PAL-T NO or NC with the Magnet Near

[Ranman]

I'm looking at the specs of the Honeywell PAL-T contacts and it shows these are Form A reed switches which I take to mean the contact/circuit is open when the magnet is near (door is closed/secure) and closed when the magnet moves away.. I also read on this forum that most contacts are commonly NC contact/circuit is closed when the magnet is near. This impacts whether you would place your EOL in series or in parallel.

For those who regularly install PAL-T contacts, do you wire the EOL in parallel or in series to achieve three state zone wiring?

 

[Del91574]

Incorrect.

The operation is opposite of what you describe. Form A means a single pole connection, and in the case the PAL and most other contacts, they are closed loop.

EOLR is in series.

 

[Ranman]

Thanks DEL. I thought that was the case, but somehow got confused. I now understand that the PAL contacts are still NO which is Form A "make", however NO contacts connect the circuit when the relay is activated (magnet is near/door closed & secure) and disconnected when the relay is open (magnet is far/door is open).

So this means EOLR in series as you have confirmed.

DEL, do you have any tricks on how you connect the EOLR to the 22/2 and contact and hide it in the PAL in series? I'm sure I can figure it uot, but I bet you have a nice, neat way of doing it. A pic would be great,but I'd take any feedback you'd care to provide. Thanks.

 

[Del91574]

The EOLR's will fit under the cover, you need to do some judicious cutting and arranging of the EOLR, since it's tight. The connection needs to be soldered and shrink tube, nothing else fits.

The contacts are NO, however the magnet in proximity energizes the reed, so to speak.

A relay is an entirely different item from a reed switch, and many are labelled when the relay is energized, however there are some out there that are "reversed". I've found the best way, unless I can remember after wiring a pile of them from the same manufacturer, is to meter them and verify.

Unfortunately, while I tend to buy the same 2 manufacturers, sometimes we are spec'd to connect to other units which don't maintain convention.