Need for SURGE SUPPRESSION Discussion

[b_faster]

On 1/23/2024 at 7:59 PM, Tom Cherry said:

As I understood most of the “Open Neutral” examples over the years, many…maybe even a majority were issues at the pedestal or in the errors or code violations at or in the CG distribution.  Most were poorly wired 50A receptacles where the Neutral was not properly connected.  Other examples were where the receptacles were corroded or worn so that the Neutral pin hole was “reamed or worn out”.  

The other ones, and I was the victim was a bad internal crimp of the Neutral wire to the Neutral terminal in the plug.  In addition, with the spring contacts on the reels like mine,,,,where the contacts “ride” over a ring….that will also often result in an open circuit. Folks that fulltime and pull out the cord to max on the MH and leave it there for months often will pit or erode the contacts and the “HOT” ring.  Most, that frequently pull in and out and do NOT always pull to full extension rarely have issues.

YES, there could be a transformer issue….  BUT….go BACK to how most high voltage (13,000 VAC) lines are run.  You have only 3 conductors.  The ground is always an EARTH.  Look at the lines or the wires.

You only get a neutral from a step down transformer.  YES, the power company can have a bad transformer or the incoming service can be improperly run.  That is why, and Rick, our tech code guy, might chime in and correct or embellish or provide more insight….  There is NO NEUTRAL on a high voltage feed.  Pad or pole mounted transformers, near or at the Point of Service are the “origination” point for a Neutral.  Then, code says….BOND THEM SUCKERS at the POS in the FIRST panel.  Believe me….an improper ground to neutral or an undersized “bond” will hurt or scare you to death.  We had a “GE GOLD MEDALLION” house in the mid 70’s.  That was the THING….use all the juice….if was free and readily available.  Our local provider, Duke Energy….not a slouch provider, followed all the GE specs.  Put all the breakers outside….had the incoming and meter in one box….and the breakers in a side by side with an interconnect.  OPPS…the GE panel had a piece of 18 Guage galvanized sheet metal “bonding strap”.  My wife got stray voltage when she was barefooted and had her hand on the PAINTED dryer cabinet and pushed the start.  She screamed….and finally, after tearing apart a new dryer and testing every switch and control, I relented…. Got out the county building inspector and the installation contractor and a Duke Rep.  These were down to earth folks.  They measured the voltage.  There was almost 120 VAC potential from the still curing concrete in the basement to the cabinet.  I had her hold a meter lead….one side to the dryer cabinet and the other in her hand.  She screamed when it hit about 75 VAC, and to this day, will NOT hold a meter lead and help me troubleshoot.

Bottom line….when there is a weak or NO Neutral (open), the AC on line 1 will backfeed and you get upwards of 175 VAC across the “neutral” and Hot on both sides of the line.  Of THAT, I am sure….as I tested and measured and it was exactly that way.

SO….my point….an open neutral IS DANGEROUS.  And it can be on “our side” of the 50A pedestal or in the Pedestal or at the main panel or “upstream”.  Only troubleshooting can isolate it….

MODERATOR EDIT

There was a concurrent or VOLTAGE issues topic that delved into the new THREE PHASE Pedestals at some CG.  That new topic was inadvertantly merged into this one. It has been removed and merged with an ongoing one....THREE PHASE.  Sorry for the confusion.  Way TOO MANY Electrical issues and Surge Suppressors and Pedestals and such.  This one pertains to the original "potential open neutral and all "3 Phase" posts have been removed and houskeeping should be complete.

END OF EDIT

Tom, 

I don't disagree with what could be a problem with RV and power systems and how split phase power is designed.  

However, in replying to this issue, it was obvious the issue is/was the neutral line.  His measurements were on the receptacle in the storage unit, outside of his RV,  I.E. the entire facility appeared to have an issue as the RV next door was damaged due to this problem.  The neutral in this case is not carrying the return current to the center tap of the secondary of the transformer.  What is happening is that other circuits are creating a voltage imbalance.  Typically the earth ground bound you referenced is carrying this load, just poorly.   It is amazing the paths the current will find.  

When I stated the problem will be "from the transformer" that is a short form in my world for it is on the feed side of the panel.   I work in the medium voltage world, but I can fake it in low voltage distribution when I have to.  🙂 

 It is possible to have no earth bond and still have balanced secondary legs. 

[Georgia Mike]

On 1/22/2024 at 8:49 AM, Tom Cherry said:

The ones used in the 2006 units were known to fail

I have an 06 Dynasty and have the Surge Guard 40250. There is a newer model 40250RVC. I can find in the specs of mine that it will shut down if the voltage is under 102 or over 132 but I don’t see any reference of surge protection built in as the RVC model does. I have a built in Huges Autoformer  that does have surge protection so I feel that I am protected from spikes. Does the 2006 era Surge Gaurd have a high failure rate? So far mine has been ok and I pull the cover off once a year and tighten the connections.

[Robert92867]

In 2006/2007 I was in Indian Oaks Trailer Ranch in Temecula CA.  I lived there for 2 years while working at the Lake Skinner WTP Expansion.  The voltage was always a little off, one day it was completely off.  I toughed it out without power for a few days while they brought in a crew to fix the problem.  To my utter amazement, they dug up hundreds of feet of direct buried aluminum conductors (THHN). Some of the conductors were bulged to twice their size with aluminum oxide.

[Steven P]

Update:  the storage unit owner had his electrician and the power company check everything out.  Other than a stuck open main breaker, nothing else has been discovered.  I mentioned that people here seem to feel it may be coming from the power company and possibly a transformer issue.  He said he'd reach back out to the power company to push them further.  All volts I checked on Wed were as expected. Thanks all!

[b_faster]

16 hours ago, Steven P said:

Update:  the storage unit owner had his electrician and the power company check everything out.  Other than a stuck open main breaker, nothing else has been discovered.  I mentioned that people here seem to feel it may be coming from the power company and possibly a transformer issue.  He said he'd reach back out to the power company to push them further.  All volts I checked on Wed were as expected. Thanks all!

Steve, 

                They found a "stuck open" main breaker.  Is it possible the service entrance is 3 phase?  If so, then the issues will be downstream of the power company. If you can see the entrance service, specifically if we can see the main breaker panel, typically we can tell the type of "feed" from the power company, 3 vs 1 phase.  I need to look at 3 to 1 phase options that may cause your initial findings if a main breaker issue occurs, I.E. 1 or 2 phases aren't delivered.   Your initial findings were textbook loss of neutral at the phase split.  

 

 

Edited January 27 by b_faster

[Benjamin]

It's very unlikely that the utility is causing this problem.  It looks like a classic shared neutral circuit that has a weak neutral connection at some point.  In your first pic in the first post, I see a rectangular "decorator" cover on a conventional double outlet, and I see an orange extension cord that appears to go through a hole in the wall, both are huge red flags that the wiring has been klutzed up.  Before I'd hook back up, take a heater and plug it in on high to one of those outlets, then read the voltage on that outlet and the other one, then move the heater to the other one and read voltages again.  The voltage will be fine with no load, but show the weakness under load.  The electrician should know that, but it's your RV you're plugging in. 

[Steven P]

On 1/28/2024 at 5:52 PM, Benjamin said:

It's very unlikely that the utility is causing this problem.  It looks like a classic shared neutral circuit that has a weak neutral connection at some point.  In your first pic in the first post, I see a rectangular "decorator" cover on a conventional double outlet, and I see an orange extension cord that appears to go through a hole in the wall, both are huge red flags that the wiring has been klutzed up.  Before I'd hook back up, take a heater and plug it in on high to one of those outlets, then read the voltage on that outlet and the other one, then move the heater to the other one and read voltages again.  The voltage will be fine with no load, but show the weakness under load.  The electrician should know that, but it's your RV you're plugging in. 

Thanks all for the input.  I'm sharing this w the storage unit owner.  As far as the pic. That orange extension cord doesn't go thru a hole in the wall, it runs up the side of the garage door and over to the garage door opener.  I unplugged it at that time to check the voltage.  I believe there are 10 bays and likely all plugged like this.  I've been using this unit since 2018 and not experienced this til now.  They are coming back out Thurs.  Another update:  Sunday I checked again and my surge protector was on and fine but had shut off at some time bw Wed and Sun for volts below 104 on one leg.