I have a similar problem with surges and outages. I've had the local power company check their service and intall a monitor. However, they don't monitor the neutral leg. They told me the problem was on my side of the panel and I had a spike draw of 30 amps and unbalanced voltage during these times. They saw a problem on both hot legs, leading me to believe that it was isolated to my 220 equipment, which is limited. I started by turning off all the 220 circuits, but I still experienced the problem. I then had an electrician come in and tighten all the neutrals in the panel and the power company check their neutral connections again. Things seemed okay for a day or so, but it is back. What do I do next? Isolate every circuit? The surge/outage appears to occur throughout the system, which leads me to believe it is in the panel. Okay, my theory is that in very dry soils, like now, the ground is no longer truly grounded. Is this my next check?

I don't have a big picture. Am I arm when I sense industrial setting?

Would "transformer breakdown" ring any bells?

Can you define and quantify :


The surge/outage appears to occur throughout the system,

A surge can be considered as a voltage rise above normal, and an outage is obvious.

You should have an electrician come in with a power analyzer to monitor the power for a few days. A good recorder will monitor the neutral by checking both the 240 volt and 120 volts.

If recorded at the panel, or as close to the meter as possible, will help narrow down the problem to determine if the utility is the cause.

Still sounds like a loose neutral, either in the meter, connections at the point of service on your building, or at the utility transformer.

A recorder will help determine if connections in the 240 volts lines are the cause also.

Have you seen outages on 240 volt devices?

Did they pull meter and check connections there?

First of all, I appreciate all the support and the quick response. I need to explain that I am a Civil Engineer and have good logical thinking and limited common sense. LOL So, now you know that I am just as much as a problem in my analysis. LOL. I have monitored both incoming hot legs over a 24 hour period, individually, with my Fluke 87 V. Things look okay there (ie voltage was within reasonable range during glitches).

The spike that the power company saw is possible as I live in a rural area and operate my own well and pump system. My pump should only draw a maximum of 20 amps (ie 3 times the running amps of 6.8), so it appears to be in a normal range. The power company has visited twice in my presence and reclamped all the neutral connections on their side. I informed the power company that I was going to have an electrician out and I was going to pull the meter and check the connections. We did and the lineman gave me a funny look when he arrived and saw that we cut their lock/clip. He understood. I have good confidence that the lines to my service and panel are now tight. The electrician installed new clamp connections on the neutral at the top of my service pole and the top of my weatherhead. We also tighted all the neutral connections in the panel. So, this answers the question about the meter check and tightening. The transformer and neutral on their pole was to be checked by the last lineman that was out. I haven't talked with him, but assume that the transformer would be changed if he found a problem. I think this answers the transformer breakdown question. Could the transformer be "quirky" and be random like this?

To further answer questions above:
Have you (I) seen outages on 240 volt devices? I haven't monitored those circuits individually other than watching my pump start and run amperage. It was in normal range. As I stated before, I turned all 240 circuit breakers off for a day and still witnessed these glitches in the system on the 120 equipment circuits, so I thought that this eliminated those circuits from possible causes. My pump was my first suspect, given the amperage draw it takes at start up. Could a loose neutral in the well still cause these glitches if the circuit is off? See, I don't know electrical very well, but I can design a bridge if needed.

Here is more information that I failed to share. My first inclination was to blame the power company and I'm still not completely convinced that it is not them. As I stated we live in a rural area and there are a number of center pivot irrigation systems (ie big pumps and electrical systems). So, I thought Hmmm? These problems started occurring more when irrigation in the area started in late May and have continued. In order to operate these center pivot systems they need to pump plenty of water and power the drive systems. The glitches that we see are typically betwee 5 am and 9 am and at night between 6 pm and 10 pm. This is during period that we use our systems also, but we are small fish in the power grid. Does this sound like an irrigation system schedule. YES it does, so I'm still suspicious.

Some strange items about my system:
Some of the house was built in the 1940s, but the wiring was added later. It is all copper in the house. Some of the old system is two wire (10 ga.), no ground. Additions to the home were made in the 70s by contractors with questionable character. I can tell this by the structural work they did. Very poor. I'm not confident that I don't have a loose wire in the house distribution system, but this doesn't explain why I have a glitch throughout the house in both two and three wire circuits. That's why I am not chasing individual circuits yet.

The ground is grounded to the old water pipe system that is under the house. It is a slab-on-grade house. I said "old" pipe system because I have abandoned the use in this system and have gone to a PEX water system. So the water pipes are all cut, capped and isolated from my current water system. Is this suspect?

Also, both the power company and electrician gave a hmmm? Look at my service drop. The neutral sort of passes by the service connection. Bare with me when I try to explain this. It isn't wrong, but it's different and not common as they explained. The neutral come overhead from the transformer pole to my pole and is clamped to an wire that comes down the pole to the neutral bar in the disconnect and meter. Sounds normal, but it is also clamped to the neutral at the top of the pole that feeds to my weatherhead. So, the hot legs do come down the pole in conduit through meter then to my disconnect, then back up the pole (separate conduit) then over to my weatherhead which is normal. Like they said "that's different way to feed the neutral".

1) My next move is to bring in my own monitor (with an electrician) to confirm or contradict the power company. As I stated, the power company did not monitor the neutral leg. I will.

2) My equipment is important enough to me to install a TVSS to protect from surges. We are in a lightning prone area so this is prudent. Any suggestions about a brand or type of TVSS? I researched them a little bit and am opting for a Type C whole house TVSS? Is this correct? A TVSS can't hurt anything and I was quoted an install cost of $300+\-. Is this reasonable? I know there is a large difference in quality as some or all are made in China now.

3) I think I may install a new ground rod. The problem is that I would like it close to the panel but would have to jackhammer through the slab to get to soil. Any thoughts on this?

This is a good mystery. I am doing my best to protect my critical equipment with battery backup/conditioners. My less critical equipment is protected from surge, but not low voltages, which is more dangerous.
Keep feeding me ideas please. I appreciate the help. I will keep you informed of the outcomes.

Excellent post, I breezed through it, and certainly have some comments, just don't have time right now, be back as soon as I can.

How is your main breaker and the buss it connects to? a bad Hot leg/connection could produce problems with 240 and 120 volt circuits.
Have you tried measuring from your hot feeds and the buss, should be 240 volts or zero. If the zero measurement shows a low voltage, there is resistance with breaker, buss, or wire connections.

Thanks all on the comments so far.
It's Saturday and I'm not going to get an electrician until Monday morning. I'll double check the resistance through the Main along with the other items I'm going to do. Sorry I wrote so much, but there is a lot to consider in this somewhat common problem. It just seems like the usual stuff isn't working, yet. This is why I'm still suspicious of the power company's supply.

I'll await more posts.

Certainly appreciate the detail in your post, Outstanding.

However, you really don't say exactly what the symptoms are. Surges? Do lights blink dim or get bright?

Resistance testing you need to de-energize.

You can use the 87, I believe it can measure millivolts, so across any live connection or device, say the Main Breaker, if the mV drop is more than 100 mV, there is a problem. Shhh, trade secret to confirming and quantifying a heated connection found with IR.

But let me get back to what I find interesting, the irrigation schedule. Can you find out what the HP is of the pump motors?

Large motors can be sending you surges. 20, 50, esp 100 HP.

Being so rural, the condition of the local grid may be part cause, but the pump schedule seems to fit.

TVSS is a great idea, but I think you will still see issues. Brands are pretty much the same nowadays. Get the highest clamping voltage you can afford. Stick with well known brands, such as Square D, GE, Siemens, APC, Mission Guard.TVSS should be at multiple levels, Main Panel for sure, also any subpanels, and at the receptacle or device level. Never rely on just one level of protection,as some transient voltages are created frm within.

Really need to know what symptoms you are experiencing.

Another ground rod is always a good thing. I use a rotary hammer and drill a 3/4" hole thru the concrete floor, as long as there is not a high water table, and drive the 5/8" rod through the hole. Be sure to be at last 6 feet away from any other rod or grounding electrode.

You say your using for a grounding electrode an old water line? This does need to be supplemented with a rod to conform to code. Been that way for many years.

A recorder will help with direction to look for problems.

Thanks.
It looks like you hit all the items and replied just as I thought. I know an electrical engineer that would have responded exactly as you. Hopefully your not offended by that, he is very bright.

It is hard for me to describe things I don't understand. The Civil Engineering is showing through in me. The battery back-ups that I have audible indicators when there is an outage. Good question on the surge though. I use that term loosely. I am now suspecting that these surges aren't surges at all, but they might be under voltage. I'll try to describe what we are seeing and tell me what you think. The lights don't "blink" or have brightness but they exhibit a small down draw as if a motor is starting up. Most of the times we witness this it is during waking hours so lights aren't on. The TV and audio equipment is on a battery backup. The battery back up will beep or click for an outage or a surge, respectively. The TV audio will pause for 1 or 2 seconds. The picture continues to show, but the sound is lost and the battery backup clicks. I have a hot tub, but it is offline, meaning the breaker is off, the subpanel breaker is off, the wires are disconnected and the tub is temporarily moved of its foundation. It has been offline since April+/-? When it was up and running, I also recall that the control box would chatter sometimes for several seconds and then resume to normal. Not sure if that was related. I'm rethinking the word "surge". It could be a voltage dip?

This brings up another point from the power company. They have a copy of the monitoring report and I should have it next week sometime. My friend at the power company is going to hand deliver it. He described this spike amperage draw (30 amps+/-) and said that my panel was unbalanced because with that spike their was a significant dip in voltage on one leg (85 volts) and surges back up to 140v. At the time I didn't question him, but this brings up the chicken and the egg question from the civil engineer. If the power supply drops to 85 volts, then my equipment, motors, etc. of course is going to try to draw more amps? Correct? I'd feel really stupid if I were wrong, but I want to see the printout and ask that question. I'm not confident that he knows, because he might of well suggested a loose neutral as a common problem. Given it is a rural area there is a small pool of experts in the electrical power companies and politics is the way folks advance, knowledge aside.

I forgot to tell you that the electrician had a IR thermometer and checked all the breakers for heat. I don't recall if he checked the main. I can/will do that first thing.

I had the same thought on the ground rod. I'm no stranger to the roto hammering and my slab. I am considering changing over to a new ground rod completely and abandoning the pipe ground, although the old pipe system could act like a Ufer ground couldn't it?

Now more speculation about the ground. We have no ground water, but soils are partially clay. If the clay is very dry, is it possible that the grounding capability is lost or diminished? Clay contracts during the summer and there could be a separation from under the slab. We've owned the house for about 10 years and have been working to improve the water drainage away from the foundation/house. Could I have dried the clay soils so much to several the bond of the ground?

I might be able to find out the farmer's well pump size at the well closest to our house. The farmer might get suspicious if I called him and asked, but if it is a turbine pump the motor should have a plackard on it. He doesn't live very close to this field so I can approach the wellhead without suspicion. If it's a submersible, then I'd have to look at the above the ground controls or capacitor box. I assume it is going to be big enough to have motor starters and probably some pump protection. The irrigation wells in this valley are required to be deep, >800 feet, so it is going to be a "big boy" of sorts. There are several wells in this valley that are greater than 2000' deep, so don't be shocked if I find out it's huge. The well that is closest to us is irrigating mint, which requires neary constant watering. I'm also considering adding some pump protection on top of the TVSS. Like our electrical engineer, you've recommended multiple layers/levels of protection. I understand that the TVSS is probably not going to get everything, but it will get some.

I've left more questions than answers again.

This has been a fascinating thread.

I have a suggestion, You know when the times are, so can you disconnect your entire house for a few hours and do voltage monitoring on the power line?

If it's there without you connected, it's the transmission line?

It does seem like a "regulation issue" which may boil down to somemthing undersized or even a bad connection somewhere on the power grid.

Transformers cab "break down" in an intermiitant fashion until they finally fail. Typically this might be seen as a sudden drop in voltage too. However it should be very quick event.

This link does confirm large motor sizes from 3-200 HP for irrigation. Mid-Atlantic Irrigation | Quality Agricultural Irrigation Products | 888-442-0240 (http://www.irrigationparts.com/products/berkeley/berkeley.aspx)

Looking through the Berkley catalog I only found motor to 2.5 HP
Anything higher than that seemed to use an engine driven pump.

Itink your' overprotecting yourself and your equipment because there is something wrong with the utilities's distribution.

So, as I said live without power for a day and run a capturing recorder. Easy to do. Shut off the main disconnect and monitor there.

Definitely do the recording ASAP, best to do at the MCB , but with all load on running normal. If possible, do another recorder at some critical device, well pump perhaps. Or at a UPS unit. I have 6 of one type for just such occasions.

A large draw elsewhere and one bad connection on the grid can cause a voltage sag, undervoltage, as opposed to voltage swell, overvoltage, or transient, short bursts of abnormal high voltage, 1-2 KV for a few cycles.

The voltages you do mention are indicative of a loose neutral.

In therory, Ohms Law states that amps rise while voltage drops, but an appliance will stop working properly with voltage out of tolerance, so the real amp draw is not an issue.

Why not just ask the farmer for the info. If you having problems, he may be also.

If the motors are large, the utility should also know, so they can size overhead lines , transformers, etc. to handle large loads, and give reliability to other customers.


I had a annealing shop with large electric furnaces coming on a 5 PM every day. My service call was at a local tavern, for real, with a fancy computer driven liquor dispenser. It would not work properly. 5 PM was Happy Hour!! The utility had some poor connections, and did not design the local grid for the load and did some rewiring.



Most if not all states have a Public Utilities Commission that keep utilities on their toes.

Dry clay can be a poor ground. When you get an electrician,ask for a ground rod, ohm meter to measure the ground, should be no higher than 25 ohms, for a safe ground, closer to ten or lower depending on any critcial equipment.

A ufer is a concrete encase 20 foot long. You old water line is a fine addition to the system, just needs to be supplemented with a rod, maybe more. In Maine, the min is two rods, no matter what.

For problem locations, there are chemical assisted grounding electrodes.

An infrared image and an Ultrasound detector may find a problem transformer. US works great for poor utility connections also.

Most electricians will not have all the instruments I mention, some may have some, but not all.

Okay. Possibly more advice needed based on new information.
I brought in another electrician. He immediately noticed items that the other electrician did not notice. Let me know if he is accurate. Recall the description of the service drop from above. The N wire coming down my conduit to bond to the N bar is of inadequate size. And, the N wire into the panel is of inadequate size. Hence, this will require me to change the wire (I'd guess 80 feet), the weatherhead, up size all the conduit to 2-inch in the house to the panel, etc. Cha-Ching$$$$. Does this seem like it could be causing the symptoms? I thought so, but recall I'm a CE not an EE. He is giving me a quote for that set of improvements. He lets me do as much of the work as I can to save me his labor costs.

He left me a spool of bare copper cable for running my new ground out to the perimeter of the house and an 8-foot ground rod. I'll rough it in and let him finish. Thankfully, he is going to loan me his roto-hammer so I can install it myself without busting an egg bag. He will do all the connections and recheck the neutral bar etc. of course.

Once the ground is installed, then we will do a 3 days of monitoring at the service disconnect outside and at the panel inside, simultaneously. I think it will include a night of having the entire service turned off so we can see what I'm getting from the supplier.

I'll have him check the main when he returns to finish the ground.
More later this week.

It is/was common to use a smaller neutral, as it handles the Unbalance load.
It only handles the load difference of all your 120 volt circuits, 240 stuff is not a load on the Neutral.

Without know what size wires you have, and what size is proposed, hard to speculate, but Strat is correct that reduced neutral was popular.

Quite frankly, I think it is bogus to replace parts, without doing testing first.

But again, not knowing the sizes, I may be all wet.

Adding to and otherwise supplementing the grounding is fine, if needed, which I do believe.

Doing a recording, and being sure to measure neutral amps, will show the reduced size neutral is probably sized fine. Connections must be checked thou, and must be grounded properly.

Photos would help.

Wondering what ever happened here.

Did it get resolved?

Were we correct, or were we all wrong?

We're still working on this darn thing. The "good" electricians are busy in this area. Amazing in this economy.
Anyway. We installed a new ground and separated from the old grounding system, at least for a few days. Ocilliscope monitoring showed some minor variations on one leg. We are monitoring this "noisy leg" at the service drop and monitoring both legs at my panel. He didn't have the proper clips to attach the ocilliscope in the panel and my panel is quite messy. We are going to monitor and compare voltages over the next 24-48 hours and see if the ground change made any improvements. We are still suspecting the undersize neutral wire is our culprit, but not sure yet. It has all the signs of a loose neutral, but nothing seems to be loose in any of the panels. The panel is solid. The main breaker is a Hanson brand? And they have changed them out in the past for similar circumstances. The resistance across the main was near zero, so that may not be it. If it heats up, then it might be worse, but for now we have ruled it out. The neutral has 4 or 5 connections between the N bar and the service drop. This is another bad situation. My next step is to replace all the wires from the service drop to my panel, going underground to the house. Something I've always wanted. At the same time I will add a Cutler Hammer CHSPD Ultra TVSS at the panel and install a manual transfer switch for a backup genset. This won't help a loose neutral in the panel, but for the cost it is worth the expense while I've got things torn up. Any experience with TVSSs?
CH brand is pretty good and this model is the largest residential one that they make, without having to change the panel.

More to come in the next week.

Thanks for getting back. Everyone here needs the feedback.

Best to use a DLRO, Digital Low Resistance Ohmmeter on contacts and bolted connections.

Did you try measuring the millivolt drop across critical connections? I thought the 87 did mV. Load the service with as much as possible up to 80%, and any connection .100 mV or over is questionable.

Be sure that any metal piping or mechanical system in the home is bonded to the grounding system. To include telephone, CATV, and any RF antenna. Check with local gas company if their lines can be grounded, intentionally.

I question separating and not connecting the old grounding system.


CH TVSS works fine, get the highest clamping voltage you can afford.


A reduced neutral, properly connected, does not cause any of the symptons you seem to have.


What kind of variations? What is the variable?

Define noise.

Keep us posted.

Many contractors, like myself, had to cut back, and are now getting spurts of brisk business. And everything got to be done NOW.

Feast or famine.


Ummm, who is "we"?

Today's Civil Engineering definitions of electrical lingo-
We = my wife and I (and now an electrician). You are included also. I don't want to leave anyone out.

Noise = one leg appears to have voltage fluctuations 1 to 2 volts relative to the other leg.

The electrician brought in his megger, I think it was a Fluke also. He checked the main breaker with the megger and found the resistance to negligible (like .05 ohms).

He and I checked the service, meter, and connections at the top of my pole again. This is the 5th set of professional eyes looking at this. 2 from the power company and 3 electricians.

He and I turned off all the breakers and added one breaker at a time and used the Fluke 91 (ocilliscope) to check the voltage drop as load was added. I turned on equipment, lights, etc. in the home and we watched to see if either leg was effected. All appeared normal and we did not experience an event during his visit.

We plan to reconnect the old piping system when we complete the monitoring. I believe it is code to ground all these systems if possible.

So far the monitoring has shown me that we are not getting significant voltage drops during these events. The voltage ranges are between 114 and 125 volts.

I think you hit the key words "properly connected neutral" with that many splices/connections I'm suspecting trouble.


Don't worry I will find this problem, if it kills me.

Aw jeez, a husband and wife team working around the house. I hope I don't see you at our Relationship board after this.

A Megger test on the circuit breaker? First I ever heard of that.

A megger is designed to measure millions of ohms, not milliohms. A megger creates and supplies high voltage into conductors, and measures the hopefully high resistance of insulation. If that unit is not a DLRO, then it is a rounded off number as the meter probably does not go low enough.

Maybe your not sure what the test equipment is.

Without a recorder, chances of catching anything real time is slim to none.

What happened to the possible large motor load down at Farmer Brown?

Anyone checking connections at the utility transformer, both Line and Load?

Getting anywhere with this?

Like reading a book and find the last page is ripped out.

Is there anybody out there?
Need sound on...

K8E_zMLCRNg

SOLUTION FOUND: Sorry it took so long to find the solution and get it posted. I JUST got through it last week. I talked the power company into changing the transformer, that wasn't it. I replaced my service line that was undersized and had several splices, that wasn't it. At the same time, I upgraded and installed a transfer switch panel and TVSS. That didn't help, but I didn't think it would. While I was doing the change over, the power company monitored the service. The finally admitted IT WAS THEIR PROBLEM. They were seeing 86 volts at times (for a period of one or two seconds). They (the lineman and supervisor) decided to change my service to another phase. Thank you. Problem was immediately solved, for me. I've given as much information to the power company as possible for them to try to locate the issue. They are monitoring other locations and looking for a Hot Tap (bad connection) on their side. I suspected this all along. Many of you supported this. It has cost me about $2400 in monitoring and improvements, but I'm not bitter. It was service upgrades that I needed and wanted. I lost only one minor appliance with a transformer. Maybe $20 worth for a special clock radio. It needed to be upgraded also.

The power company denies that it is a local water pump, but I'm still suspicious. They thought that the occurrence could relate to wind events, I told them that this was not the case, because I documented time, date, and noted conditions. I wish them luck and I would hate to be on that phase until it is fixed.

Advice for others with this problem. 1) Identify the scope of the problem quickly (whole panel or single circuit) If it's a single circuit, then go box to box looking for loose neutrals or grounds. 2) Get monitoring with a professional quickly. Utilize multiple monitors on your side of the meter, the power company's side and at your panel. 3) Document the time, dates, and extent of power loss or voltage drops. 4) During the monitoring eliminate (turn off) all unneeded circuits to try to isolate the issue to 110 or 220 circuits. 5) If need be, write a letter to your power company documenting your issue and the costs and ask for help. (Luckily, I didn't need to)
6) Be sure that your service is clean and tight during monitoring and protect your valuable equipment. (fine electronics, pumps, motors, etc.) Electrical safety is important to you, your family, and your equipment.


A BIG Thanks to all that posted comments. Your support was great and helped educate me on my options.

Thanks for getting back on this problem, and putting up with my harassment trying to get a response.

Hmmm,where did I hear " do a recording first" before?

I added this thread to a Read First - Best of post to share this info to more people.

Good stuff.

I have a similar problem with surges and outages. I've had the local power company check their service and intall a monitor. However, they don't monitor the neutral leg. They told me the problem was on my side of the panel and I had a spike draw of 30 amps and unbalanced voltage during these times. They saw a problem on both hot legs, leading me to believe that it was isolated to my 220 equipment, which is limited. I started by turning off all the 220 circuits, but I still experienced the problem. I then had an electrician come in and tighten all the neutrals in the panel and the power company check their neutral connections again. Things seemed okay for a day or so, but it is back. What do I do next? Isolate each and every circuit? The surge/outage appears to occur throughout the system, which leads me to believe it is in the panel. Okay, my theory is that in very dry soils, like now, the ground is no longer truly grounded. Is this my next check?

Have you asked anyone else near your building if they were experiencing similar fluctuations?

Have you asked anyone else near your building if they were experiencing similar fluctuations?Just to note:

The original post is from August of last year.

Also, the last reply by the original poster, made in Oct of '09, was that of thanks for the help since he has found a solution.


New folks, PLEASE read all the posts and check the dates before replying.