Fit NC's to the rear and NO's to the front ( you know what these are
following the recent lectures (:-))) Wire all four in series to activate
the alarm. You can then work happily away with either or both doors open
without wearing ear plugs ( IMHO such an important alarm needs to include a
cabin siren , the u/c one if fitted) and it all comes live when both doors
are (nominally) closed.
As a bonus, if the front switches are arranged to close before the back ones
open, then you have a free self -test, as there will be a brief beep when you
throw the handle.
Radio Spares stock a very (and I mean very) small microswitch
which is fully sealed and ideal for this type of application as it has
both NO and NC connections.
Part numbers
Button 302-506
Lever 320-512
The lever version costs a little more than the button version but you can always
experiment with the lever and if you decide you don't need it you can discard it
and the switch
becomes a button version.
I intend fitting these to the door pushes as suggested and will also be using
one
as a feedback
into my Micro Encoder as the gear up warning input.
Of course if you got carried away you could always use them to detect pip pin
housing
as well
:-)
Tony
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Tony Krzyzewski tonyk@kaon.co.nz
Managing Director Ph 64 9 358 9124
Kaon Technologies Fx 64 9 358 9127
Auckland
New Zealand
Networkers visit www.kaon.co.nz
Aviators visit www.kaon.co.nz/europa/272index.html
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