Something fishy going on at work today

[Paulus]

I'm surprised this isn't much more widely known.

I have known it for many years, and thought it was common knowledge.

The education system is not what it was.
Also, because the cable is coiled, not only does it obviously heat up, but the power output also increases. Think of the old style coils on a vehicle ignition system. 12 volts go in, but, several hundred come out the other end to power the spark plugs.
Ever had a shock of of a damp or broken HT lead or plug cap?

 

[PK99]

Most electrical plastics are impregnated with Urea so they emit a pungent smell when over heating it is a safety feature a lot of people are not aware of

Are they actually impregnated as a safety feature, or is it that urea is used in the manufacturing process?

 

[figbat]

The education system is not what it was.
Also, because the cable is coiled, not only does it obviously heat up, but the power output also increases. Think of the old style coils on a vehicle ignition system. 12 volts go in, but, several hundred come out the other end to power the spark plugs.
Ever had a shock of of a damp or broken HT lead or plug cap?

Not quite the same - with an ignition coil there is a primary and secondary coil; 12v across the primary and thousands of volts out of the secondary. With a coiled cable it’s just one coil, there’s no voltage or current multiplier.

 

[Ming the Merciless]

Most electrical plastics are impregnated with Urea so they emit a pungent smell when over heating it is a safety feature a lot of people are not aware of

Wee !

 

[captain nemo1701]

Many years ago I worked in a call centre. One of the guys who worked there, let's call him Dave, knew he was getting fired so in advance he put smoked kippers in the intake ducts for the air conditioning at the side of the building.

Nothing much was done initially by management and it turned into a truly horrific smell, spread evenly over several floors.

My late father worked in construction and he once said don't annoy builders...for this reason, the old kipper-under-the-floorboards trick.

 

[Windle]

My late father worked in construction and he once said don't annoy builders...for this reason, the old kipper-under-the-floorboards trick.

These days the builder would need a CSCS card for 'the placing of kippers under floor boards' and a certificate showing that it was obtained from a sustainable source, preferably using local labour!

 

[Nibor]

Wee !

If it is electrical is it not WII

 

[DRM]

The education system is not what it was.
Also, because the cable is coiled, not only does it obviously heat up, but the power output also increases. Think of the old style coils on a vehicle ignition system. 12 volts go in, but, several hundred come out the other end to power the spark plugs.
Ever had a shock of of a damp or broken HT lead or plug cap?

Your getting muddled up with a transformer, where one coil of wire induces a current to flow in the neighbouring coil, the example of a cars coil being a simple step up transformer

 

[Drago]

Are they actually impregnated as a safety feature, or is it that urea is used in the manufacturing process?

The office staff or the extension lead?

 

[presta]

Smelling the plug it was obvious the fishy smell was coming from it

I've got a nose like a bloodhound for sniffing out hot electronics, but I've never thought of it as a fishy smell.

Ahhh,I was overthinking why it gets hot.I was somehow thinking it was something to do with magnetic fields within the coils

There is no magnetic field. The current in the live & neutral conductors are equal in magnitude and opposite in direction, so the magnetic fields they create are also equal and opposite, and therefore cancel each other out. That's how RCD circuit breakers work: two windings that cancel each other out until the live & neutral become unbalanced by an earth leak, then a third winding senses the field and trips the breaker. Winding wire like in an extension lead reel is how you go about making a wire wound resistor that's non-inductive.

Think how an electric fire works.
Wire coiled around an insulator.
Simple.

The same reason an electric fire gets hot. Coiled wire wit a current passing through it has that effect.

Electric fires get hot because the elements are made from resistance wire, and still will get hot if the wire is unwound.

The education system is not what it was.
Also, because the cable is coiled, not only does it obviously heat up, but the power output also increases. Think of the old style coils on a vehicle ignition system. 12 volts go in, but, several hundred come out the other end to power the spark plugs.
Ever had a shock of of a damp or broken HT lead or plug cap?

An ignition coil is just a transformer, and transformers don't produce any more power out than goes into them, because they're passive devices with no power supply. A hundred times more voltage just means a hundred times less current, and hence the same power (less a little bit for losses).

 

[Andy in Germany]

When I worked in a theatre there was a strict rule to always uncoil the extension cables, you could use a loose coil but as others have said, the heat needed to be able to dissipate.

 

[Gwylan]

You’re not overthinking it. Eddy currents,due to the expanding and collapsing magnetic fields, cause heat. The cable can’t dissipate that heat due to being coiled up.

A propos of nothing.
I worked in a place where the call on the tannoy system of "Eddy Curran to porters lodge" meant that senior visitors were in the building. Wondered if they ever understood who or why Eddy was needed.