MAIN BREAKER QUAGMIRE - HELP

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Cybatrex

Cybatrex

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Location
Florida
I'm stumped and need some help understanding what and why it's happening. I've tried to research my answer but I'm unable to find the answer I'm looking for. This is what is happening currently on one of my "Emergency Calls".

The Call: The house has no electricity. Customer called the electric company who states the main is on without issue.
IMG_0852 2X.jpg


TEST RESULTS
Breaker "ON" Position:
  • BREAKER TERMINAL 1 TO GROUND - 0 VOLTS (LESS THAN 1V)
  • BREAKER TERMINAL 2 TO GROUND - 0 VOLTS (LESS THAN 1V)
  • SERVICE L1 TO GROUND - 0 VOLTS (LESS THAN 1V)
  • SERVICE L2 TO GROUND - 0 VOLTS (LESS THAN 1V)
  • TERMINAL 1 TO TERMINAL 2 - 0 VOLT
Breaker "OFF" Position:

  • BREAKER TERMINAL 1 TO GROUND - 0 VOLTS (LESS THAN 1V)
  • BREAKER TERMINAL 2 TO GROUND - 0 VOLTS (LESS THAN 1V)
  • SERVICE L1 TO GROUND - 120V
  • SERVICE L2 TO GROUND - 120V
  • BREAKER TERMINAL 1 TO TERMINAL 2 - 0 VOLTS


CONCLUSION: Breaker is obviously not functioning properly. It needs to be replaced. I need to understand why I get 0 Volts from incoming service lines ONLY when the breaker is in the off position. To be clear, I'm testing the service lines before they even get to the breaker, they should always be hot. When you remove the breaker the terminal blades are hot. Very confusing.

Does anyone have any idea what's going on in this situation?​
 
Meter may be bad. When the main is off, what ever IS getting through the meter has a chance to bring that small section of wire up to potential. When the main is on however, all the loads in the home drag down the voltage so you see none. Open the meter pan, and do your tests with the main on and off, before and after the meter. Then get the power company out there.

Sent from my VS987 using Tapatalk
 
Cybatrex said:
TEST RESULTS
Breaker "ON" Position:
  • BREAKER TERMINAL 1 TO GROUND - 0 VOLTS (LESS THAN 1V)
  • BREAKER TERMINAL 2 TO GROUND - 0 VOLTS (LESS THAN 1V)
  • SERVICE L1 TO GROUND - 0 VOLTS (LESS THAN 1V)
  • SERVICE L2 TO GROUND - 0 VOLTS (LESS THAN 1V)
  • TERMINAL 1 TO TERMINAL 2 - 0 VOLT

I need to understand why I get 0 Volts from incoming service lines ONLY when the breaker is in the off position.
Click to expand...

With an open service Neutral (energized or not), SERVICE L1 or L2 TO GROUND should be 0 VOLTS with Breaker "ON".

Any claims to Homeowner insurance or GL policies are void when OSHA is violated by removing main with meter in place.

After meter is removed, service neutral can be checked at meter stabs, and customer-side busing can be meggered.
 
Cybatrex said:
The Call: The house has no electricity. Customer called the electric company who states the main is on without issue.
View attachment 18164


TEST RESULTS
Breaker "ON" Position:
  • BREAKER TERMINAL 1 TO GROUND - 0 VOLTS (LESS THAN 1V)
  • BREAKER TERMINAL 2 TO GROUND - 0 VOLTS (LESS THAN 1V)
  • SERVICE L1 TO GROUND - 0 VOLTS (LESS THAN 1V)
  • SERVICE L2 TO GROUND - 0 VOLTS (LESS THAN 1V)
  • TERMINAL 1 TO TERMINAL 2 - 0 VOLT
Breaker "OFF" Position:

  • BREAKER TERMINAL 1 TO GROUND - 0 VOLTS (LESS THAN 1V)
  • BREAKER TERMINAL 2 TO GROUND - 0 VOLTS (LESS THAN 1V)
  • SERVICE L1 TO GROUND - 120V
  • SERVICE L2 TO GROUND - 120V
  • BREAKER TERMINAL 1 TO TERMINAL 2 - 0 VOLTS


CONCLUSION: Breaker is obviously not functioning properly. It needs to be replaced. I need to understand why I get 0 Volts from incoming service lines ONLY when the breaker is in the off position. To be clear, I'm testing the service lines before they even get to the breaker, they should always be hot. When you remove the breaker the terminal blades are hot.
Click to expand...
There is an inconsistency between your written and table information.

What I pick up on is that the Service Conductors have voltage readings that change, depending upon the Service Disconnect Breaker position.

I submit that you need to follow the [voltage / absence of voltage] upstream from the LOAD side of the 125 Amp breaker to both the LOAD and LINE sides of the meter socket with the meter plugged in. In order to accurately do this, you have to be confident of the Grounding Electrode System that you are using to reference from. Is it connected to a viable grounding electrode and is the grounding electrode conductor continuous to the pictured Service Disconnect? Once you are sure of that, measure from the Service Disconnect neutral bus to the various points along the Service Conductors.

Because of the symptoms you've shared, I don't think you can trust the Power Company grounded service conductor in the Service Disconnect to, in fact, be connected to the transformer, and / or the distribution grid grounds. That is, a splice, or splices, along the circuit path to the transformer may likely be high impedance connections.

If the voltage on the service entrance conductive path is 0 V at the LINE side of the meter, then the connection failure belongs to the power company (I am assuming a simple 120 / 240 V overhead service.)
 
truck41trouble said:
Meter may be bad. When the main is off, what ever IS getting through the meter has a chance to bring that small section of wire up to potential. When the main is on however, all the loads in the home drag down the voltage so you see none. Open the meter pan, and do your tests with the main on and off, before and after the meter. Then get the power company out there.

Sent from my VS987 using Tapatalk
Click to expand...

This. Also, between where you drew the first "L2" arrow and the seconds "L1" arrow, the plastic appears cracked there; possible lug failure behind the plastic?

What happens when you put a load across the terminals? Do you have a 240V light bulb with clips to test with?
I'm with the others who write the meter (or can) is likely bad despite the POCO saying otherwise
 
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Can I guess ?????

the breaker is a load and not a dead short. it is in the same state of "normally something" whether in the on or off position ?????

Hmmm than shouldn't it be glowing ? ;- )

It's somehow connected enough through the breaker that it's only letting partial voltage thru the breaker in a normally something (on) state and breakers in the panel are on so the minimal voltage is getting eaten up by the circuits...?



ok....... standing down :- )
 
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Try another meter (test meter not POCO meter) and see what the readings are. Do you ever get 240V between L1 & L2?

Either pull the meter if you're allowed to and check there first
or
Call POCO and have them pull it then YOU check inside the socket.
 
It almost sounds like the breaker is backfeeding the service. Or maybe there is some funky business going on with the neutral and grounding connections.

Some additional measurements may help clear the confusion - L1 to L2 should always be hot breaker on or off - 240 volts.
 
truck41trouble said:
Meter may be bad. When the main is off, what ever IS getting through the meter has a chance to bring that small section of wire up to potential. When the main is on however, all the loads in the home drag down the voltage so you see none. Open the meter pan, and do your tests with the main on and off, before and after the meter. Then get the power company out there.

Sent from my VS987 using Tapatalk
Click to expand...

I had to give them a buzz because it's beyond me at this point. Thanks for your help!
 
al hildenbrand said:
There is an inconsistency between your written and table information.

What I pick up on is that the Service Conductors have voltage readings that change, depending upon the Service Disconnect Breaker position.

I submit that you need to follow the [voltage / absence of voltage] upstream from the LOAD side of the 125 Amp breaker to both the LOAD and LINE sides of the meter socket with the meter plugged in. In order to accurately do this, you have to be confident of the Grounding Electrode System that you are using to reference from. Is it connected to a viable grounding electrode and is the grounding electrode conductor continuous to the pictured Service Disconnect? Once you are sure of that, measure from the Service Disconnect neutral bus to the various points along the Service Conductors.

Because of the symptoms you've shared, I don't think you can trust the Power Company grounded service conductor in the Service Disconnect to, in fact, be connected to the transformer, and / or the distribution grid grounds. That is, a splice, or splices, along the circuit path to the transformer may likely be high impedance connections.

If the voltage on the service entrance conductive path is 0 V at the LINE side of the meter, then the connection failure belongs to the power company (I am assuming a simple 120 / 240 V overhead service.)
Click to expand...

I delved into more information. The fact that when L1-L2 I got 0 on both reads, it may be an issue with the transformer. They only use 1 phase that splits into 2, rub some magic on it, and bam...240V. No, really though, It may be that one of the lugs is touching the other somehow behind that assembly that's holding the breaker that I can't see.

This guy really explained it best
http://www.anoldman.com/power_systems/understanding_residential_ac_phases

"Most people assume that single phase means that both 120v the legs in the residential application are of the same phase. This is a complete misconception. If the two 120v legs were in phase, the difference between the two would never change, giving you no power between legs:"Graphic3.jpg
Note that as the purple line moves from left to right (time) on the graph, it's "length" never varies so we have no potential or power. At the current position of the purple line, both waveforms are at zero volts. The POTENTIAL between the two waveforms is zero. If both waveforms are at 120v, there is also no POTENTIAL between them.
Potential is the DIFFERENCE between the two waveforms, which is subtractive. The purple line must vary in length for there to be power. Imagine the graph in three dimensions like the triangle on the end of this graphic:
Graphic7.jpg
Click to expand...
 
JFletcher said:
This. Also, between where you drew the first "L2" arrow and the seconds "L1" arrow, the plastic appears cracked there; possible lug failure behind the plastic?

What happens when you put a load across the terminals? Do you have a 240V light bulb with clips to test with?
I'm with the others who write the meter (or can) is likely bad despite the POCO saying otherwise
Click to expand...

I did not put any load across the two lugs but I also drew that conclusion because the lugs were broken on that assembly that perhaps they were touching together in some way. How would this eliminate 240 across the terminals but still allow for 120v L-G?
52381165723__A4E8F941-9DC9-44E3-8E2E-DCA6BD500AAF.jpg52381168103__6327EE5B-50D1-4FC4-A783-48BF1AF3F0D8.jpg52381172654__D89D6640-C434-489A-90DC-69601007EAA3.jpg52381174747__A174B6CF-D93E-4256-9001-6F3EB943A0BB.jpg52381277550__56733141-5C15-4DBF-AC0E-82E0C3A37B62.jpg52381278280__5929E556-2334-4D30-AA56-A916F850DE69.jpg
 
steve66 said:
It almost sounds like the breaker is backfeeding the service. Or maybe there is some funky business going on with the neutral and grounding connections.

Some additional measurements may help clear the confusion - L1 to L2 should always be hot breaker on or off - 240 volts.
Click to expand...
Agreed. What would cause them to not be? What would happen if I had a cable from L1 to L2. Their both hot, wouldn't I just get 120V? I've never done it.
 
I agree with those that say you need to get the meterbase opened and check power on the line/load sides of the meter.

Either a defective meter/meter socket or incoming power problem would be my guesses.
 
Cybatrex said:
I had to give them a buzz because it's beyond me at this point. Thanks for your help!
Click to expand...

The pictures you posted in another post really clarify your question well. First off it verifies that you have a good meter and I can see what you are seeing. That said, anything beyond the first part of what you did requires the utility to either be back out there, or your permission to pull their meter. However, since we are in a new environment, I would strongly suggest that the next time you run in to an issue like this, and if you have to do anything in the meter enclosure while it is hot, you where some PPE. You already know there is something wrong and that something could actually case an arc flash at any moment. Wit the low energy , at least gloves, a face shield and flame resistant clothing.
 
Been mentioned and I am with those - you never mentioned whether you have 240 volts between L1 and L2. If you don't the problem is definitely "upstream" from where you are trying to measure.

Tree branch rubbed through conductors of an overhead service drop sounds like it could be a possibility.

Lost neutral gives you varying voltages to neutral.
Lost ungrounded conductor will still leave you with consistent 120 volts to neutral on the good ungrounded conductor, but varying volts on the one with that has been lost - but any 240 volt loads will never see 240 volts either.

Loss of an ungrounded plus the grounded conductor leaves everything at one potential - unless you place a probe in remote earth then everything will read ~120 to that probe. Sounds like you could be headed toward this last issue as being the problem with what you have mentioned so far.

Go back and make sure you do measure L1 to L2, and also maybe measure to remote known grounded object. If all you have intact is one ungrounded conductor when your main is closed and line to neutral loads are connected - the only "return path" is going to be the grounding electrode, but it may be high enough resistance that very little volts drop across your intended loads, and the only way to measure any significant voltage is to measure to true ground that is remote from your GES.
 
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