plastimo danbouy light-reed switch - from where?

Scomber

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hi
bust the 'normally closed' macro reed switch in the light -anyone tell me which replacement one i need (part no. spec etc) -and where to get a couple from-thanks
any other tips apart from being more careful when soldering and replacing it !!
 

pvb

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You can get tiny reed switches easily from places like Maplin or RS. Some come with flyleads so you can solder clumsily!
 

William_H

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I am familiar with normal reed switches available from electronics stores or found in window security alarm switches etc. However I have never seen a normally closed reed switch. I can imagine that the light is stowed near a permanent magnet which holds the reed switch open. Light goes on when magnet is not near it.
However reed switches I have seen have 2 pieces of overlapping iron wire inside a protective tube. A tiny spring tension holds them apart. However in a magnetic field that passes along the axis of the 2 wires the field across the gap pulls them together. Simple but how could you get them to move apart in a magnetic field. Perhaps using the like poles repell principal. But I have never seen them in use or for sale. So Perhaps you just need a normally open switch or someone can as often happens set me straight on such things olewill
 

RIBW

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.....anyone tell me which replacement one i need (part no. spec etc) -and where to get a couple from-

Hi,
If Farnell have the exact item - great (you probably know they have a minimum order charge - £20 last time I used them).
Failing that, I have just used (not absolutely sure mine was a Plastimo dan but the magnetic 'horseshoe' holds the circuit open):-
------ RI-90 Reed Switch, SPDT N/O (normally open) and N/C (normally closed) -------
for the same repair. I found it on eBay [mmmiillaann@gmail.com] for £2.50 including postage. You'll note it is a changeover version so I just chopped off the unwanted leg. All now working fine.
Cheers
Bob
 
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