Thread: Speed control alternative to VFD??

I have a 3ph waldown Grinder 8", the Colchester lathe 3ph, and will have the motor from Ueee

Yes, but you will soon get tired of screwing wires onto terminals and the alternative (3 phase plugs) are not cheap. I think one of Joe's cheap VFDs would cost less than a plug and socket pair...

Michael

Originally Posted by DSEL74

Ok here is another random question can you set a vfd so that you can use it for more than one machine? One at a time of course.

You could but it would be a right PITA.
Each machine has different motors and uses and to get the optimum use out of it the VFD has to be preprogrammed.

EG my
DP; 4 pole motor, fast acceleration and deceleration, max freq, 120Hz.
MW lathe; 4 pole motor medium acceleration and deceleration, max freq, 70Hz.
Linisher; 2 pole motor, slow acceleration (aid check of belt alignment) and medium deceleration, max freq, 60Hz.
Grinder; 2 pole motor, medium acceleration and deceleration, max freq, 60Hz.
WW lathe; 4 pole motor, fast acceleration and deceleration, max frequency 100 Hz
Compressor; 2 pole motor; slow acceleration, max frequency 50Hz.

The waldown & Colchester both have plugs. although very different sized motors. "Joe's cheap vfd"???

Originally Posted by DSEL74

The waldown & Colchester both have plugs. although very different sized motors. "Joe's cheap vfd"???

Joe Hovel. These VFDs have an issue that need sorting out if they are going to be used on grinders.

So what do I need to look for in a vfd for this?

Originally Posted by DSEL74

Ok here is another random question can you set a vfd so that you can use it for more than one machine? One at a time of course.

Yes, been there, done that, unlikely to do it again*
As Micheal says, given the current price of VSDs its pretty much a waste of time. Even a cheap "normal" 3 phase socket is going to be about $30, plugs $20. so you're up for $70. Then it depends on what you want to do re controls, though with a couple of grinders I guess you wont be needing much.


*given the cost of the plugs below I might rethink that

I figured there must be some cheaper plug/sockets about. But if you're still keen, how about these?
http://www.ebay.com.au/itm/16A-AC-44...item5d4def5f61

http://www.ebay.com.au/itm/Brick-Red...item4d206c333f

http://www.ebay.com.au/itm/16A-AC-44...item4623299470

http://www.ebay.com.au/itm/16A-AC-44...item46232a3c9d

Or is the world going to end if I was to use these?

Stuart

World going to end or just the shed burn down???????????

One of these VFD's is what i would use. http://www.ebay.com.au/itm/3HP-2-2KW...item1c3984881e

Just remember they are not sealed so you need to be careful on a knife grinder, your likely to have water flicked around as you keep the blade cool. One of the ABF members cooked his VFD the other day by getting water in it from off the blade after cooling.

I'll be sure to put the motor in the car.

Ew

Thanks Ew.

Originally Posted by Stustoys

I figured there must be some cheaper plug/sockets about. But if you're still keen, how about these?
http://www.ebay.com.au/itm/Brick-Red...item4d206c333f

Watch out - I bought a pair of these and they are potentially VERY dangerous. The plug/socket arrangement is not different enough to prevent the earth pin from being pushed into and making contact any one of the phases. The plug won't go in all the way but the earth pin can still make a contact with a phase.

http://www.ebay.com.au/itm/NEW-IP66-...item566a77b280 Buy one of these, wire it up and move on. If you think $80 is too expensive, visit a scrap dealer or 2 (or get another hobby). I have a large box full of 3 phase switchgear I got off a scrap dealer for cheap, enough for 2 lifetimes (I hope). PDW

Originally Posted by Stustoys

Yes, been there, done that, unlikely to do it again*
As Micheal says, given the current price of VSDs its pretty much a waste of time. Even a cheap "normal" 3 phase socket is going to be about $30, plugs $20. so you're up for $70. Then it depends on what you want to do re controls, though with a couple of grinders I guess you wont be needing much.


*given the cost of the plugs below I might rethink that

I figured there must be some cheaper plug/sockets about. But if you're still keen, how about these?
http://www.ebay.com.au/itm/16A-AC-44...item5d4def5f61

http://www.ebay.com.au/itm/Brick-Red...item4d206c333f

http://www.ebay.com.au/itm/16A-AC-44...item4623299470

http://www.ebay.com.au/itm/16A-AC-44...item46232a3c9d

Or is the world going to end if I was to use these?

Stuart

Stuart, I have been using for all my VFD enclosures C16-1 connectors, either from Amphenol or Hirschmann. They are good quality, yet very affordable, safe, IP67 weather proof, and captive so cannot vibrate loose. Davey pumps used to fit these to there household pump pressure controllers which were installed outdoors, so there should be no issue using them in Australia.

The 3P+E I use for the motor, the contacts are rated 14A and 400VAC. Use the female panel socket for the VFD enclosure, and the male plug for the cable to the motor.
The 7pin plug I use for the control line (start/stop/reverse, emergency stop, and speed pot), these smaller contacts are rated 10A and 250V. Use the female panel plug for the VFD enclosure, and the male plug for the machine.

Most suppliers like RS or Farnell have these. Radio Parts in Melbourne sell them for a very good price: http://www.radioparts.com.au/categor...s/power-signal
Can also be found on ebay:
http://www.ebay.com.au/itm/Chassis-S...item48614475d7
http://www.ebay.com.au/itm/Line-Plug...item486144524b

If one uses the same connectors and the same pinout for all machines and all VFD's one owns, the items become functionally interchangeable. Good in an emergency, or to troubleshoot.

Here some examples how I have used these connectors between VFD and machines/motors:
02_DSCF0317.JPG
X3 mill VFD cabinet


03_DSCF0318.JPG
Waldown drill press


04_DSCF0319.JPG
Portable VFD (for small drill press)


20141001_131458.jpg
Hercus 260 (rear view)


01_DSCF0316.JPG
Emco Lathe VFD cabinet

Originally Posted by RayG

The http://www.jaycar.com.au/productView.asp?ID=KC5509 is the one you want for single phase induction motors...

Ray

Ray have you used this vfd? Single phase output inverters are not common from what I've seen, and this could be quite significant. I'm also often asked about single phase VFDs for other applications like pool pumps etc.

The article describing it can't be viewed on my ipad, so I'm curious as to what types of single phase motors it can be used on.

To the OP, while I'm a strong advocate for inverter drives, I think a vfd would be overkill in this application, especially if cost is a serious concern. I'd suggest a combination of pulleys would probably be sufficient to vary the speed in the ranges you'd need.

With regard using plugs and sockets, be aware that having unnecessary plugs and sockets is considered poor practice in the electrical world.