A stupid moment, changing my first UK lightbulb!

Oh, weird edison cap thingy.

I think you mean Bayonet Cap.  It's the most common type of American lamps which are Edison Screw fittings.   

living room lightbulb blew, it knocked out the downstairs lighting fuse. 

When you say fuse, is it actually a fuse or a circuit breaker?   A fuse is where you have to either physically insert a new fuse cartridge or rewire the carrier with fuse wire.  A circuit breaker just has a little on/off handle on the front which you flip up again to restore power.

The B-curve 6-amp circuit breakers which are the most common type of breaker for the lighting circuits on domestic installations do suffer from this problem when a lamp blows.  It might not happen every time (due, as Contrex already described, to the slightly different ways in which a lamp can finally give up the ghost), but it's a common occurrence, unfortunately.

If you have a house which still uses either cartridge fuses or the rewireable type of fuse carriers, they are much more resilient to the brief surge of current which flows when the lamp blows.

Sheesh. Last week I find out about the "half flush/full flush" toilets and now this.  I hope I'm able to function when I get there! 

I think you mean Bayonet Cap.  It's the most common type of American lamps which are Edison Screw fittings.   

When you say fuse, is it actually a fuse or a circuit breaker?   A fuse is where you have to either physically insert a new fuse cartridge or rewire the carrier with fuse wire.  A circuit breaker just has a little on/off handle on the front which you flip up again to restore power.

Ha, sorry yes, bayonet cap thingy. Ha, why did I say edison cap? (when clearly edison would be screw in) Doh!
And yes, I meant circuit breaker. Its a throwback from the days when my house (US) actually had a fuse box- we blew fuses all the time and would have to actually replace the cartridge. But when we finally upgraded to a circuit breaker, we used to just say "blew a fuse" out of habit- when in actuality we blew the circuit. So tough to change the terminology in my mind. Sorry for the confusion! 

And yes, I meant circuit breaker.

I had a feeling that's what you might have meant, as it's the 6A breakers which are prone to tripping when a filament lamp blows.  I've seen 5A cartridge fuses taken out occasionally, but it's much rarer due to the fuse characteristics.

Its a throwback from the days when my house (US) actually had a fuse box- we blew fuses all the time and would have to actually replace the cartridge.

If you ever live in a British house which still has fuses, you'll find they are rather different from the screw-in American types -- More like the cartridge fuses used in some older American panels for the "main" and "range" positions.

Sheesh. Last week I find out about the "half flush/full flush" toilets and now this.  I hope I'm able to function when I get there! 

The lamps are pretty easy!       

I've removed the shade ring from the lampholder in the second photo so that you can see the BC arrangement more clearly:

Well.....they don't *look* too intimidating!

Thanks for sharing the photo!

Well.....they don't *look* too intimidating!

Thanks for sharing the photo!

It's not that bad, really! I've changed them and survived!

If you can change the tail/stop light or front parking/turn signal lamp on your car, you should have no problem.   

OK, so we have a pic of the two types...What's the 'bayonet' type? Haven't ever heard of that one...

OK, so we have a pic of the two types...What's the 'bayonet' type? Haven't ever heard of that one...

The bayonet type is the one on the right hand side of the picture above (not the screw-in bulb) .

Ha, sorry yes, bayonet cap thingy. Ha, why did I say edison cap? (when clearly edison would be screw in) Doh!
 

Edison cap means screw-in?
I've never heard of 'edison cap'.

20+ years in the UK, though, and i *still* hate bayonet fitting bulbs! 

Ah! For some reason I had thought there were three types. I've run across the bayonet-type in high-intensity lamps, but the bulbs were tiny; I don't think I'd like them in full sized bulbs. I don't even really like edison screw type--I had one break trying to unscrew it, don't know how I didn't slice myself. (my mom told me to use half a potato to get the broken bulb out. I was dubious, but it worked like a charm.)

Are the compact fluorescent lightbulbs popular over there? That's pretty much all we use now.

Are the compact fluorescent lightbulbs popular over there? That's pretty much all we use now.

Over where? If you mean the UK, CF lamps are very popular. The old type filament bulbs are pretty much receding into history.

Are the compact fluorescent lightbulbs popular over there? That's pretty much all we use now.

Yes, and you can get them in both bayonet and screw fittings.  

It's pretty much a no-brainer. Using them is good for the planet, they cost the same as or only a little more than filament lamps, they last 10 years (it says on the pack of Philips ones I have) and cost 80% less to run.

It is cheaper for power companies to give them away than to build new generation and distribution plant. We got a packet of 4 x 11W that way.

Edison cap means screw-in?
I've never heard of 'edison cap'.

The standard screw-in American lamp base is often designated ES type, for Edison Screw.  As you might expect, the name derives from the early days of electric light when Thomas Edison was a major proponent (not forgetting that British inventor Joseph Swann has a prior claim to patenting the filament lamp!).    The standard size ES fitting is also known as a medium ES or medium Edison base, as there are other sizes. 

In Britain, the most common bayonet fitting is designated BC, for Bayonet Cap.  Some light fittings take a smaller version of the base which is commonly known as SBC, for Small Bayonet Cap (you'll also see SES - Small Edison Screw - for smaller versions of the screw-in lamp). 

As for compact fluorescents, the governments of both the U.K. and U.S. are working on "encouraging" their use by severely restricting the sales of general-purpose incandescent (standard filament) lamps in a few years.   Further "encouragement" is being directed in the form of building codes which require certain amounts of fixed lighting fixtures to be the low-energy types -- This is now in place in the U.K., and is likely to be increasingly so in the U.S. (no surprises that California is already ahead of the game in that respect).  The official British guidelines are now that where a low-energy light is required, the fitting installed must be a type which will accept only low-energy lamps, not a standard ES or BC fitting which is capable of accepting a regular filament lamp.

Compact fluoros do have their drawbacks though, and personally I'm not a fan of adopting them wholesale.  It takes more energy to manufacture them, and they do contain elements such a mercury which will require more careful recycling and disposal at the end of their useful lives.  While this isn't quite the extreme picture I've seen portrayed in some circles (after all, the fluoresecent tubes which have been used for decades in kitchens also contain mercury), it's certainly going to increase the problem when these lamps become even more widely used.

Although the claimed life is many years, I've already seen plenty failing in relatively short time periods, and many of the cheap brands ("Made in China" -- where else?) have an alarmingly high failure rate straight out of the box.  Many types also take a couple of minutes to get up to full brightness after switching on, which is annoying in some applications.