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Phase perfect to 480v transformer help needed .
I have a 30hp phase perfect that goes into a sub panel that feeds a haas vf2ssyt at 240v and it also feeds a 240-480v transformer that runs my haas st-10 lathe . when I have power going to the transformer the led lights in my vf2 will flicker a bit . if I turn on the st-10 the light will flicker in there too . not sure what is causing this . I checked the voltage between phases and all is good and I do not see any real fluctuation between phases . everything works fine on the lathe but the flickering light gets a bit annoying . here is a picture of the plate on the transformer .
Re: Phase perfect to 480v transformer help needed .
no idea on the flickering lights but how is the 480v secondary grounded?
it may not pass code but you can use some Y connected capacitors and ground the neutral point. you'll need 3 volt meters connected to an alarm so that when a ground fault occurs you will know it. resistors are also used for this type of situation, common on submarines and other mission critical systems where a single ground fault isn't a high enough priority to justify taking a system offline.
Re: Phase perfect to 480v transformer help needed .
I just have it grounded to the transformer case and then back to the panel .
Re: Phase perfect to 480v transformer help needed .
not clear to me what you mean. the 480v high voltage side of the transformer is delta connected. its floating relative to the transformer case, its not connected intrinsically to anything at all.
you can ground one of the phases which will stress the MOV's in your 480v equipment (if it has any) or you can make or buy a zig zag grounding transformer (ideal) or you can use Y connected capacitors (and or resistors) to ground it.
even just 3, 10uF capacitors should be sufficient, connected from each phase of the 480v delta coil to ground, if each phase to ground voltage is substantially different than 277 volts you have a problem
Re: Phase perfect to 480v transformer help needed .
Yes , it is just floating right now .I have the ground from the panel going to the ground lug on the transformer case and then to the ground on the cnc . I have been reading up on corner grounding but it does not sound ideal . do I need any special 10up caps ? do you have to add an extra ground rod to ground it or can I connect it to the ground from the panel ?
Re: Phase perfect to 480v transformer help needed .
Quote:
Originally Posted by
billwann
Yes , it is just floating right now .I have the ground from the panel going to the ground lug on the transformer case and then to the ground on the cnc . I have been reading up on corner grounding but it does not sound ideal . do I need any special 10up caps ? do you have to add an extra ground rod to ground it or can I connect it to the ground from the panel ?
Don't do this, if you are running both at the same time I would say that you have a supply problem, or your PP is right at it's max supply single phase supply
Does this happen when you only run the VF2 by its self or when both are running VF2 has an amp rating of 70 amps so you are right at the 80 amp rated on your PP for this one machine
Have you used the right size Ground conductor #7 AWG is the requirment
Re: Phase perfect to 480v transformer help needed .
Quote:
Originally Posted by
billwann
Yes , it is just floating right now .I have the ground from the panel going to the ground lug on the transformer case and then to the ground on the cnc . I have been reading up on corner grounding but it does not sound ideal . do I need any special 10up caps ? do you have to add an extra ground rod to ground it or can I connect it to the ground from the panel ?
You would ground the Y connected capacitors to the supply, the main panel, you need 480v rated capacitors.
There should be no current through the ground wire. But you need at a minimum 3 volt meters and or an amp meter; when a ground fault occurs on the 480v side the voltages will read 0, 480, 480 instead of 277 277 277, and the current through the ground wire from the 10uf capacitors will be on the order of3 amps, instead of zero. you could run that wire through a current transformer and use the output to trigger a disconnect, or you could install a GFCI 3 phase breaker after the 480v transformer.
the only way to meet the code though, is buy an expensive system to do exactly what i just underlined or find a zig zag grounding transformer, or corner ground.
Re: Phase perfect to 480v transformer help needed .
Is the lathe that hard to convert to 220?
Re: Phase perfect to 480v transformer help needed .
Quote:
Originally Posted by
mactec54
Don't do this, if you are running both at the same time I would say that you have a supply problem, or your PP is right at it's max supply single phase supply
Does this happen when you only run the VF2 by its self or when both are running VF2 has an amp rating of 70 amps so you are right at the 80 amp rated on your PP for this one machine
Have you used the right size Ground conductor #7 AWG is the requirment
the leds in the lathe will flicker with out having the vf2 on at all .I am only measuring 12 amps on each phase going into the lathe so its way below the capacity of the phase perfect . I have 6 awg for a ground wire all the way back to the main panel .
Re: Phase perfect to 480v transformer help needed .
Quote:
Originally Posted by
billwann
the leds in the lathe will flicker with out having the vf2 on at all .I am only measuring 12 amps on each phase going into the lathe so its way below the capacity of the phase perfect . I have 6 awg for a ground wire all the way back to the main panel .
What is your supply this is where the problem is how many amps is the supply for the PP and what size are your cables that feed it
Re: Phase perfect to 480v transformer help needed .
Quote:
Originally Posted by
billwann
the leds in the lathe will flicker with out having the vf2 on at all .I am only measuring 12 amps on each phase going into the lathe so its way below the capacity of the phase perfect . I have 6 awg for a ground wire all the way back to the main panel .
what makes you think the power is actually fluctuating? leds are often driven with crappy drivers. some have a hold up time as long as half a second so to actually get them to flicker requires a complete power loss for anything from several cycles to a few dozen, or more cycles.
the led drivers that have no holdup time at all will flicker with power fluctuations, but its also those same led drivers (with no holdup time, no capacitor to store a charge) that are often crap.
Re: Phase perfect to 480v transformer help needed .
Quote:
I have a 30hp phase perfect that goes into a sub panel that feeds a haas vf2ssyt at 240v and it also feeds a 240-480v transformer that runs my haas st-10 lathe . when I have power going to the transformer the led lights in my vf2 will flicker a bit . if I turn on the st-10 the light will flicker in there too . not sure what is causing this . I checked the voltage between phases and all is good and I do not see any real fluctuation between phases . everything works fine on the lathe but the flickering light gets a bit annoying . here is a picture of the plate on the transformer .
I'm having the exact same problem on my VF-2SSYT as well and a 355 Perfect phase but on a 240V machine. I thought at first maybe it was the LEDS but I got replacement lights and same problem. Then I plugged them directly to the wall outlet and no flicker at all so I ruled that out. The fact that both of your machines have this flicker is leading me to believe it has to do with the phase converter or wiring of it. My plan was to use a relay to turn the lights on and off and have the LEDs powered by 120v from the wall instead worst case. I would definitely like to know if you were able to sort this out!
Re: Phase perfect to 480v transformer help needed .
Quote:
Originally Posted by
Gilmax
I'm having the exact same problem on my VF-2SSYT as well and a 355 Perfect phase but on a 240V machine. I thought at first maybe it was the LEDS but I got replacement lights and same problem. Then I plugged them directly to the wall outlet and no flicker at all so I ruled that out. The fact that both of your machines have this flicker is leading me to believe it has to do with the phase converter or wiring of it. My plan was to use a relay to turn the lights on and off and have the LEDs powered by 120v from the wall instead worst case. I would definitely like to know if you were able to sort this out!
What is the supply that is feeding the Phase Perfect, this most likely is where the problem is
What spindle motor does your machine have I thought the VF-2SSYT where 30Hp, you Phase Perfect PT335 is only rated for 20Hp max
If you ran another supply for the leds then you could easily create a Ground Loop
Re: Phase perfect to 480v transformer help needed .
The supply is 240V. Yes the machine says 30hp on it but its "Haas Power" and not really. The phase convert can handle 280amps overload for 4 secs and 64 amps continuous which was well within actual use. I know of other people running 20hp version on the same machines without any issues and I have checked with a clamp meter during actual use and its well within the specs. As for the ground loop, could I just isolate the lights from the mounts on enclosure and just plug them in directly to the wall with a switch or would that still be a potential problem?
Re: Phase perfect to 480v transformer help needed .
Quote:
Originally Posted by
Gilmax
The supply is 240V. Yes the machine says 30hp on it but its "Haas Power" and not really. The phase convert can handle 280amps overload for 4 secs and 64 amps continuous which was well within actual use. I know of other people running 20hp version on the same machines without any issues and I have checked with a clamp meter during actual use and its well within the specs. As for the ground loop, could I just isolate the lights from the mounts on enclosure and just plug them in directly to the wall with a switch or would that still be a potential problem?
That's funny Haas power, Haas does not make the AC spindle drive motors your Phase Perfect is too small for your machine Phase Perfect would not approve of your running this machine on the PT 335
The supply is 240v but how many amps do you have for the supply the voltage is unimportant the amperage is what is important
When you want to run something like this on single phase your supply has to be 1/3 more than the machine spec's
Re: Phase perfect to 480v transformer help needed .
Quote:
Originally Posted by
Gilmax
It's the 355 model and the supply is 150amps dedicated with 125amp breaker on it to phase converter and was all installed by an electrician . The "haas power" is a joke because anybody who has one and compared to another machine can tell you that they rate their spindle power differently than other manufactures. I already disccussed it with phase perfect and they said they had other customers running doing the same thing with no issues. They said they can't "guarantee" that it will be enough but would allow me to exchange if I were having problems. So far I have no problems other than the LED flicker while the machine is estopped and hardly drawing much power in the first place. If the problem only occurred when the machine was actually cutting it would be a different story but it's always flickering slightly no matter what, which leads me to believe it's something else. The OP is having the same problem with his 30hp model as well, so I would really appreciate to focus on that.
The OP is running 2 machines which is way under powered for what he is doing, this does seem though that if this is the machine lights then there is a problem how the lighting is wired Led lighting does not normally cause this problem
Its like I said if your machine runs without any problems then you don't have a problem, you have a light problem which could be just a wiring problem or how the lights power is being supplied, led lighting have there own power supply source something is wrong with this part or it's supply
I have the Led lights in my machine also but don't have this problem I run a PT 380 Phase Perfect
Why is your machine in Estop should never be used unless you have an emergency
