3 phase electrical "box"?

[Jeff Ramsey]

3 phase power feeds the box in the following picture, which then feeds the 3 phase motor. Any idea what the purpose of this box is?

362248

[Mike Kreinhop]

With "Furnas" on the box, my guess it is the motor starter or contactor. There should be another cable going into the box to energize the contactor, or some start and stop buttons on the box.

[Jeff Ramsey]

I was going to bypass it with a VFD and go directly to the motor from the VFD.

[Bill Dufour]

You need to open it up and see what is in there. It may be used as just a junction box but with a reset button I think it is some kind of overload or contactor, or both. You do not want any disconnects between the vfd and motor. If they trip off the vfd may overload and fry itself.
Bill D

[Darcy Warner]

It's a starter. Set up with remote start/stop station

[Mike Cutler]

Starter box
Are there any cable markings on the white cable?
Reason that I ask is that Rockbestos Pyrotrol is the same color. Depending on the date of manufacture, it can contain asbestos.

[Jeff Ramsey]

It's a 1976 Powermatic 30 disc/belt sander. Thanks for the asbestos heads up. Is there any way I could tell for certain?

The VFC connected directly to the 3P motor runs the motor. I just need to configure the VFD so the output Hz is capped at 60 and not 50, which is how's it's configured now.

[Darcy Warner]

Looks like some type of SO cable with white paint on it.

[Mike Cutler]

It's a 1976 Powermatic 30 disc/belt sander. Thanks for the asbestos heads up. Is there any way I could tell for certain?

The VFC connected directly to the 3P motor runs the motor. I just need to configure the VFD so the output Hz is capped at 60 and not 50, which is how's it's configured now.


Jeff

If there are any markings on the cable look for the date stamp. It would also be stamped with Rockbestos Pyrotrol II. It was a 90deg. C rated cable. 1976 is late for that type of cable. Manufacture of asbestos insulated cable ceased about 1972. The cable was redesigned after that.
Cross section of the cable will be a white outer jacket, with a black core. The conductors will be wrapped in paper, or foil, and the insulation will be between the conductors and the paper jacket.
It's the color that set me off, and the color of the individual conductors. I see a lot of this cable on a daily basis.

[Jeff Ramsey]

Can the 3P starter and switch be used for a single phase 220v input to a VFD? If yes, how would I wire it to the 220v input to the VFD? Starter looks like:

362644

[Malcolm McLeod]

I'd toss the starter. All of it's functions (on/off and overload protection) are replicated in the VFD. :: K.I.S.S.

If the machine does have a conveniently located operator station, you can re-wire the start/stop buttons to the VFD using its internal 24Vdc power, and use them instead of the VFD's on-board buttons.

[Darcy Warner]

I wouldn't toss it. That's a nice starter that some one could use.

[Malcolm McLeod]

:o:oOK, OK!! Do not toss it.:o:o

I'd remove and re-purpose the vintage classic starter in a socially, economically, and environmentally responsible manner.;)

[Mike Schuch]

A three phase motor controller can easily be re-purposed as a single phase motor controller by simply only using 2 of the three legs (You have to choose the two legs that power the contactor coil). I have many old single phase machines with three phase motor controllers on them. The three phase controllers can be picked up off of ebay for cheap and they are MUCH higher quality than those plastic single phase contactors that come on new machines. If you are worried about motor protection you should replace the heaters in the motor starter to match the motor you are controlling... I have never worried about this.

Are you going to unplug your new VFD when you are done using it or are you going to put a switch in front of it to power off the vfd when you are done with the tool for the day? I didn't put switches in front of my vfd's so I just pull the plug when I am done. The fan on the VFD's are loud enough that they remind me something is running when I leave the shop in the evening.