100W LED equivalent?

[CB]

I was interested to note on that motorway maintenance program on TV a couple a months ago (mainly about the highways agency around the M1/M6/M5 area) that they all talked in km.

[Andy Burns]

On the marker signs (e.g. "M1 B 176.3" rather than the ground level marker posts) the 176.3 relates to kilometers from the start of the motorway (presumably the London end is zero for the major ones)

[Dave Plowman (News)]

Not in this case. It's switched from the wall - no switch on the fitting.

[JTM]

The ground level marker posts are 100 m apart. Although not marked or indicated in any way, all (I believe) the main roads are measured and recorded in metric.

So an accident would be recorded as eg A678(road ref),

2643.75 (metric ref) 2 m north of junction with Church Street

John

[ChrisK]

These are OK too

Chris K

[Johny B Good]

That sounds fairly typical of 240v filament lamps. Much against my better judgement I allowed the XYL to specify downlighting when we had the downstairs shower/toilet refurbished just over 4 1/2 years ago. However, I was at least allowed to specify 12v lamps (this was a technicality that didn't impinge on the, imho, rather dubious, aesthetics).

I was surprised when the electrician used a 12v smpsu (60W maximum) type "Transformer" for each of the four individual 35W halogen lamps instead of, as I was expecting in my naivety, a common single 50Hz transformer to supply all four lamp fittings.

The thing is, I've not yet had to replace a single lamp in the past 4

1/2 years or so since they were installed. This rather demonstrates the value of using 12v halogen lamps over their much more fragile 240v filamented cousins which well and truly vindicated my decision to go for the 12 volt option at the time.

Quite apart from the fact that 12v filaments are both more efficient and robust than the 240v versions, it's easy enough to demonstrate the additional benefit of using current limited smpsu 12v 'transformers' by observing the definite, if brief, run up to full brightness (about quarter to half a second delay) on switch on, indicating the loss of the 10 to 12 fold turn on surge experienced by 240v halogen lamp filaments connected directly to the 240v mains supply.

These days, of course, there isn't really the need to invest in relatively costly 12v electronic 'transformers' on new lighting jobs when each such 35W lamp can so easily be replaced by a modern 220 to

240 volt 5W LED lamp of even greater output with (claimed) lifetimes of from 30 to 50 thousand hours run time.

[Dave Plowman (News)]

I've got both mains and 12v downlighters here. The mains ones - with decent quality bulbs (from TLC) seem to be lasting well. The originals which came with the fittings didn't last well.

The bathroom has the mains ones, so gets a fair bit of use. The LV ones are in the hallway.

I also have golf ball lamps round the mirror in the bathroom. Separately switched so only used for shaving, etc. Now they do have a short life. But look good. ;-)