GU10 vs MR16 - what was the point of halogen MR16?

Ectophile

Risteard said:

Ectophile said:

The lamps in my bathroom are a mixture of 12V MR16 and MR11.  The consumer unit in the house isn't particularly new, so the lights are not on an RCD-protected circuit.  One of the bathroom lights is directly above the bath.

I feel safer knowing that the lights are all SELV 12V, rather than mains.

The two transformers were already in the house when I bought it 12 years ago, and are still working now.  I have changed 2/3 of the lamps from halogen to LED, so the load on the transformers should be well below their rating.

Not sure why you would feel safer, as nearly 20 times the current will be running through the cables on the secondary side of the SELV safety isolating transformer. LED should be run from the mains - you are only creating another potential point of failure and making it less energy efficient.

It's not like you can readily reach the luminaires from the ground.

I'm not bothered about the current, it's not that high.  It's the voltage that electrocutes you.

And I'm only average height, but I can reach the ceiling to change the lamps while standing on the floor.  It's even easier standing in the bath.

BUFF

Ectophile said:

Risteard said:

Ectophile said:

The lamps in my bathroom are a mixture of 12V MR16 and MR11.  The consumer unit in the house isn't particularly new, so the lights are not on an RCD-protected circuit.  One of the bathroom lights is directly above the bath.

I feel safer knowing that the lights are all SELV 12V, rather than mains.

The two transformers were already in the house when I bought it 12 years ago, and are still working now.  I have changed 2/3 of the lamps from halogen to LED, so the load on the transformers should be well below their rating.

Not sure why you would feel safer, as nearly 20 times the current will be running through the cables on the secondary side of the SELV safety isolating transformer. LED should be run from the mains - you are only creating another potential point of failure and making it less energy efficient.

It's not like you can readily reach the luminaires from the ground.

I'm not bothered about the current, it's not that high.  It's the voltage that electrocutes you.

but it's the current that kills you ...

grumbler

You don't need  big current to get killed. Typically it's heart failure, not burning like in Hollywood films. And I don't think that 12V voltage can kill in real life.

casper_gutman

BUFF said:

Ectophile said:

Risteard said:

Ectophile said:

The lamps in my bathroom are a mixture of 12V MR16 and MR11.  The consumer unit in the house isn't particularly new, so the lights are not on an RCD-protected circuit.  One of the bathroom lights is directly above the bath.

I feel safer knowing that the lights are all SELV 12V, rather than mains.

The two transformers were already in the house when I bought it 12 years ago, and are still working now.  I have changed 2/3 of the lamps from halogen to LED, so the load on the transformers should be well below their rating.

Not sure why you would feel safer, as nearly 20 times the current will be running through the cables on the secondary side of the SELV safety isolating transformer. LED should be run from the mains - you are only creating another potential point of failure and making it less energy efficient.

It's not like you can readily reach the luminaires from the ground.

I'm not bothered about the current, it's not that high.  It's the voltage that electrocutes you.

but it's the current that kills you ...

It's the current that kills you, but it has to flow through you to do so. Guess what one of the conditions is that's needed for a big current to flow through you? That's right: a high (enough) voltage!

Risteard

Ectophile said:

Risteard said:

Ectophile said:

The lamps in my bathroom are a mixture of 12V MR16 and MR11.  The consumer unit in the house isn't particularly new, so the lights are not on an RCD-protected circuit.  One of the bathroom lights is directly above the bath.

I feel safer knowing that the lights are all SELV 12V, rather than mains.

The two transformers were already in the house when I bought it 12 years ago, and are still working now.  I have changed 2/3 of the lamps from halogen to LED, so the load on the transformers should be well below their rating.

Not sure why you would feel safer, as nearly 20 times the current will be running through the cables on the secondary side of the SELV safety isolating transformer. LED should be run from the mains - you are only creating another potential point of failure and making it less energy efficient.

It's not like you can readily reach the luminaires from the ground.

I'm not bothered about the current, it's not that high.  It's the voltage that electrocutes you.

And I'm only average height, but I can reach the ceiling to change the lamps while standing on the floor.  It's even easier standing in the bath.

It's the volts that jolt but the mills that kill.

But anyhow, I didn't state that electric shock was the issue. A much higher current running through the connections into the lamp means that especially with poor connections this could run much hotter. A correctly installed recessed luminaire shouldn't give rise to the risk of electric shock, so low voltage (mains voltage) is more sensible for LED downlights than extra-low voltage. At best you are simply adding more potential points of failure with the setup.