Melted MCB

[Andrewr3]

Customer reported medium sized storage heater not working. I found this. It melted the case of the MCB adjacent to it as well. I guess it was a loose connection.

 

[SPARTYKUS]

Probably, half the time you can never tell as its turned into... A sticky mess

 

[Badged01]

I found this. It melted the case of the MCB adjacent to it as well. I guess it was a loose connection.

"Loose wires cause fires" so a good guess it wasnt tightened onto the bar correctly -- if at all!

 

[Smudge]

different scenario, but on our site, we use thermographic images to help detect loose connections (through hot spots). We get a lot of these in the factory and i always wonder how close we were to a fire!

 

[Darkwood]

They materials used smudge are fire resistant and will melt or char as oppose to burst into flame, The risk comes when 2 adjoining mcb are affected when on different phases as you can get a dialectric breakdown and a high inmpedence fault can start quickly turning into a short... now this is where you get the bursts of flames

 

[Tiny Spark]

different scenario, but on our site, we use thermographic images to help detect loose connections (through hot spots). We get a lot of these in the factory and i always wonder how close we were to a fire!

We also do this, Along with ultra sonic.
Amazing how many things were picked up over the first few years of doing it now hardly anything is picked up LOL.

 

[Engineer54]

different scenario, but on our site, we use thermographic images to help detect loose connections (through hot spots). We get a lot of these in the factory and i always wonder how close we were to a fire!

Thermographic image camera's can be an absolute god send in large working industrial and commercial installations. Unfortunately they are still way out of the price range of any electrician or small company that are predominantly working in the domestic sector. It's also not just a case of purchasing a thermal imaging device, you also have to know how to use it and know how to decypher the imaging information it's providing.... Reading and relying on the manufacturers instructions provided, gives very little help to be totally honest!!

Hopefully these thermal imaging devices will significantly come down in price in the coming years....

 

[Former Sponsor TM]

You can pick up a very decent thermal camera for the price of a mid-range multifunction tester nowadays. You're correct - a one day training course is a must to become familiar with thermography principles and using a camera.

As copper has such a low emissive property, it can cause very strange readings to the untrained eye. Without thermally tuning a camera correctly, a busbar operating at 25 degrees Celsius could actually be reported as being much higher.....

 

[Tiny Spark]

And they are so much fun to play with

 

[telectrix]

my budget stretched to one of these. simple but does for me.

 

[Former Sponsor TM]

And they are so much fun to play with

Recreating scenes from Predator is a must.........

 

[Lucien Nunes]

The risk comes when 2 adjoining mcb are affected when on different phases as you can get a dialectric breakdown

I've seen this on old Dorman Smith Loadmasters, had a board with a dozen charred and carbonised breakers. a few of which had very little of the case left, they were like breaker skeletons. The original cause might have been a combination of loose terminals and high resistance at the MCB contacts themselves due to corrosion.

 

[SPARTYKUS]

I know a chap who does this as a living - he cited a case (large factory) where for a not inconsiderable fee, he identified several circuits that were 'on' when not required- wait for it- he knocked off £10,000 off their heating bill.


a month!!

theres money in thermal imaging.

 

[ChrisElectrical88]

Was the busbar in the terminal? And was it the correct make of MCB for the board?

 

[Andrewr3]

Was the busbar in the terminal? And was it the correct make of MCB for the board?

Yes correct MCB. "Busbar in the terminal"? Don't understand. The MCB was a pushfit to the busbar and all that part seemed OK.

 

[scotsparky]

Thats a squasre D Qoe Mcb hate them. They push fit and some if reused the terminals spread. same as the old Ottermils,

 

[Silly Sausage]

Probably, half the time you can never tell as its turned into... A sticky mess

A bit like MDJ's rugby programme.

 

[moospark]

Yes correct MCB. "Busbar in the terminal"? Don't understand. The MCB was a pushfit to the busbar and all that part seemed OK.

A lot of domestic, you have to drop the busbar out of all breakers to add/remove. Crabtree load star excepted. Possible to get bar behind clamp if your eye is not on the ball.