Water Meter Woes

Major thermal event today after 4 totally uneventful months. Under mysterious circumstances however. Today the City knocks on my door asking to change my water meter to a new electronic sending type. I show them where the meter is located and let them go about their business. Go back to my audio system that happened to be on, and , multiple tubes red plating. Can hear a loud hum and also detect faint smell you associate with over heating.

Seems beyond coincidence this should happen at the exact same time the City is changing out the meter. About a foot from the meter there are two heavy duty copper wires clamped to the water pipe. These lead to my electrical panel. Some kind of surge maybe? Once things have cooled sufficiently will go back and check for damage. Sigh.

A couple of things come to mind:

a) Your previous water meter was not 'Bonded'. A water meter serves as a point of high resistance in a copper water system. What this means is that if an unbonded meter is in a water line, any system grounds connected on the load side of the meter will have less ground potential than those connected on the line side of the meter. US Code no longer recognizes a domestic water system as a reliable ground, but still requires meters to be bonded (bridged) and breaker/fuse panels to be connected to the domestic water system if copper and on a municipal system.

b) The meter installers, observing this condition responded (probably) per local codes and either bonded the meter, or installed a ground from your panel directly to the line side of the water service.

c) Not only would this cause a surge at the moment the bond was made, but could also increase your voltage at the wall-plate, possibly significantly.

NOTE: The water company did nothing wrong - they may, in fact, have corrected a dangerous condition, *to you*.

At this point: Determine the voltage at your wallplate. If you know *exactly* what you are doing, determine the Line-to-Line and Line-to-Neutral at your panel. Now measure Line to Ground, and Neutral to Ground. If you have _ANY_ reading over a tiny amount on this last reading (Neutral to Ground) you have a problem. Before I elaborate on what that might be or ways to correct it, please check and report back.

Turned the amps back on, finger at the ready to turn them off ASAP at first sign of distress. But after an hour all tubes are glowing normal, and no more loud hum. Totally bizarre, and highly unsettling. Is one of those Furman things the only answer?

Thanks for the suggestions Peter but the only thing I know how to check is the wallplate. Showing 122v.

My closing advice, if the water meter guy knocks on your door telling you its time for a new meter, run to turn off your tube amps!

Note the interpolations

LeGrace wrote:Turned the amps back on, finger at the ready to turn them off ASAP at first sign of distress. But after an hour all tubes are glowing normal, and no more loud hum. Totally bizarre, and highly unsettling. Is one of those Furman things the only answer?

Not the only answer, but a very good option. Also "Compensated" Sola CV transformers -at a cost.

Thanks for the suggestions Peter but the only thing I know how to check is the wallplate. Showing 122v.

Too high in my opinion. I am probably one of the few Americans who has some familiarity with the Canadian grid. A few things: Canada runs high in line voltage as where there is electric heat and huge demand this time of year, running the grid at the high end of the tariff reduces brown-outs, and overheating transmission lines. I have seen as much as 130V on the grid-tie transformers at solar farms my company installed all over Quebec.

My closing advice, if the water meter guy knocks on your door telling you its time for a new meter, run to turn off your tube amps!

Good advice when anything is being done anywhere in your domicile that is incidental to the electrical service.

Maybe the ground was removed while they were swapping the meter. Do you have a ground rod going to the meter too?

Something else to keep an ear out for - some folk have experienced noise issues due to RF interference when the meter tries to "call home".

Progress - ain't it grand?

PS - ANY red plate event will shorten tube life. Be interesting to see how many more hours you get on yours even if they are playing nice now ...

Oh. Too late now, but wondering if one of those GFCI adapters that require a manual reset on any power event or interruption would have saved the day? The red plate you experienced would be an indication of fast cycling without allowing the amp to discharge properly.

https://www.amazon.com/TRC-90033-Shockshield-Portable-Protection/dp/B000XVG72G/ref=sr_1_6?ie=UTF8&qid=1515606076&sr=8-6&keywords=gfci+adapter

I do have a manual reset GFCI. But it didn't help with either of my last two red plate episodes either for that matter. Only seems to trip when there's a  power outage. Previous red plates have been limited to the rectifier. This is my first time red plating the rectifier and multiple power tubes all at the same time. What a sight! Poor old GZ37's. My tube amps might burn down the house paranoia had faded over the past few months but is back with a vengeance. Electricity is amazingly powerful.  

Where the ground wires are clamped to the water pipe looks like corroded battery terminals. Significant oxidation buildup. So today I sanded everything down to nice and shiny copper then tightened the clamps back up. Wall plate is down to 119. Also replaced the power tubes on one amp. Will be watching things closely, again.

Which side of the meter are the bonding clamps placed (house or street)?  If the clamps are on the house side of the pipe removing the meter could briefly disrupt ground until a new meter is connected.  120V could vary greatly in this case.  They should connect a bypass jumper between the pipes before making the meter swap.

The bonded AC neutral close to earth ground potential is your connection to the center tap of the electrical transformer split phase feeding your place.  The transformer center tap is also connected to earth ground as well to make the connection complete.  This all has to be low impedance to keep line voltages stable.

Temporary loss of ground seems the most likely explanation then. Curiously my stepson did this exact same job for a year (contract position) in Toronto. So I asked him had he ever connected a jumper while changing a meter. Answer was never. Wasn't part of the training.

Per the NEC:

Water Meters feeding from Municipal or Central underground systems must be bonded. This means a piece of #8 or better copper wire across the meter to create an electrical path should the meter be removed, become damaged or no longer conduct.

If the main system ground is on the Line Side of the meter, bonding is not required if it has been verified that there are no secondary systems grounds in use (Secondary grounds include POTS systems, cable systems and so forth).

Since about 1970 +/-, separate ground rods a minimum of eight ( 8 ) feet long driven so that no more than six (6) inches remains above grade must be installed in addition to any other grounds.

I once lived in a house where, unbeknownst:

a) the Utility Neutral failed.
b) The drive ground rod (location was a former quarry) was every bit of 8' long, but must have been driven by a jack-hammer as it bent and went sideways from about 2' down.
c) The existing water service was quite-vintage galvanized iron pipe.

One day, we had a small geyser at the curb-stop and had to replace the water-service. The excavator dug to the curb-stop and and cut the pipe - BIG spark and the house went dark. I cut the service at the main - very fast! We called the Utility, and they graciously came right away and re-made the bugs at the service-head so we could get power back. And equally graciously, they used one of their *very large* rotary drills so we could set a proper ground rod. They did not supply the rod, but they did take the old one as an object lesson for newbies.

Anything can happen about anywhere, about any time.

My house also had a grounding rod plus water pipe connection. The cold water pipe connection was added in 2010 when solar panels were installed (up to code). That new cold water pipe ground improved my electricity service so much. No more lights dimming when when other things are switch on in the house. Line voltages were much more stable afterward.

Really interesting responses. My SS integrated wasn't the least bit ruffled, operating calmly sitting next to my tube amps throwing a hissy fit. But I can understand why a meter change like this normally would be a non issue in 99.99% of homes, as so few devices in a home are this voltage sensitive. Just my luck the amps were on when they arrived.

Jumper across the water heater from cold to hot too.

cci1492 wrote:Jumper across the water heater from cold to hot too.

Being a belt/suspenders/Velcro type of person when it comes to life-safety. we have jumpers to the gas main, heating risers, across the water storage tank (indirect heater from the boiler) and from the ground-rod to the line side of the water meter.

The bed? Don't tell me you forgot your bed!

cci1492 wrote:The bed? Don't tell me you forgot your bed!

Oh, I dunno... .

cci1492 wrote:Jumper across the water heater from cold to hot too.

Just looked and to my surprise I see a copper jumper! New water hater, only 6 months old. Changed at the same time they red tagged my furnace.

Technically speaking, when the water pipe ground was removed, you should still have the ground-neutral from the pole (not the check, the pole).

cci1492 wrote:Technically speaking, when the water pipe ground was removed, you should still have the ground-neutral  from the pole (not the check, the pole).

That's Czech.

I feel so lucky here in the UK with a 230(240)V single phase supply and a stable line voltage. No split 120's to imbalance the local transformer. We do have various earthing techniques (TN-C / TN-C-S / PME) but nothing like you guys have to endure.

Of course the local feed is single phase and it is up to whoever connected the utility supply to adjacent houses to balance the load on the main 3 phase lines.

Generally our water and gas feeds are brought to our properties by plastic pipes so any internal bonding is to ensure all items in the house are at an equipotential should a fault occur. With our regs the need for cross bonding is not so stringent as long as RCCD's (GFI's) are fitted but I like everything to be cross bonded as I don't like relying on a device made in the far east for my safety.