Do the M490 and M490DE have the same footprint?
Yes, but the M490(2)DE(P)(-2) must be mounted to the push side of an out swing door.
Mounting is the same.
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Schlage Commercial » System Components » Electromagnetic Locks » M400 Series » Schlage Electronics
Can I wire a KP212 directly to an M490DE?
Yes the M490DE or DEP require a dry contact closure across the RLS input to de-energizer the magnetic coil.
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Schlage Commercial » Readers » Keypad Readers » KP Series » Schlage Electronics | Schlage Commercial » System Components » Electromagnetic Locks » M400 Series » Schlage Electronics
How can I keep the M490DE door open without the alarm going off?
Use a maintained momentary contact on the release(RLS) input. A maintained contact across the release will drop power to the mag coil. Once the contact is removed a M490DE will immediately bond to arm...
Schlage Commercial » System Components » Electromagnetic Locks » M400 Series » Schlage Electronics