Recommended external switches for 3phase motor/VFD combo?

[dmelton]

I just took delivery of my new grinder motor from dealers industrial. I've asked them this question and have not heard back yet so I figured I'd ask here. I ordered the following combo: http://dealerselectric.com/2HP-3600RPM-230Volts-Input-Package.asp

I want to mount the VFD in an external enclosure mounted on the side of my grinder table and have a remotely mounted on/off switch with a speed potentiometer. Anyone have any recommendations on a specific switch combo that would do this? Thanks!

 

[Drew Riley]

I don't know about switch combos, but I believe most makers just mount the components inside a standard switch box. You can get a blank plate and position them how you wish.

 

[Stacy E. Apelt - Bladesmith]

The ON/OFF switch on the VFD, and the remote ( there should be places for a remote on the board) are not carrying much current. A simple SPST or DPDT-center off toggle switch is all you need. Get a 10 amp rated switch, but that isn't really an issue.

 

[dmelton]

Thanks. I wasn't sure if the switches had to be something special.

 

[Ken H>]

Nothing special and it's typically a 10K pot required for the speed control.

 

[12345678910]

Ar you making your own wheels ?

Do you see the shaft size on that motor ?

 

[dmelton]

Yeah, it's a 7/8 shaft. I got a 7/8 4 inch crowned drive wheel from knife grinder parts dot com. That guy has GOOD stuff, not the cheapest but the quality is high.

 

[dmelton]

Ordered this pot http://www.amazon.com/potentiometer-potential-black-control-Knob/dp/B009QFU9H4/

I'll use a standard light switch for on/off.

 

[Stacy E. Apelt - Bladesmith]

A regular light switch is far too large in size for the task. Use a toggle switch.

Here is what you want if it is just ON/OFF:
http://www.ebay.com/itm/Heavy-Duty-...ash=item235db12717:g:LHEAAOSwbdpWU8KK&vxp=mtr

for forward/off/reverse use this one:
http://www.ebay.com/itm/Heavy-Duty-...ash=item19f0414892:g:2pcAAOSwPhdVTM0j&vxp=mtr

NOTE:You can buy five of these type switches for about the price of two, so if you think the extras will get used, buy the multiple groups.

 

[dmelton]

Thanks!!

Let me ask a question. What would be the use in reversing a belt on a grinder? I've seen several folks with reverse switches on their DIY grinder. I've not experienced a need to do that yet... Seems like a good way to get a face full of sparks. =)

 

[Drew Riley]

Thanks!!

Let me ask a question. What would be the use in reversing a belt on a grinder? I've seen several folks with reverse switches on their DIY grinder. I've not experienced a need to do that yet... Seems like a good way to get a face full of sparks. =)

It CAN be useful for sharpening, but it's really not necessary; besides, your tracking will likely skew one way or the other, and a backwards running belt is really hard to correct with just a tracking knob/wheel adjustment. What would be most useful though, is if you were to build a disk grinder in the future, those benefit from being able to reverse. If you put a plug on your VFD, you can use it to switch between machines.

 

[Stacy E. Apelt - Bladesmith]

If you build it in, forward/reverse can be used on other devices run by the VFD. Disc grinders, dedicated sharpening machines, as well as mills, etc. can all be run backward to great advantage in certain circumstances.