 2 wire ±10v Analogue from controller to the VFD, Ideally you also need two output signals from the VFD for Zero speed and Up-to-speed to the controller.
Some rudimentary electrical/electronics knowledge is a help.
For tuning the VFD, it helps if you get one with the self tuning option.
I have not done one on a bridgeport, the ones I have are Excello, but the principle is the same.
Al.

[turbostang]

Originally Posted by Al_The_Man You wire two phase in - three phase out to the motor, 2 wire ±10v Analogue from controller to the VFD, Ideally you also need two output signals from the VFD for Zero speed and Up-to-speed to the controller. Some rudimentary electrical/electronics knowledge is a help. For tuning the VFD, it helps if you get one with the self tuning option. I have not done one on a bridgeport, the ones I have are Excello, but the principle is the same. Al.

There isn't any need to run a bigger VFD than what the motor rating is, is there? (like to be able to handle the starting load of the motor)

[Al_The_Man]

Some manufacturers will suggest a de-rating factor, I have used the Mitsubishi 1.5kw for 2hp motors for some time and not had a problem, the VFD also controls the accel/decel so the the inrush is different than starting a motor across the line, the VFD parameters limit things like maximum current etc, DC braking etc.
Al.

[turbostang]

Thanks Al!

I am stuck on wheter or not I need to get the VFD now or get a 3 phase rotory converter - if I do the later, I can get a "bigger" converter and use it for my lathe if it's a 3 phase. If I don't get a rotory phase converter now, I'll have to limit my lathe search to 220V single phase, or heaven forbid 110V.

[protman16]

turbostang,

You might want to consider a VFD over a rotory phase converter. Reason is most VFD's can run off single phase. The plus is what ever 3ph motor you want to control will also have variable speed. That way you won't need to change belts or gears as often when serching for that perfect cutting speed.

Trevor