So your 220v supply 2 x 110 Hot lines and Ground is coming from the milling machine, this is what I can read in your photo
Is your voltage 110v or is it 120v, the standard for NA is 120v/240v for single phase, it can be lower in some area's ??
So where is the neutral coming from for the 120v circuit , it is not very clear how you have it wired
The 240v not ideal, but looks ok except for the 240v Grounding, which also is not clear as to how that has been done/wired
Mactec54
I'll bet when the smoke clears you will find that the neutral wire was open for the control connection and the 110 wire used is the other phase.
See attached video for interesting information.
https://www.youtube.com/watch?v=HsSlQnGCvdg
https://www.youtube.com/watch?v=O-Q0M32puGY
Jeff...
Patience and perseverance have a magical effect before which difficulties disappear and obstacles vanish.
Good information of what can happen, with an open neutral
In his case if it was 240v that would not affect the Drive as it can take 240v, but having an open Neutral would be bad in this case, which is why I was asking the questions about the Neutral
What would happen with an open Neutral in this case, the Ground wire then would become the return path, and a big zap would happen, that would kill the Drive, which may be what caused this to happen, there is something with the input wiring that we can not see in the Photo that is not correct, and I suspect it is to do with how the Neutral wire is being used/wired
Mactec54
Ground (the aluminum case of the drive, or the PE screw in the datasheet) doesn't magically become the return path when the neutral opens.
it should not be possible to apply anything less than 300 vac to the drive and get the internal capacitors to blow up due to overvoltage. (note the datasheet says 300vac peak)
I would expect nothing to happen up to 330 vac between the line terminals and the "ground" as this is probably the nominal voltage of the internal MOVs
Exceeding this voltage will blow the mov, which could take out other components causing a failure, but if they are intelligent then the movs should be in their own little safe space. once the mov blows, then you can increase the voltage between line and "Ground" up until lightning strikes somewhere internally.. but this voltage will not charge up or over volt the dc bus. who knows what it can take, but the point is.. you don't have more than 240 vac anywhere in your circuit, nothing should blow up.
also notice the typo in the image in post #3 it says "Three phase input max 140VAC."
Unless you have created a dead short, which is most likely what has happened
Who said the capacitors are blown, who knows what has blown without having a look inside the Drive
Most component's in these Drives are rated for 600v, so it had a good zap if he was able to see a blue flash
Mactec54
I Don't see a line reactor in front of your vfd, you really should have one on your system especially if you are feeding a logic control side on your servo drives. The VFD can back feed your wires and do alot of damage. Technically in a properly setup configuration, you would have fuses, contactor, single phase line reactor, Emi filter, vfd, rf filter, output line reactor, motor. The input side single phase line reactor keeps harmful harmonic distortions of the line going back into the supply side. If you don't have one you may be back feeding those harmful harmonic distortions into the servo drives.
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sorry havent replied - been away from internet for a few days
im working on a detailed wire diagram and a scenario of the failures and conditions
im also sending the drives and a couple of my motors back to DMM
my friends think one of the motors may be at fault - as the same motor was hooked up to the drives that blew
but ill let DMM determine that
also - could the problem lie with the fact that im running the logic side on 120Volts with a neutral
and the power side with 240 volts = 2 hots?
i appreciate all the replies and input you guys are giving
this is going to be an expensive learning experience for me \
also - the logic sides still work i can access the drives thru DMMDRV.exe
If the 120v is wired/ split from the same main supply then there would be no problem with that
It would be easy for you to check the motor, just use your meter and check each wire to the body of the motor, and then check each wire pair, this will tell you if there is something wrong with the motor, checking these wires will tell you if you have a short in one of the Phases to Ground /Body of servo Motor or between Phases, this could sure damage the Drive if the motor has a problem
I think your motor cables are premade so they should be correct, check them to see if the A B C match Correct, Motor and Drive must match
I did not see this before, it's a bad Idea having 2 different power supply sources
Mactec54
Just throwing this out there, are you using two separate legs from you breaker box?
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He said in the first Post how he has wired it, it would not matter if he did have to of the same leg, just nothing would happen if he had done that
He had power from ( 2 ) different sources, the 120v was correct but the 240v was missing the Ground, if the Ground had been there for the 240v side it would of blown the Fuses or Breaker instead of the Drives
Mactec54
hi thanks for your replysir
could you possibly post pictures of these components together? - maybe links to examples of this sort of setup
i admit my own ignorance in not having protective equipment like this, and i'd like to fix it
also - would these same items be used in front of the DMM servo drives also?
i looked into line conditioners but maybe there is more im missing
Easiest way is to go to automation direct and died a similarly sized VFD they offer to yours, it will give you specific part numbers to use with your VFD size that way. Technically, any VFD should be running a line reactor as the power company's don't want the harmonic distortions back feeding the grid, any place that gets inspected would require them.
So whatever size VFD you have in hp, compare it to the durapulse gs3 VFD line by automation direct. Those are correct for cnc use and there wiring and component diagrams will be helpful. I have a few parts here for another cnc build I'm doing and will snap some pictures!
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i also wanted to add:
my electrician friend and i were discussing this and the possibility that a bad motor may be the cause of all this came up ---
the same motor was on all 3 drives that blew --- he says although it tests out phase to phase with ohm meter
maybe it shorts when it warms up and starts holding position
so i am sending the motor along with the drives back also
Mactec54
A lone filter is not necessarily for the VFD bit for the other components connected to the same power supply. There is an input line reactor which for his installation is what I am referring to, I also run a EMI filter after the line reactor directly in front of the VFD. I also run a 3ph line reactor for the benefit of the spindle motor.
If you think a line reactor does nothing I would suggest you do some additional research. And again it is more for the sake of back feeding g harmony of distortions back Into the supply line side then upstream to the VFD. He is feeding sensitive electronics, computer etc on the same lines going to the VFD. Without a line reactor those components are subject to any back feeding the the 3 phase motor and VFD produce. Not to mention if this is in a residential environment, anything connected to the supply side is vulnerable without the line reactor.. TV's, electronics, etc..
Many folks don't use them as they don't know to use one and many have noise issues when it comes to using a 3ph motor. I have zero noise issues nor have I ever had any. I attribute that to proper wiring, grounding, and use of the correct components. Sure it adds cost initially, but $50-70 bucks is cheap compared to spending a bunch of wasted time trying to track down electrical issues such as the OP is currently dealing with.
Hopefully he gets it sorted out.
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If his VFD is wired correctly and a shielded cable is used between the VFD and the Motor, and the Shields are correctly terminated he won't have a noise problem
You are completely confused as to how a VFD should be installed, here is one example of how a filter is used for a VFD to be EMC Compliant, a line Reactor goes between the VFD and the Motor and in his case it is not needed
Mactec54
I'm not confused at all.. I think you should do some additional research. a second line reactor can go between the VFD and motor and will reduce motor heating and smooth out the wave form, but the primary line reactor needs to go between the supply power source and the Emi filter (pre VFD). The Emi filter isn't going to do anything for harmonics in the lines being back fed due to the VFD and motor. Harmonics are low frequency under 3khz attenuations and are damaging. Rf is your higher frequency 3khz and higher and is more interference problematic. Low frequency harmonics can blow transformers and other supply buffers in components and equipment connected on the same supply line. This includes power company transformers which can be your responsibility to pay for to fix it you are improperly connecting your equipment to their grid. Hence power companies require supply side line reactors in order to be compliant.
The benefit is this also protects your components connected to the same supply lines as your VFD.
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