Rick Christopherson
Senior Member
So you are grasping at straws, but you want to mock me for not grasping at those same straws? :lol:
The original symptoms didn't rule out an open neutral, but they also didn't directly point to one either.
Voltage on hose bib...
- Thread starter stickboy1375
- Start date
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The original symptoms didn't rule out an open neutral, but they also didn't directly point to one either.
- Location
- Windsor, CO NEC: 2017
- Occupation
- Service Manager
What's the voltage with the main off?
Sierrasparky
Senior Member
- Location
- USA
- Occupation
- Electrician ,contractor
Sticky does the problem still remain?
- Location
- Illinois
- Occupation
- retired electrician
I can't really see that with a utility service. There will be a grounding electrode at the transformer and the primary and secondary grounded conductors will be connected together.
- Location
- Massachusetts
I see no straws.
IMO the symptoms do in fact point directly to a neutral issue.
- Location
- Massachusetts
If it is not a complete metal water line the current would likely be low enough to look like the typical zero reading on a field meter.
cadpoint
Senior Member
- Location
- Durham, NC
Turn off the meter and see what your reading are, as said. Then see what that is to your ground.
A wire is on the a pipe in the house, is my guess!
kwired
Electron manager
- Location
- NE Nebraska
- Occupation
- EC
I think he means there is no main bonding jumper and the water pipe is bonded to the EGC. I can see that being a problem. Easy check would be to see if there is neutral to ground voltage at receptacles - assuming the EGC is not terminated on same bar as neutrals at service equipment.
Be careful, if there is an ungrounded conductor energizing the EGC you will have an arc flash when installing bonding jumper - so you still need to verify the source of the voltage. If a low impedance meter diminishes the voltage when testing it is probably voltage from capacitve coupling.
Add: Just remembered someone was being shocked by hose bibb. Probably not very likely to be voltage from capacitive coupling, but still not entirely impossible depending on conditions.
Rick Christopherson
Senior Member
The OP said that turning on a lot of loads in the house increased the voltage at the hose bib, but did not effect the voltage of the neutral in the panel. If it was a floating neutral or a high impedance neutral, he would have seen a voltage imbalance in the panel. Instead, according to the OP, these voltages appeared to be locked down pretty tightly.
If neutral current was flowing on the ground wire (broken neutral) a small load like a microwave would not result in a sufficient voltage drop to raise the hose bib voltage as high as it did.
The most telltale sign is that when increasing the balanced portion of the load (not increasing neutral current) also increases the voltage of the hose bib.
All of these signs tend to suggest a floating ground system (possibly not just the hose bib). That's not an absolute answer, but the symptoms are strong. If it was just the microwave causing this voltage, then I would think it was just the hose bib that was isolated. But because many loads in the house cause this, it tends to suggest that there are many circuits where an induced voltage from ungrounded conductors is being imparted on the floating ground system.
The biggest problem with this suggested answer is the unlikeliness of it happening. That's because the internal grounding system has to be broken from both the earthen ground, and from the ground-neutral bond. The simplest solution to this would be if the main bond is located somewhere outside of the main load center. So the question to the OP would be, where is the GEC and G-N bond?
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stickboy1375
Senior Member
- Location
- Litchfield, CT
let me fill in the blanks, no matter what, if I shut the main off, the voltage disappears, this is a residence with a well, no city water, the more load in the house the higher the voltage my meter reads off the hose bid to earth, from the transformer to the pedestal meter is a 3 wire, from the meter to the house is a three wire, at the house panel, we have a main breaker, neutral bonded to ground, water bonded, two ground rods outside of residence. Pretty simple setup, i have no current readings on the GEC or water pipes. The voltage always stays the same under load, never changes, so why am I getting such high voltage on the hose bib as the load increases?
stickboy1375
Senior Member
- Location
- Litchfield, CT
zero
stickboy1375
Senior Member
- Location
- Litchfield, CT
yep, it does...
- Location
- Windsor, CO NEC: 2017
- Occupation
- Service Manager
Could there be a subpanel that all the loads you're turning on are fed from? Your symptoms aren't adding up. :blink:
ETA: I would continue by checking all branch circuits for a downstream neutral-to-EGC connection, but it's a stab in the dark.
ETA: I would continue by checking all branch circuits for a downstream neutral-to-EGC connection, but it's a stab in the dark.
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stickboy1375
Senior Member
- Location
- Litchfield, CT
no sub-panel George, this is how it is, from xformer pad to meter, from meter to house... neutrals and grounds bonded at house, water bonded at house, ground rods at house. Not really sure what else to say, but power company basically left the problem in our hands.
Rick Christopherson
Senior Member
You said that all of the voltages in the main panel are always correct. I assume that means you get the normal voltage phase-to-neutral and nothing neutral to ground.
This is a long shot idea, but next time, turn on only 240 volt loads and see if the voltage at the hose bib still increases. It sounds like something is making the entire system rise in voltage relative to the local earthen ground. I am not an expert on utility systems, but I'm wondering if their transformer was not bonded if it is just too much for your grounding system to handle.
This is a long shot idea, but next time, turn on only 240 volt loads and see if the voltage at the hose bib still increases. It sounds like something is making the entire system rise in voltage relative to the local earthen ground. I am not an expert on utility systems, but I'm wondering if their transformer was not bonded if it is just too much for your grounding system to handle.
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stickboy1375
Senior Member
- Location
- Litchfield, CT
The more load I add the higher the voltage increases, this eliminates the one circuit issue.
stickboy1375
Senior Member
- Location
- Litchfield, CT
one thing I did notice, as i turned on more 240v loads, the voltage did increase on the hose bib, so when i turned on the dryer, range, ac, the voltage on the hose bib skyrocketed...
Rick Christopherson
Senior Member
In the late edit I made to my post, I suggested the possibility that the utility transformer is not bonded properly. Without a reference, the secondary can float in voltage. The more load you put on it, the higher its voltage may drift toward the primary's voltage. I am just speculating, and I am not even sure how to confirm it. Because your grounding system is limited to just the 2 rods and an assumed well casing, it would be easy for this situation to locally elevate the grounding system voltage.
When you have an elevated voltage at the hose bib, check the voltages from each phase to an earthen ground (not the GEC). Actually, check voltage at the GEC too. If I am right, you might see one phase-ground voltage increase above 120 volts, and the other being reduced by the same amount. Just a guess at this point.
kwired
Electron manager
- Location
- NE Nebraska
- Occupation
- EC
Could still be POCO primary neutral problem. If this is a farmhouse or other somewhat isolated location and there is no other services in close proximity, by reducing secondary load you are also reducing primary load therefore if it is voltage from bad primary neutral it will also decrease.
The more you load the secondary the more the primary will draw and the more the voltage drop through a bad primary neutral connection will be. In a location where there are other other transformers in closer proximity the voltage drop on primary neutral from those nearby transformers will still be there even when yours is not loaded.
A drop of 25 volts in a 7200 volt primary will not even be noticed on a 240 volt secondary, it is less than 1/2%, yet it can raise voltage from anything bonded to it to earth.
Convincing POCO that this may be the problem can be hard to do with some POCO.
The more you load the secondary the more the primary will draw and the more the voltage drop through a bad primary neutral connection will be. In a location where there are other other transformers in closer proximity the voltage drop on primary neutral from those nearby transformers will still be there even when yours is not loaded.
A drop of 25 volts in a 7200 volt primary will not even be noticed on a 240 volt secondary, it is less than 1/2%, yet it can raise voltage from anything bonded to it to earth.
Convincing POCO that this may be the problem can be hard to do with some POCO.
- Location
- Massachusetts
The change in load on the primary side of the trans would be almost nil.
I think 60 amps of added load at the house would be about 1 amp on the primary given a 13.8KV primary.
So while possible it seems unlikely in my opinion.
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