DIY Current Limiter

[peps1]

Hey guys

Saw this video on youtube of a Home made Current Limiter for working on Amps using just a 250w bulb, and was wondering if my little diagram below was the right way to wire for the UK? (Mains power scares the hell out of me!  )

[Dave]

Yes, you can use the same circuit in UK.

There is no reason to be afraid of mains, just make sure that the wiring is done neatly and everything is well insulated. Check your connections with a multimeter before plugging it in.

One thing I do not understand, is how the heck can one make a 9 minute video about something so trivial. Everything could be described in a minute, two tops.

[peps1]

Thanks Dave!

One thing I do not understand, is how the heck can one make a 9 minute video about something so trivial. Everything could be described in a minute, two tops.

Then you really won't like the rest of his videos 

[rr100]

I would strongly discourage anybody from using a bulb as a fuse. If you want to use a fuse, just use a fuse. Smaller and smaller chances to blow up in your face. Neither one will actually be fast enough to protect your mosfets in case you're doing the wrong thing but is better to know the risks than to just do stupid things thinking you're protected.

[Excavatoree]

I would strongly discourage anybody from using a bulb as a fuse. If you want to use a fuse, just use a fuse. Smaller and smaller chances to blow up in your face. Neither one will actually be fast enough to protect your mosfets in case you're doing the wrong thing but is better to know the risks than to just do stupid things thinking you're protected.

I thought the whole point of the series light bulb was not to have the light bulb act as a fuse, but to take advantage of the lower cold filament resistance, and higher hot filament resistance.  Yes, the effect can be  too slow to protect semiconductors, but it will protect.   If the current remains low, the bulb offers a negligible resistance.  If a fault causes the current to increase, the bulb's resistance increases, thus limiting current.

I believe some oscillators use light bulbs to exploit this effect.

[Simon]

One thing I do not understand, is how the heck can one make a 9 minute video about something so trivial. Everything could be described in a minute, two tops.

quite, I got board, I know that the practical electronics magazines i used to buy in italy often showed a 12v battery being charged via a 12V 5W bulb