VF-2 Wiring Question...Where does manufactured leg from phase converter go?

[super95awd]

I, as well as the electrician and electrical engineer were assuming that the manufactured leg from the phase converter needs to run to the the L3 position on the machine breaker. Can anyone confirm this?

[Al_The_Man]

The main thing is is to ensure that the 1ph 240 pair feed the control and low voltage section, the 3rd leg would just supply the 3ph dependent items such as 3 ph motors etc.
Dependent on the machine, if the low voltage 1ph circuits is spread across the 3 phase, then they ideally should be swung over to the 240v 1 ph supply.
Al.

[super95awd]

Thanks for the response. That's what I was figuring. Maybe a Haas electrical genius can chime in and let us know which legs of the main breaker power the single phase stuff.

--Andrew

[Geof]

......which legs of the main breaker power the single phase stuff....-Andrew

I have wondered which legs supplied what. Possibly one way to find out is to use a clamp-on ammeter to measure the current in each leg when the machine is idle. I wonder if you could get one sensitive enough to show the difference when the only load was the internal low voltage power supplies.

Certainly it should be possible to find which legs supply the coolant pump and chip auger because these have a significant current draw.

Of course I guess this approach doesn't help if you do not have the machine powered up and want to know the answer before connecting it.

[Al_The_Man]

Hopefully you have the service manuals and schematics, if so this will tell you right away.
Al.

[haastec]

Hopefully you have the service manuals and schematics, if so this will tell you right away.
Al.

Haas!!! Provide an electrical schematic!?!

I have no real credibility for this other than it is handed down information from those more knowlegeable than me, but I have always been told to wire the "wild" leg so to speak to L2.

So with that, I have probably only confused the issue more.

[Al_The_Man]

Haas!!! Provide an electrical schematic!?!

Too bad, this would be one of my conditions on whether I buy the machine.

As a last resort it should not take an electrician or technician to do a little 'reverse engineering' of the panel wiring to discover the control circuit feed.
Al.

[haastec]

Actually, Haas does now provide some schematics on a CD included with the manual, but I don't think it is as detailed for what is being discussed here.

[Al_The_Man]

Must be very difficult to do any trouble shooting, or do Haas claim they will never go wrong?
Al.

[Machineit]

On my Haas, legs #1 and #3 are the legs that are used to provide power to the other areas. Therefore the wild leg is on #2.

On any machine you wire, CNC, Manual mills lathes etc., always avoid using the wild leg for activation on mag starters etc.. It may work for a while, but in the end it will usually end up burning out the coil in the mag starter.

To find the leg, just use a meter and check each leg to ground. One will be much higher and that is the wild leg. If you check leg to leg, then wild leg to other will be higher and normal leg to normal leg will be lower. Easier to check to ground though.

In my shop, I have all of my three phase outlets wired to have the wild leg in the same place on each outlet, just in case someone changes one around or plugs in a different portable machine.

Mike

[Machineit]

If you look inside your panel, you will see the main manual breaker. It will have the three main current wires going into it. You will also see three small red (on my machine) wires on the same incoming side. I believe these are for the small fuses that indicate if a leg has blown the fuse.

Below that manual breaker, is usually the main breaker that is engaged when you push the start button. On the outgoing side of that mag started will be the three main lines and two small lines, usually red and black. These are the power lines for the 120v circuits I believe. The one that does not have the small line, like I said #2 on mine, is where the wild or ghost leg goes. That leg will only be used for three phase items, which have no problem handling the extra voltage.

Mike

[Al_The_Man]

On any machine you wire, CNC, Manual mills lathes etc., always avoid using the wild leg for activation on mag starters etc.. It may work for a while, but in the end it will usually end up burning out the coil in the mag starter.
Mike

On items such as contactors and solenoids, I suspect the problems arise due to dips in the generated leg rather that high voltage, most 1ph AC magnetic devices can handle some over voltage with no problem, the stress comes with dips in the gen. leg when 3ph devices kick in.
This is one reason I spec in DC solenoids and use contactors with DC coils if possible.
The hysteresis curve on a DC magnetic device is much wider than that of AC devices such as these.
Al.