FIRE! What was supposed to protect me from this?

[wyliesdiesels]

@wyliesdiesels



Sorry for the crappy zoomed pic didn't have shoes on to walk across yard

are you referring to the cutout hanging off the porcelain insulator? if so, thats on the HV primary side. that doesnt protect individual drops or services

please show me the cutout on the secondary side feeding the drop to your house.

 

[PCustoms]

are you referring to the cutout hanging off the porcelain insulator? if so, thats on the HV primary side. that doesnt protect individual drops or services

please show me the cutout on the secondary side feeding the drop to your house.

That's not what you stated when I responded:

only way to have that kind of protection would be to put breakers on the poles for individual service drops. would cost a fortune

If you meant on the secondary side you should have said that


That comes off the line and feeds the transformer that feeds only my house. So it's there for the individual service drop

 

[kaymccampbell]

Well good thing thats all the happened

may not be connected, but

when I was in charge of the facility, any time electrical work was done I required a thermal camera inspection of any panels that were worked on.
the electricians always said it was not needed but I insisted (and we had a thermal camera on site). It’s amazing how often they found hot spots and ended up tightening lugs

Ooh, good idea. My new thermal cam, that I used to check water tanks for waterlogging, will come in handy here. I imagine there will be a bit of tightening. Time to go a-testing.

 

[mm08822]

That's not what you stated when I responded:



If you meant on the secondary side you should have said that


That comes off the line and feeds the transformer that feeds only my house. So it's there for the individual service drop

"for individual service drops"

The primary fuse for your house only is protecting the transformer and preventing a nuisance outage to a larger customer base. The fuse will not protect the secondary conductors as you are expecting.

 

[PCustoms]

"for individual service drops"

The primary fuse for your house only is protecting the transformer and preventing a nuisance outage to a larger customer base. The fuse will not protect the secondary conductors as you are expecting.

I'm not expecting it to protect my house


We're going in circles, I'm done

 

[Stuart in MN]

Not sure what you meant by cutouts, but the current version of the national electric code calls for a main disconnect switch at the meter on the house exterior for new installations. If there's a fire inside the house, the firemen can disconnect power before entering. Not all states are using the current NEC, so this may or may not apply depending on where a person lives

 

[mike93lx]

Not sure what you meant by cutouts, but the current version of the national electric code calls for a main disconnect switch at the meter on the house exterior for new installations. If there's a fire inside the house, the firemen can disconnect power before entering. Not all states are using the current NEC, so this may or may not apply depending on where a person lives

That wouldn't have helped here

 

[dave*99]

The first point of over current protection on the secondary of the power system is your main breaker.

It might be a meter main or a main in your panel etc.

The POCO does not always protect the secondary side of the distribution transformer, and your service drop is connected to the secondary.

So whatever energy that transformer can pull from its primary fuse, transform, and pump down the service drop is available and sufficient to melt your meter pan internals.

 

[DGersic]

You said the same extinguishers tasted horrible.

How much of the powder did you inhale/ingest? Yiu should probably get checked by a physician if you did.

Just be glad you were there when it happened.

Not much. Just got some blown back by the breeze.

 

[DGersic]

OP, remember to replace/recharge those extinguishers NOW!! You owe them big time!!!

Already done. Got two new ones. And a new smoke detector.

 

[Cruzan80]

This is a good time for a PSA...

Not all fire extinguishers are equal. Make sure you get a kind rated for what you are trying to extingush!

None of this was meant specifically at the OP, just general FYI. Glad to hear it ended "Not as bad as it could have been".

 

[Junkman]

Not sure what you meant by cutouts, but the current version of the national electric code calls for a main disconnect switch at the meter on the house exterior for new installations. If there's a fire inside the house, the firemen can disconnect power before entering. Not all states are using the current NEC, so this may or may not apply depending on where a person lives

How do firefighters handle homes with generators that automatically start during power interruptions? My generator is located inside the last bay of my garage and is connected to the house service by an ASCO 185 Series 200 Amp Automatic Transfer Switch and a Lister Petter 4-cylinder 18 KW generator. Power goes out, and 15 seconds later, the generator starts up, restoring service to the home. When the power company restores power, the switch switches back to line power, then a 2-minute cooldown for the generator starts, and the generator shuts down.

​

 

[NUTTSGT]

I've said it before, Chapter 13 of Murphy's Law is "Fire". If it wants you, it's going to get you no matter how you try to protect.


OP, one of the first things I say to homeowners/tenants is that nobody got hurt and it's good it happened "now" rather than at 2am.

@Junkman
As far as standby generators, solar panels, and mass meter pans (like an apt bldg) it's pretty much a case by case basis. Depends on who is OIC, time of day, can POCO remote disconnect the service what is burning and where.
Sometimes, you have to make split decisions at a million miles an hour and hope nobody gets hurt. Err on the side of caution, risk a lot to save a lot, risk little to save little.

 

[William Payne]

It probably exists and I just don't know but I am surprised nobody has thought up some kind of thermal disconnect where once it gets to a specified temp it shuts off supply. There must be a reason nobody has done it because if my layman **** can think it up, actual smart people have surely already thought of it.

 

[PCustoms]

It probably exists and I just don't know but I am surprised nobody has thought up some kind of thermal disconnect where once it gets to a specified temp it shuts off supply. There must be a reason nobody has done it because if my layman **** can think it up, actual smart people have surely already thought of it.

Google Search

Or think of the little red thermal trip on the back of a motor

 

[William Payne]

Google Search

Or think of the little red thermal trip on the back of a motor

Thanks. I did a bit of a search after I made the comment. Surprised it’s not more common for situations just like the original poster experienced.

 

[DGersic]

It probably exists and I just don't know but I am surprised nobody has thought up some kind of thermal disconnect where once it gets to a specified temp it shuts off supply. There must be a reason nobody has done it because if my layman **** can think it up, actual smart people have surely already thought of it.

You’ve rediscovered the fuse. Fuses and breakers are heat sensitive devices. The fuses installed at the transformer did, eventually, shut down rhe power, but are there to protect the transformer, not the wiring between transformer and house.

That’s something I’ve learned from this.

The breakers in the house protect the wiring in the house. The breakers (or fuses) at the transformer protect the transformer. Nothing protects the wiring between the transformer and the house.

Could there be? Seems like it’s possible, but more expensive, so it’s not done. So, good luck, hope nothing g goes wrong with that.

 

[mike93lx]

Thanks. I did a bit of a search after I made the comment. Surprised it’s not more common for situations just like the original poster experienced.

It's a rare enough occurrence that no one would choose to install them, then the manufacturer would lobby for a requirement in the NEC, then we would have something new to ***** about because installing a new service just got $2k more expensive

 

[larry4406]

... Nothing protects the wiring between the transformer and the house.


Interesting...

 

[Jlanciani]

Some utility transformers have secondary breakers;

A Completely Self-Protected (CSP) transformer is a distribution transformer with integrated protective devices—including internal high-voltage fuses, secondary circuit breakers, and lightning arresters. These units, often pole-mounted or pad-mounted, prevent transformer failure from overloads and surges, minimize fire risks, and reduce maintenance costs.
Key Features and Benefits:

• Integrated Protection: Combines lightning arresters for surge protection and internal breakers/fuses to protect against overloads and short circuits.
• Improved Safety & Reliability: Automatically disconnects during faults, enhancing safety and reducing the risk of explosions, while isolating the transformer from the surrounding grid.
• Reduced Maintenance: Internal breakers allow for quicker, safer maintenance compared to conventional transformers that require external cutout switches.
• Performance: Available in both mineral oil and FR3 fire-resistant fluids, with some designs using amorphous metal for higher efficiency.

CSP vs. Conventional Transformer:

• Protection: CSP uses internal breakers and weak links, whereas conventional transformers rely on external, separately mounted devices.
• Installation: CSP has simpler installation because it eliminates the need for external fuse cutouts.
• Cost: While CSP often has a higher upfront cost, it typically offers lower long-term maintenance and fewer replacement costs.

 

[driftpin]

That is fortunate you had the second extinguisher. I suspect you had dry-chem A-B-C powder extinguishers? I am a retired firefighter/paramedic (including other certifications/licenses) and always recommended to people to have a couple of A-B-C dry chemical extinguishers someplace convenient, like somewhere in the kitchen, and in the garage, where you don't need to hunt for them in the event of an emergency.

Plastic valve extinguishers usually are not worth re-filling. If the valve is metal, it may be. You may discover that it costs more to re-fill a metal valve extinguisher than it does to replace it. Remember the extinguishers have a service life, before they need to be re-checked and recharged. I usually just buy new extinguishers and rotate the old one to a vehicle, secured in-place w/a proper bracket, and not just rolling around in the trunk, or loose in the cab of a pick-up truck.

FL Power & Light (FPL) is the service provider in So. FL. We just had a visit about a week ago from the contractor they use to install underground poly-pipe for service conduit, to 'storm-harden' the electrical service for the city (in Miami-Dade Co.). They had a diagonal below-grade lateral borer to prepare for street-side electrical boxes to be installed. I'll be eating popcorn while I wait for the inevitable automobile accidents taking-out the street-side electrical boxes which are replacing the rear of the yard transformers on wood poles, which I suspect will be abandoned in-place for residential power delivery, as they also carry fiber-optic cable.

We had a whole-house renovation about 10 years ago, including a new 200 amp service, and an underground feed from the power-on-a-pole transformer in the backyard, which we had service to our home put underground, as the in-the-air power cable installation to the meter can would be nervously-close to the backyard pool/spa.

I was concerned about the power co. lateral bore below-grade, as we have natural gas and a waste line for the second leach field and septic tank we were required to install for the house renovation. We didn't add any bedrooms, but we have 4 full bathrooms and of course, a laundry room.

The contractor installing the poly-pipe buried conduit from the street-side, used imaging equipment to locate the natural gas line and the waste line to the backyard septic tank and leach field. Now there is a stub-up below the meter can, waiting for the installation of the on-grade transformer boxes to be located at the front swale/R-O-W. We are getting billed of course for the 'storm-hardening,' of the electrical grid, but hopefully the work will reduce the amount of time w/o electrical service like the 2 weeks after Hurricane Andrew in 1992.

Below, the lateral power line boring for the conduit.

 

[dave*99]

Here is a long but informative video on CSP and conventional transformers.

https://share.google/R0gn4nteIJYizUPmz

 

[Codyboy]

It appears to me the initial issue was the top right meter jaw. Bad connection between the jaw and spade on the meter.
It then heated the line wire up , melted the insulation and shorted out against the ******. Burned the neutral in two so then all the fault current went inside to the ground rod but wasn't enough so it then made a path to that other bond to the water pipe system?

 

[Codyboy]

Here is a long but informative video on CSP and conventional transformers.

https://share.google/R0gn4nteIJYizUPmz

Yes we used to use CSP type transformers a lot. And being that type , the switch/breaker does actually shut off only the secondary windings . A transformer of that type would have tripped out in the OPs situation.
We (where I worked) haven't used CSPs in years though as they became a nuisance when the internal breaker got weak or was over loaded. On some CSPs there was a separate switch behind the main switch which was an "overload" and it was used just for that to get it back working in an overload situation and then would be scheduled to be upgraded and replaced at a later date.

 

[mm08822]

Yes we used to use CSP type transformers a lot. And being that type , the switch/breaker does actually shut off only the secondary windings . A transformer of that type would have tripped out in the OPs situation.
We (where I worked) haven't used CSPs in years though as they became a nuisance when the internal breaker got weak or was over loaded. On some CSPs there was a separate switch behind the main switch which was an "overload" and it was used just for that to get it back working in an overload situation and then would be scheduled to be upgraded and replaced at a later date.

Exactly why they aren't common: cost, reliability (complaints), additional maintenance items. The frequency of the OP's situation is too low to justify the 3 mentioned con's.

 

[DGersic]

Integrated Protection: Combines lightning arresters for surge protection and internal breakers/fuses to protect against overloads and short circuits.

It’s not obvious from reading this, but “protects” here means that the transformer is protected from the load (house). This is important to the power company, means their transformers explode less often. Doesn’t do the house any good.

At home, I’ve seen a transformer explode when lines came down in a storm. The resulting short circuit went boom.

 

[DGersic]

That is fortunate you had the second extinguisher. I suspect you had dry-chem A-B-C powder extinguishers?

Yes.

We rent, and are required to have a 2-A:10-B-C extinguisher in the kitchen, conveniently and obviously mounted using the manufacture’s bracket. Also must be currently dated, or tagged from a current inspection / certification. This gets checked during the pre-rental season inspection by the city. So we’ve always had one.

For some reason, my brother got failed on the inspection, because he couldn’t produce a receipt showing when the extinguisher was purchased. This happened a few years ago. So he had to run out and buy a new one, and pay for and schedule a second inspection.

A second time, some similar weird inspector thing happened to him, I don’t recall the reason, but he had to buy extinguisher #3. The spares live in the “attic”, a tiny area above the shower where the water heater is, and a little bit of storage.

We wouldn’t normally have more than the required one, because it’s a tiny house (20’x22’) and storage space is at a premium.

Because I had not yet started the water heater, I had the attic open, and the stuff we store up there on top of the kitchen cabinets. That made it relatively easy to grab the second extinguisher.

 

[Sumboodie]

Glad to hear you got it contained quickly!

Can't beat the asbestos siding when it comes to fire and paint retention.

I'm just a bit south of you. I've got a spare Meter/Main enclosure Let me know if you need it or anything else in the way of tools or temp equipment to see you through the repairs.

I thought those were slate? Had it on a house I rented, was hard to drill to put new nails (a few had broke)

 

[mm08822]

I thought those were slate? Had it on a house I rented, was hard to drill to put new nails (a few had broke)

Asbestos based until the industry changed over to masonite. Either one, had to drill first to nail. They were sold with nail holes for nailing a few inches above the bottom edge.

 

[NUTTSGT]

I'd be interested to know what this is exactly what this is.

Melted insulation ? Insulation and wire ?

 

[mm08822]

I'd be interested to know what this is exactly what this is.

Melted insulation ? Insulation and wire ?

Could be any or all of: melted wire insulation, copper conductor, melted plastic stand-off, meter jaw/lug, steel enclosure, meter hub, conduit. Gravity caused the molten materials to drop. They cooled as they landed randomly.

 

[NUTTSGT]

Could be any or all of: melted wire insulation, copper conductor, melted plastic stand-off, meter jaw/lug, steel enclosure, meter hub, conduit. Gravity caused the molten materials to drop. They cooled as they landed randomly.

Oh, I get that. I'd like to know for possible training purposes for the young guys at the station... possible scenarios/what to look for during investigations.

 

[PCustoms]

Oh, I get that. I'd like to know for possible training purposes for the young guys at the station... possible scenarios/what to look for during investigations.

If you have a fairly obvious electrical fire do you pull in other agencies on the investigation?

 

[dave*99]

I thought those were slate? Had it on a house I rented, was hard to drill to put new nails (a few had broke)

I punched holes in them with one of these years ago. Asbestos was popular for siding in NJ long ago.

It can cut them too.

 

[NUTTSGT]

If you have a fairly obvious electrical fire do you pull in other agencies on the investigation?

Generally, no we don't. Local law enforcement doesn't have any "fire investigators" but they have detectives and they ask us for our input. However, the Sheriff had mentioned it a few times, he'd like to have a fire investigator on his payroll and OPOTA certified.... his hint to me at one time to go get my cert and be on the Specials. If it's a fatal, we're required to bring in the state fire marshall's office.

The insurance company can bring in an outside investigator if they so to choose too. That's on their dime and generally only do it if it's a high dollar loss, suspicous or on our recommendation. I welcome their set of eyes, knowledge, share information and work with them.

Sorry for the hijack.

 

[Cruzan80]

@NUTTSGT , can you remind the rest of us if you are Team Red or Team Blue (Fire Dept or Police/Sheriff)? I know you are a First Responder, just forget which part.

 

[PCustoms]

@NUTTSGT , can you remind the rest of us if you are Team Red or Team Blue (Fire Dept or Police/Sheriff)? I know you are a First Responder, just forget which part.

If he's "team blue" that's a really odd choice for his avatar...

 

[NUTTSGT]

@NUTTSGT , can you remind the rest of us if you are Team Red or Team Blue (Fire Dept or Police/Sheriff)? I know you are a First Responder, just forget which part.

Me . . . Fire, 26+ years. . . . Shift Capt, EMT-B and Fire Investigator.

Wife works for the Sheriff's Office, specifically, Admin ***'t for the Sheriff. She also does the CCW stuff for the County, started as a Dispatcher and still maintains her LEADS and EMD certs.

 

[Cruzan80]

If he's "team blue" that's a really odd choice for his avatar...

I was on my phone, and the avatars are so blurry, it looked like an engine bay...

 

[PCustoms]

I was on my phone, and the avatars are so blurry, it looked like an engine bay...

...of a fire truck

J/k