cnc and 3 ph issues, fadal

Just got off the phone with Fadal.
Turns out that if running a 3016L off a rotary converter, there is no easy
way to separate the electronic stuff from motor stuff, ie, no easy way to
put the electronic stuff on 220/240 single phase, and have the wild leg just
go to motors. This is because, from the schematic, all three legs go all
over the place.
The transformer is a 3 ph transformer. T-820.
There are *un*easy ways, however.
One is, just leave the machine underpowered, ie, set the jumps for the wild
leg voltage, with the other two phases thusly underpowered. It seems that
one of my symptoms, machine shutdown on 3-axis 100% rapids, is explained by
being underpowered.
So yeah, both easy and uneasy.
Another possibility is to perhaps set ONE of the jumps to accommodate the
wild leg, ie, not all three jumps the same. The tech hem-hawed at this.
Any idears on this? This would be great, if do-able.
Another he said is to take the three legs going to an amplifier, and the
three legs going to the spindle inverter, disconnect the "wild leg output",
and just jumper over one of the other legs to the amplifiers/inverter, as
they just need three hots, apparently, not necessarily three different
Sounds a little weird to me. I can see it more for the amplifers, if they
are just 110 V, but the inverter seems a little less straightforward, if
it's 3 wire 220.
Another is to get separate transformers. The tech said people have done
this, but fadal has no schematics on how this is done, as they don't support
I'd like to know how this is done.
Another is to get the T-812 transformer, for single phase input. About
$1200, but also available on Ebay, he said, altho it's not on ebay as of
Inyone got a T-812 sitting on a shelf??
Another is to find some goddamm way of toning down the wild leg. Possible
with the voltage stabilizers I mentioned in Ping Clay ("buck boost"
transformers). Tech said these were OK, but not the greatest either. I'd
like to know how these work.
I think I'm going to email fadal regarding "fine-tuned" jumper settings, see
what they say.
Reply to
Proctologically Violated®©
Loading thread data ...
Another is to find some goddamm way of toning down the wild leg. Possible
I think this is your besat solution. It may require a different idler motor, if you have already tried the run caps from generated leg to both of the supply legs. Or, maybe you just need more run capacitor value. I think Fitch Williams put out some really good info on how to do this some years back.
Reply to
Jon Elson
Yeah, I gotta look this up. Iny links?
My understanding is the caps are already between L3 (wild) and either L1 or L2. Are you saying to put caps from L3 to *both* L1 and L2?
My understanding is that these caps are just for startup, and that some recommend relaying them out after startup. I'll proly have to physically experiment with all of this. Gonna take forever....
Reply to
Proctologically Violated®©
Received a hot tip from an electronics guru. Putting the hot leg in the center of the 3 the incoming taps, and on the drives, cured most of my servo problems. Although, I still couldn't go from 0 to 8K without a spindle alarm. Had to step it up in 1500rpm increments.
Remember moving into my first industrial unit with real 3ph. From 0 to 12k.......then kick it in reverse.......because I could!
Reply to
Matt Stawicki
I have done that also with real 3ph, on my OTC's & OTD's & my haas, the fanuc's didn't like it any other way, but then my 3ph is 240-245 volts.Been running that way for 15 yrs on my Hardinge. When I bought the Hardinge new in 92 $68K I told them the 240-245 voltage & Hardinge said don't worry about it. Yep $68K but they did give me $15K for my old AB Hardinge & shipping, damn in 92 dollars that was a lot but my AB control was crapping every month & costs about $1,500 every time.
Reply to

PolyTech Forum website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.