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Milling machine flipping breakers

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Plastic
Joined
Aug 17, 2018
I have been lurking around for the past couple of months and decided on a Supermax mill. My question is....

When I start my mil or stop it I flip lots of breakers. One time I started it then one breaker flipped, then during a pass another breaker flipped, then when I hit stop on the vfd two more breakers flipped. The strange thing is that the breaker I am running the mill on hasn't flipped yet. My dad is a master electrician and just retired after 30 years and he has never heard of this. Does anyone know what to do?

Also I can run the mill for 30 min and it never flips the mills breaker.
 
I have been lurking around for the past couple of months and decided on a Supermax mill. My question is....

When I start my mil or stop it I flip lots of breakers. One time I started it then one breaker flipped, then during a pass another breaker flipped, then when I hit stop on the vfd two more breakers flipped. The strange thing is that the breaker I am running the mill on hasn't flipped yet. My dad is a master electrician and just retired after 30 years and he has never heard of this. Does anyone know what to do?

Also I can run the mill for 30 min and it never flips the mills breaker.

Your Dad must have retired before GFCI became a "thing". Not the ONLY culprit, but the most commonly annoying.

Ask him to look again, emphasis on "correctness" of line hots, Neutral, protective Earth (AKA "Ground") management, outlet and breaker types.

Then (cheap one, is it?) VFD noise getting out and about . into "the wild." Some of the less-affluent ones "moonlight" as long-wave radio transmitters for spare change.

I trust he'll grok it. Or he'll know who to call with a 'scope.

Any fixing needs to be done on your "local wire".

All the longer "wire" to PM can do is help guide yah as to were to look.
 
Just to qualify things here a wee bit (and make you posting
easier to understand)

Machines Trip Breakers

People Flip Breakers
 
Just to qualify things here a wee bit (and make you posting
easier to understand)

Machines Trip Breakers

People Flip Breakers

Well at this rate I need a machine to flip the breakers back.

Yes it is a cheap vfd. I thought about a static phase but I didn't want to lose so much power. I got a suggestion from a buddy to switch the grounds from the ground bar in the box to the neutral bar. It slowed the tripping down.
 
GFCI, yeah could be.

If this is in a residential situation, then also the required AFCI breakers for certain areas might also be an issue. Some are both, double whammy.

The "hash" fed back up the line by the VFD can trip GFCIs, but can also fool the AFCIs into "thinking" there is an arc, which trips them.
 
It is residential. I have GFI outlets. Plus the breakers have some sort thing that lets you push a button to test the breaker.
 
Well at this rate I need a machine to flip the breakers back.

Yes it is a cheap vfd. I thought about a static phase but I didn't want to lose so much power. I got a suggestion from a buddy to switch the grounds from the ground bar in the box to the neutral bar. It slowed the tripping down.

It should not have, actually. Those are meant to be at near-as-dammit identical potential with respect to Earth at the service-entrance panel, anyway. Typical "residential" it may be the ONLY "load center", too.

Your neutral & grounds may not be up to snuff. You may have OTHER loads (120 V) already badly imbalanced.

Resolution, however? "with luck" better wiring practice, load side.

Not so lucky, it may involve either a less rude VFD, ELSE some add-ons to the one you have. Some of those add-ons can cost-back all you saved when buying a cheaper VFD.

Or more.
 
I have a fair amount of experience with VFDs but not much at all in the way of problems. Are we dealing with a Bridgeport type mill where the VFD would be powering the the entire shebang. You say "flipping breakers" where prior to the vfd or after, are you running power feed while cutting? Is this a single to three phase VFD and what brand? During the installation of the VFD did you tune it? By tuning you can do it 2 different ways that I am aware of. What tuning does is measures the resistance of each of the 3 windings in the motor and based on those values once they placed into the VFD it (gets a tad bit above my pay grade here) will run more efficiently. Corrections and comments please.
Other way is to make the resistance measurements your self and referring the chart put the values into VFD manually.
What it boils down to is in the info that came with the VFD there should be a flow chart set up and a bunch of parameters that need to be set. Most VFDs will allow you to auto tune, where the VFD does the measuring and tweaks the appropriate parameters. Others you have to measure then go through the chart and change things manually.
Another way to skin the feline would be to call the manufacturer (good luck, getting hold of Hung Low Charlie) explain the problem try his suggestions. Also if you have a clamp on AMP meter see what each leg is pulling loaded and unloaded.
Good luck,
D:cool:
As far as the GFI issue pull it the fuck out and replace it with a regular breaker. If your not familiar and comfortable with all I said have Dad or a certed elechicken do the work. Be safe, ya can always buy a new whatever but ya can never get new you.
 
-Are we dealing with a Bridgeport type mill where the VFD would be powering the the entire shebang- Yes
-You say "flipping breakers" where prior to the vfd or after, are you running power feed while cutting? No I do not have a power feed.
-Is this a single to three phase VFD and what brand? Yes it's a single to three phase. I think it's brand is on the banned don't talk about it list. It's a lapond bed.
-During the installation of the VFD did you tune it? By tuning you can do it 2 different ways that I am aware of. What tuning does is measures the resistance of each of the 3 windings in the motor and based on those values once they placed into the VFD it (gets a tad bit above my pay grade here) will run more efficiently. I have not done any tuning.


As far as the GFI issue pull it the fuck out and replace it with a regular Breaker. I can do that I ran this wire and wired everything.

Would a rotary converter fix these issues?
 
Because if the rotary converter will prevent the gfi breakers from from tripping then buying a rotary converter is cheaper than buying new breakers. I would need to replace 11 breakers.

So I figured out my breakers are two type. Type AFCI and type CHAF
 
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Because if the rotary converter will prevent the gfi breakers from from tripping then buying a rotary converter is cheaper than buying new breakers. I would need to replace 11 breakers.

So I figured out my breakers are two type. Type AFCI and type CHAF

Eaton / Cutler-Hammer, shall we presume?

I'm a third-generation Square-D guy, "QO" since early days, some of 'em fifty years and still in service, (Group Schneider property since '91), but C-H are "OK", too.

Regardless.. any decent "listed" brand, your breakers are not the cause of the fault. Only the messengers pointing out that you HAVE a fault.

Don't shoot the messengers.

Go dig a hole, recruit any passing cat to show you how to cover the VFD.

Cat's are such serious experienced critters when it comes to covering up shit, it largely goes unremarked. As with dogs licking their nether parts, whom in their right mind would care to interfere, anyway? Person could get stuck with the duty, long-term, "GS5" pay level and all.

Let us know if you catch a cat replacing circuit breakers that ain't even faulty, though.

"Pictures, or it didn't happen!"

:)
 
Because if the rotary converter will prevent the gfi breakers from from tripping then buying a rotary converter is cheaper than buying new breakers. I would need to replace 11 breakers.

So I figured out my breakers are two type. Type AFCI and type CHAF

There are many know nuisance problems with most brands of AFCI breakers tripping, especially prone are some of the members beloved Sq D QO products. They are still making improvements to the products to remedy some of the known issues. Newer ones are better than older ones, and some manufactures are supplying replacement units if you contact them and give the date codes on your units.

There are other forums that discuss this issue in detail. There is also a way to disable the AFCI protection and use your existing breakers, but you will have to read that for yourself. I can't condone the bypassing of a required function in your area, but it is doable if you search.

You can read more about common problems HERE, just search AFCI and go through the results.

SAF Ω
 
What is the ampacity of each breaker and the other loads on each?

I was maxing out the electrical system on an old shop before we had the chance to rewire it, and I would always trip the 70 amp upstream breaker and never the 60 amp breaker the equipment was running one, because the 70 amp breaker also fed the lights which drew 20 amps.
 








 
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