any great industrial technicians here?

[Bear513]

I have a major problem with a Siemens A.C. Drive I can't figure out why

Back story been in injection molding for 30 years delt with little 40 toners to the big ones 3,000 tons as long as a house two story tall

So now my Proplem I never seen this before, we have a little 160 ton electric that when loading up she throws a hot to ground, her fuses don't blow, the 100 amp switch gear on her don't blow, it goes all.the way back to our substation.

I don't understand this it turned 3 little A.C. Drives on our conveyors on machines 300 feet away in to bombs, fire balls, throwing there guts out 10 feet away , i never seen it before

I am the lead maintenance guy on third , we had the power company in here and nothing wrong on their end

Our light are 480v and I noticed they would dim

So my manager came in and we shut everything down.

Started all 20 machines on that substation one by one the huge 3,000 toners hydraulic machines and finally to this tiny all electric machine.

Any one have any ideas, because I don't get it

Asking here because I know most of you a pretty smart and don't feel like signing up to another forums , I have seen electricity do a lot of crazy things but not like this

[Fastjack]

This is 3 phase ? have you lost a neutral ?

[Bear513]

This is 3 phase ? have you lost a neutral ?

Yea it is a 3 phase star deltra the power company told me it was fine,.thanks for reminding me, I remember 2 years ago when I my moved into a mobile home and my 50 inch t.v. Didn't work or micro wave it was the neutral, it was lose, I bet you that's what it is, going to text my boss

[hoosier]

There is no neutral in 3 phase power, has anyone checked amp draw ?.Sounds like a direct ground somewhere , you need to isolate the the power supply from the load ( motor and starter ) and energize . You might need to check the motor windings with a megohm meter to measure winding insulation strength to ground.

[Fastjack]

I was asking 2 Questions ---guess I should have separated them

[Bear513]

There is no neutral in 3 phase power, has anyone checked amp draw ?.Sounds like a direct ground somewhere , you need to isolate the the power supply from the load ( motor and starter ) and energize . You might need to check the motor windings with a megohm meter to measure winding insulation strength to ground.

Talking ground/neutral

They are the same

Update that substation has a floating leg, to save energy, meaning two legs of the 480 is always hot, the third leg floats from the substation hot.to not

Never seen it before up in Chicago

we put a new motor in it and properly grounded it all the way to the power company

It's been running fine