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Engineers! Help! (Line Side Harmonic Distortion)


DetroitStillJockey

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Hey guys, hoping someone can help me out here. We have been experiencing lots of "Gremlins" or 'Electrical demons" unexplained equipment malfunctions, ect. I think I have determined that we are suffering from Line Side Harmonic Distortion within our electrical system. Has anyone ever experienced this? What steps did you take to correct it? 

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We have 2 large 3-phase agitator motors and one inverter/VFD controlling the motor on our receiving tank pump. The VFD is only engaged when we are filtering or transferring out of the tank so maybe average one hour per day. Does it produce noise even when not actually on? We also have a mash pump that's 4-wire 3 phase, run that at least an hour or two a day as well. As far as the grounding goes, I'm not even sure where to begin checking it all. I'm thinking the agitator motors are a likely culprit since they run 20 hours a day. We also have a hydrovane compressor that runs often, we are in an ancient neighborhood in Detroit in a 110 year old building... I've got my work cut out for me chasing this down I think. The main symptoms are manifesting in the boiler and in our labeler. The labeler NEVER works correctly. We have changed multiple parts at the manufacturer's instruction to no avail. Just ripped it apart and sent the whole labeling arm/servo back to them for testing/repair. The boiler has fried multiple control boards. We have lost temp control units on all of our bar coolers, we lost a bay door opener to a fried board... the list goes on. What do you think the chances are of it being my equipment producing the interference versus inadequate power quality at the main? Also, on the grounding topic.. has anyone ever researched the effects of a giant copper tank filled with swirling liquid on your power grid? I almost feel like just grounding the still itself might not be a terrible idea. Also to my knowledge there are no line reactors in place upstream of any of this equipment. 

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1 hour ago, DetroitStillJockey said:

We have 2 large 3-phase agitator motors and one inverter/VFD controlling the motor on our receiving tank pump. The VFD is only engaged when we are filtering or transferring out of the tank so maybe average one hour per day. Does it produce noise even when not actually on? We also have a mash pump that's 4-wire 3 phase, run that at least an hour or two a day as well. As far as the grounding goes, I'm not even sure where to begin checking it all. I'm thinking the agitator motors are a likely culprit since they run 20 hours a day. We also have a hydrovane compressor that runs often, we are in an ancient neighborhood in Detroit in a 110 year old building... I've got my work cut out for me chasing this down I think. The main symptoms are manifesting in the boiler and in our labeler. The labeler NEVER works correctly. We have changed multiple parts at the manufacturer's instruction to no avail. Just ripped it apart and sent the whole labeling arm/servo back to them for testing/repair. The boiler has fried multiple control boards. We have lost temp control units on all of our bar coolers, we lost a bay door opener to a fried board... the list goes on. What do you think the chances are of it being my equipment producing the interference versus inadequate power quality at the main? Also, on the grounding topic.. has anyone ever researched the effects of a giant copper tank filled with swirling liquid on your power grid? I almost feel like just grounding the still itself might not be a terrible idea. Also to my knowledge there are no line reactors in place upstream of any of this equipment. 

I'm with Richard.  Have everything checked for grounding issues.  A grounding issue would certainly cause the problems that you described above.   Low voltage could also cause issues like that. Call a licensed electrician and have them meter everything.  Once they do that they should be able to tell you if it is a grounding issue or something else.  

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Blown boards sound more like transient voltage spikes, not noise.  Noisy lines aren't going to fry boards.  It would be easy to tell looking at the boards, if you had a good electrician.  The fact that a number of these have been damaged makes me believe this is a spike issue, not a noise issue - bar cooler boards don't give a crap about noise.

Talk to your electrician about potentially considering a panel-mount surge protector/noise filter, this is a unit that would wire into your main panel.  Typically you see them more often in places that have very sensitive electrical equipment, hospitals, labs, data centers.

They aren't cheap, but they are cheaper than replacing equipment.

This doesn't mean you can skip thoroughly reviewing the electrical installation.  VFDs can throw off very high voltage spikes, 4x the line voltage, however it's typically only the motor that's subjected to it.

 

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Make sure there isn’t a cross between your load (black) and line (white) with an outlet.  We found this to be a problem at one of our propane customers while instilling a new high tech condensing boiler.  Wouldn’t stay running without a reset and fried a circuit board within a week.  The line and load wires were reversed on a outlet in another room on he same circuit in a series.  Reversed and bam. Runs great and no additional service calls. 

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On 1/2/2019 at 5:14 PM, DetroitStillJockey said:

We have 2 large 3-phase agitator motors and one inverter/VFD controlling the motor on our receiving tank pump. The VFD is only engaged when we are filtering or transferring out of the tank so maybe average one hour per day. Does it produce noise even when not actually on? We also have a mash pump that's 4-wire 3 phase, run that at least an hour or two a day as well. As far as the grounding goes, I'm not even sure where to begin checking it all. I'm thinking the agitator motors are a likely culprit since they run 20 hours a day. We also have a hydrovane compressor that runs often, we are in an ancient neighborhood in Detroit in a 110 year old building... I've got my work cut out for me chasing this down I think. The main symptoms are manifesting in the boiler and in our labeler. The labeler NEVER works correctly. We have changed multiple parts at the manufacturer's instruction to no avail. Just ripped it apart and sent the whole labeling arm/servo back to them for testing/repair. The boiler has fried multiple control boards. We have lost temp control units on all of our bar coolers, we lost a bay door opener to a fried board... the list goes on. What do you think the chances are of it being my equipment producing the interference versus inadequate power quality at the main? Also, on the grounding topic.. has anyone ever researched the effects of a giant copper tank filled with swirling liquid on your power grid? I almost feel like just grounding the still itself might not be a terrible idea. Also to my knowledge there are no line reactors in place upstream of any of this equipment. 

Sounds like the issues could be in the control power (not the 3-phase), look for how is the 120 VAC single phase transformed down from 480 VAC 3-phase.  Maybe there is a problem with a transformer or other item.  Are there any short bumps/drops in the power? Very short, just a flicker. If yes, these can be a circuit interrupter tripping on a temporary ground fault and auto resetting, this can be caused by failing power distribution lines and/or trees getting touching the power wires crating path to ground which is detected by the power companies equipment.   Repeated ground fault trips can cause some of the problems described.  If you suspect this, call your power company and ask for engineering help.

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