Normally closed glass reed switches

Do you have a question? Post it now! No Registration Necessary

Translate This Thread From English to

Threaded View




Just looked at RS, Jaycar and Dick Smiths,

I'm looking for a glass reed switch that is normally closed. Can't seem to
find a supplier that has any for a decent price.

I need 50 of them and while most people dont stock them, RS wants over $4
each. Im too tight to pay that much as I can see that Electus has the
normally open variety well under a dollar. (but no normally closed ones)

Anyone have any other suppliers they care to share?



Re: Normally closed glass reed switches


Quoted text here. Click to load it
They come in the elcheapo DS alarm it so they must be available . I
sourced some a while back from direct alarm supplies at a very
reasonable price .

Re: Normally closed glass reed switches



Quoted text here. Click to load it

I think you are talking about the plastic box ones. I'm after the glass reed
insert that is inside them. Just the insert, not the casing. I don't think
DAS would have them.



Re: Normally closed glass reed switches


Quoted text here. Click to load it
  no , ring them and ask
  I'm after the glass reed
Quoted text here. Click to load it
  ring them and ask
Just the insert, not the casing.


I don't think
  I believe you
Quoted text here. Click to load it

Re: Normally closed glass reed switches



Quoted text here. Click to load it


No worries. I'll call them, thanks.



Re: Normally closed glass reed switches


It is possible to 'bias' a NO reed switch with a small magnet to make it NC,
and then use your main magnet to bias it off.

I know this works because I have done it.

Just need a supply of small magnets and position it to bias the reed switch
on.

JD


Quoted text here. Click to load it



Re: Normally closed glass reed switches



Quoted text here. Click to load it

I think you are talking about the plastic box ones. I'm after the glass reed
insert that is inside them. Just the insert, not the casing. I don't think
DAS would have them.



Re: Normally closed glass reed switches


Quoted text here. Click to load it
Well if I look at DSE page and do a search for reed switches. The top of
the list is a N/C one for $1.50 (P7856). What's the matter with you? I'm
sure they will do a better price for 50.

Kevin Martin

Re: Normally closed glass reed switches



Quoted text here. Click to load it


Thanks Kevin but the search continues. The Dick Smith reed switch is
normally closed in the presence of a magnet. To me this means that it is
normally open in its normal state (form A). Some may disagree with my
terminology.

In any case I need one that stays closed when not in the presence of a
magnetic field, and opens when a magnet is brought towards it. This is a
little harder to find but its not impossible. I purchased a Form C reed
today from RS components. At over $6 it was OK for one prototype but not
good enough for quantities of 50 plus. (they only give you a dollar off at
25 units)


So the question remains where I can get a normally closed glass reed switch
at a decent quantity price sub $1.






Re: Normally closed glass reed switches


Quoted text here. Click to load it

If worst came to worst, could your application use a transistor inverter circuit
with a normally
open switch?

Cheers,
Sam

Re: Normally closed glass reed switches



Quoted text here. Click to load it

Jaycar do too.

How about using a reed switch that's open in the absence of a field and
gluing a small ceramic magnet near the reed to close it so that an
opposing magnetic field can cancel its field and open the reed switch.

--

Bye.
   Jasen

Re: Normally closed glass reed switches



Quoted text here. Click to load it

I like your lateral thinking Jasen, it would be interesting to know if that
arrangement would make a reed switch last longer or shorter.

Mark K.



Re: Normally closed glass reed switches


Quoted text here. Click to load it

Sounds very hit and miss to me, and very unreliable.



Re: Normally closed glass reed switches


Quoted text here. Click to load it


Jaycar has them (cat# SM-1002) the 25+ rate is $1.20 AU each,


Bye.
   Jasen

Re: Normally closed glass reed switches



Quoted text here. Click to load it


Nope. They are normally open.



Re: Normally closed glass reed switches


Quoted text here. Click to load it

LA5070 8+ $4.95
LA5074 8+ $5.75
LA5075 8+ $4.75
at http://www.jaycar.com.au/productResults.asp?FORMCA%T

Quoted text here. Click to load it



Re: Normally closed glass reed switches


Quoted text here. Click to load it

SM1002 is a N/O switch.
It may be easier to find a changeover than a N/C



Re: Normally closed glass reed switches


NESS Security sell them dont know the cost

http://www.ness.com.au/switches.htm

REED SWITCH GLASS ONLY
N.C. Contacts Part No. SWI540
N.O. Contacts Part No. SWI550





Quoted text here. Click to load it



Site Timeline