Yet Another Cycling Forum
General Category => The Knowledge => OT Knowledge => Topic started by: JonBuoy on 18 January, 2023, 04:17:05 pm
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I am trying to replace a push button switch in a light fitting. The original one was marked with 2[2] 250~ whereas the replacement says 2[1]A 250V~.
My question is - what is the figure in the square brackets? My Googling has failed to find an answer.
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Probably the current rating when switching an inductive load (ie. a motor).
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Thanks. After some more Googling that was the conclusion that I was coming to. I was surprised that I found it so difficult to find definitive information.
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The other possibility would be a current rating for DC, though you'd expect that to come with its own voltage range - the '~' implies AC.
(It's harder for a switch to break a circuit with DC current flowing without arcing/welding the contacts, hence DC ratings tend to be a lot lower than for AC.)
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A 230 V light fitting that takes 1 A will use 230 W*.
230 W is a lot for a light. Unless your light is more than 230 W it won't matter changing the switch for one that is only rated at 1 A.
I appreciate that the new switch is rated at 2 A for ac, so my point is probably moot.
*Power factor pedants can cringe silently.
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A 230 V light fitting that takes 1 A will use 230 W*.
230 W is a lot for a light. Unless your light is more than 230 W it won't matter changing the switch for one that is only rated at 1 A.
I appreciate that the new switch is rated at 2 A for ac, so my point is probably moot.
*Power factor pedants can cringe silently.
would that make it a pedant light fitting?
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Estate agents normally spell it "pendent", referring to what it does rather than what it is. It's a shibboleth of the trade.
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Just for really boring completeness:
It looks like the marking is governed by BS EN61058-1 and a figure in brackets after the current rating is the 'rated current for motor load'. However the brackets should be rounded and these are definitely square. A figure in square brackets is the 'peak surge current for tungsten filament lamp load' which I would expect to be larger than the rated current for a resistive load. So it looks like the markings are wrong.
I reckon I could demand my £3 back from the ebay seller - or I could just fit it and I am sure it will be absolutely fine :thumbsup:
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Just for really boring completeness:
...However the brackets should be rounded and these are definitely square...
Don't dig it here, dig it over there.
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Thanks Bernard :)
...and for even more completeness - I wired in the switch to replace the one that I was told was broken and the light still didn't work ::-) Checked the tube and it was OK. Swapped in a replacement starter and behold - there was light :thumbsup:
And the moral of the story - when someone tells you which bit is broken still do your own checks. I suppose that I should be grateful for the opportunity to read through BS EN61058-1 :-\