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Brand new vf2ss with Phase perfect pt 355 low voltage issues

split141

Plastic
Joined
Aug 17, 2019
Evening everyone.

Just got a VF2 ss unlocked today in the garage. Power going to it is provided by 50 amp single phase > safety disconnect > PT355 > VF2ss.

My issue is when we go to ramp the spindle up we get a low AC input alarm and the machine immediately dies. If we rapid the machine around with the spindle turning (low rpm, or high rpm we slowly ramped to), coolant on, and auger on we can get the pendant to say low ac, rapids reduced to 75%.

Single phase into the converter is :232 volts

Outputs from the converter with the machine at idle, no load are :t1, t2: 232v. t1, t3: 236v. t2, t3: 232v (t3 is the generated leg)

When we test the voltage outputs from the converter (at the time of spindle ramp up) we get t1, t2: 226v. t1, t3: 204v. t2, t3: 181v.

We are running the machine on the 243 - 227 V transformer taps in the machine. The next set of taps down are 226 - 211 V.

I called Phase technologies and they suggested we add something after the phase converter that will add inductance to all the legs so they don't see as quick of a voltage drop on spindle ramp ups. It's going to run me an additional $750. My concern is that won't really fix my problem. The only reason I'm running such an expensive converter is people here and on other forums highly recommended them for my exact application. I find it strange that I don't see this issue pop up with everyone else running this converter.

I was thinking that maybe I could try running machine on the lower transformer taps. My concern is getting overvolting issues. I figure over volting is worse than under volting. My current input power would work for those taps because it's within Haas's recommended within 10% input power. It all changes when the spindle ramps up though. How bad for the machine is it to just give a try?

Has anyone else run into this issue? I really don't see much talk about this issue so I was hoping someone could help me out. Hopefully it helps the next person as well who runs into this issue.
 
you need to run your taps down to around 210 on the transformer. you have 1 high leg but your other 2 legs are way too low. try moving your taps down.
 
the biggest thing to also check is the DC bus. the machines wont run below 320 vdc . with the current surge I'm sure its dropping below that and that's what's giving you the alarm. the DC bus can be as high as 450 vdc. I run phase converters in my shop the last 20 years. I also have a VF2 SS . only issues I had with it and voltage are a piston air compressor that would draw to much to much current and I had the same alarm. ended up buying a screw compressor. other issues I had was braking taps. had to move my taps up up 1 , and fixed the issue.
 
You think if I move all three legs down to the next level of taps it will work? It's not going to over volt or anything? That's what my next thing was going to be to try but I obviously don't want to damage the drive.
 
Is the DC buss where the stepped up 240v from the transformer goes to? Did moving taps cause any issues down the line? I'm thinking of trying the next set down.
 
No the DC bus is the voltage is coming out of the vector drive. I'm not familiar with the new control enough to tell you exactly where it is. but in the old control it was in the diagnostics page would show you the DC bus. I'd move them down. when I did Haas installs we ran into this with some phase converters.
 
A few comments and thoughts from a fellow garage newb.... In summer, My taps usually get set lower than in winter. Local AC's units and homes under more AC draw? I get Low Volts alarm if not low enough on the taps. I put lower and don't have the issue. Anyway- A few things I need to do to ensure I get good supply in the Garage to a VF/4: I turn the house AC off in the house when running a job. Rather than use the big 100gal 240 compressor from the same current source, I run a smaller 30gal 110 from a different house circuit than the garage. Just a few items I do for good power source control to a garage band VF. :-)
 
all good points country guy. the only thing I may differ on is the Super speed machines use the same amount of air as 4 standard Haas combined . most smaller compressors cant keep up. I went with a single phase screw and haven't looked back since. it runs unloaded til it needs air ( I have 4 CNC machines I run at the same time) and it keeps up with the load. before the vf2 ss showed up I could run the other 3 on a 5 hp 60 gallon tank and it hardly ran. added the vf2ss and I was having lots of low air alarms even if it were the only machine running .
 
Morning everyone! Thanks for all the replies! Here is an update:

So changed the taps down and got 100% ac line, and 336 volts dc on the diagnostics page. Still had my ramp up and shut off issues when the machine would try to ramp to 5k and up. Called Haas is Cali and they suggested trying the even lower tap. That also didn't help and I also think that might cause an over volt in the future.

So I've been thinking why do tons of people run this converter with absolutely no issues? Why do I seem to be the only one with these issues? I'm not an electrician so in my mind I'm thinking if the machine is getting full power without tripping the breaker it can't possibly be a conductor issue.

Turns out it was a simple issue of wire gauge size. I'm running 8awg in romex from the box to the knife switch. At the knife switch the gauge changes up to 6awg. Than into the converter and out into the Haas. I ended up changing the 8 gauge into 4 gauge into the knife switch and that started to relieve my issues. I still had the low voltage warning when it would ramp and the lights would flicker but instead of the machine quitting on my she pulled through and continued to ramp all the way up to 12k.

Tonight I'm going to change the 6 gauge from the converter into 4 gauge and that should relieve my issues further. In reality 2 gauge might be a smarter choice but 4 gauge should cover my aluminum cutting demands till I get into a bigger building.

Again thanks for everyone chiming in, as silly as this fix was. I hope this helps someone like me in the future!
 
you know I was thinking about that as I ran 0 wire to my machine. but was thinking you may have had a electrician do the calculations and wiring for you. glad you figured it out!
 
I was in the same exact spot with my Speedio and Phase Perfect. Set it up in my garage and had voltage alarms, but I was seeing overvoltage. House wiring is at a handicap next to industrial wiring. You’re at the mercy of how much local power usage there is and how much power is available. My lights flicker every time the machine spindle starts or stops. I fixed my issue by bucking the voltage lower, which also really helped minimize the voltage spike/dip. I was seeing a baseline of 247v with drops to 218v during spindle start. Now the machine sees 194v and dips only go down to 180-ish. Might be a solution to consider. Different machine with the opposite problem, but being lower in the voltage range seems to make for a narrower voltage change from the spindle.
 
Yea I've been thinking about using a buck booster to boost to 240v. I'm still having low voltage issues but it's better than it was with the bigger gauge. I'm getting 194v out of the converter on both the input single phase and the output 3 phase on a ramp up. After at the circuit box I'm getting 211 which I believe is okay. Is your 218v read out of the converter? I'm worried if I buck boost to 240 the transformer wont be fast enough. Would you boost the single phase or the output three phase?
 
I'd do all 3 phases. when I was tech it wasn't unusual to have 1 high leg. the only thing that Haas said was always use it as your middle feed. if you had to swap phases, do it with the outer 2 legs.
 
I learned this lesson the hard way on a different project for a datacenter. The input wire sizes matter greatly on current inrush or high demand applications on the single phase side. I used #2 wire for all of my supply to the 3 phase breaker box and then #8 thhn out to the machine.
 
Yea I've been thinking about using a buck booster to boost to 240v. I'm still having low voltage issues but it's better than it was with the bigger gauge. I'm getting 194v out of the converter on both the input single phase and the output 3 phase on a ramp up. After at the circuit box I'm getting 211 which I believe is okay. Is your 218v read out of the converter? I'm worried if I buck boost to 240 the transformer wont be fast enough. Would you boost the single phase or the output three phase?

Just registered, first post here. I've been reading this forum for so long I thought I had a login:)

I'm having the same problem with my 2019 VF2SSYT. It shuts down on low voltage when ramping the spindle up. Moving the wires to the 227-243V taps helped and put the line voltage gauge at 100%. It still shuts down ramping from 0-6000RPM., 0-5000 is ok, but the low voltage icon flashes and goes away. I moved the wires to the next lower tap which helped a little bit. Still shuts down on the low voltage alarm 160.

I'm using a 40hp rotary converter and this machine is the only thing on it.

Has anyone found a solution?
 
Just registered, first post here. I've been reading this forum for so long I thought I had a login:)

I'm having the same problem with my 2019 VF2SSYT. It shuts down on low voltage when ramping the spindle up. Moving the wires to the 227-243V taps helped and put the line voltage gauge at 100%. It still shuts down ramping from 0-6000RPM., 0-5000 is ok, but the low voltage icon flashes and goes away. I moved the wires to the next lower tap which helped a little bit. Still shuts down on the low voltage alarm 160.

I'm using a 40hp rotary converter and this machine is the only thing on it.

Has anyone found a solution?

What D.D. mentions is critical. Also make sure you have heavy enough wire gage. Look for change on each leg at the point when it faults. Something to also check is if your incoming wires are seated deep enough in the machines terminal blocks.

But when you've been there done all that and still having the problem then do what fixed that same problem for me, go back and put a good manly tighten on the heavy wires in your machine from L1, L2 & L3 to contactor to power supply, spindle drive and DELTA/WYE if you have it.

Hope it helps.
 
whats your line power? and whats it coming out of the RPC ? also what tap did you put the wild wire on?

Line power is 242v.

RPC is

L1-L2 242
L2-L3 245
L1-L3 246.

L3 is the generated leg. I put the generated leg to the center tap of the input on the machine.
 
What D.D. mentions is critical. Also make sure you have heavy enough wire gage. Look for change on each leg at the point when it faults. Something to also check is if your incoming wires are seated deep enough in the machines terminal blocks.

But when you've been there done all that and still having the problem then do what fixed that same problem for me, go back and put a good manly tighten on the heavy wires in your machine from L1, L2 & L3 to contactor to power supply, spindle drive and DELTA/WYE if you have it.

Hope it helps.

Wire size is

2ga aluminum from Garage panel to Barn panel
2ga aluminum from Barn panel to RPC
4ga aluminum from RPC to junction box near machine
6ga copper from junction box to machine input

Tonight I added 2ga aluminum wire in parallel to the existing wiring from the RPC to the machine input. This helped a bit. I can go 0-9000 without it shutting down now.

I'll try tightening everything tomorrow and see if that makes any further difference.

I am thinking of raising the voltage output of the converter and moving the wiring taps on the machine to bring the voltage back to 240. Not sure if this will do anything or not.
 








 
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