5 amp fuse on lighting circuit?
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BS EN 61184 says:
5 Standard ratings
5.1 Standard rated voltage
For all lampholders only a rated voltage of 250 V is allowed.
Lampholders B15d are not intended for use in circuits with ignitors.
Lampholders B22d shall not be used in circuits with ignitors without approval from the
lampholder manufacturer.
NOTE From the theoretical point of view, the minimum creepage distance required for a holder B22d will result in
a clearance sufficient to withstand a pulse voltage of 2,5 kV.
The measures required to allow easy contact travel and lamp removal might in some
situations, however, be accompanied by unforeseen reduction of the clearance without
influence on normal operation (without ignition) where only the creepage distances are
critical.
BY22d lampholders are specially designed for use in ignitor circuits.
5.2 Standard rated currents
Standard rated currents are:
– 2 A for lampholders B15;
– 2 A for lampholders B22.
The rated current shall be not less than the standard value. Rated currents higher than 2 A
are allowed.
Compliance with the requirements of 5.1 and 5.2 is checked by inspection of the marking.
Ah. It doesn't look too much like her, even in her youth, but my first reaction was to think that you'd posted a photo of my grandmother!Probably to cater for this activity?
At least the iron is the only thing plugged into that holder. From what I recall, my grandmother may well have had a Christmas tree of 'adapters' pliugged into it
An almost philosophical point (and one which is perhaps a reflection of 'how things are' today, following all the 'advances') is that, although those practices were 'horrific and unthinkable' by today's standards, I rather doubt that they they often resulted in any 'harm', or any sort. We now live in an extremely 'protected', and largely risk-averse, society!
Kind Regards, John
Interesting. As I implied before, even if those are the 'ratings' (which presumably implies that they have to pass tested at 2A), I do doubt that there are many that could not safely handle a fair bit more than that - the 'components (like pins and terminals) 'obviously' could, the only uncertainty relating to the electrical connection between the holder and whatever was plugged in.
As I also said, when used for the intended purpose (
), anything above 2A would be moot - which perhaps is the thinking behind the minimum requirement of there Standard?Kind Regards, John
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Why did you find it hard to believe?
Well, it's been demonstrated that I was wrong 'to find it hard to believe' that it was true, but the reason I said that was explained in the rest of my sentence, which you have omitted from your quote. The sentence in full was ...
JohnW2 said:
Kind Regards, John
We always carried 2 way B22 adapters with out public address kit [which all had 2 pin 5A plugs] and commonly connected to a lamp for our power. The thoughts of non earthed microphones etc gives me the heeby geebies now. Someone deciding to turn lights off for a 'slow dance resulted in losing the music on more than one ocassion.
I remember the bathroom heaters which plugged into a B22 and a 4 position pull switch for light, 1KW heater, both, off.
I'd imagine the current limiting factor will be the spring or spring tension.
I remember the bathroom heaters which plugged into a B22 and a 4 position pull switch for light, 1KW heater, both, off.
I'd imagine the current limiting factor will be the spring or spring tension.
werll, the contact between the 'pins' of the holder and the bulb/whatever that was plugged in -0 since, as I have said, the components themselves (pins & terminals) are clearly capable of carrying a lot more than 2A.
However, I would have though that those coil springs maintaining the electrical contact would be at least as good as the springy bits of metal 'gripping' the pins in any other sort of socket (BS1363 etc.), so I'm not convinced that is, in itself, a very good 'explanation'.
Kind Regards, John
The actual contact area of a BC pin to the lamp is small. It is just the very tip of the pin. They
The contact area of a plug and socket is much higher.
The contact area of a plug and socket is much higher.
Yes, that is true (although the effective "contact area of a plug and socket" can be a lot less than one might think. I remain somewhat surprised, but its seems to be 'how it is'. Even the "contact area" between conductor and terminal of a plug or socket can also be 'small'.
Kind Regards, John
I think the railway used to use lamps aproaching that.
My goodness! Judging by how hot even a 40W or 60W incandescent bulb could get, I would have thought that 'current rating' would probably have been the least of one's concerns with an ~500W bulb!
Kind Regards, John
When i started there was T1 and T2 holders often older people would burn them out with just there 150W lamps, I think a Railway lamps a bit much for a house, you would likely bash your head on it too
