So, like everyone else who have exhausted the “z-wave mailbox sensor” on google search and read through the multiple long smartthings community threads on this topic, I came up with the same conclusion that a pre-made z-wave solution doesn’t exist. Ok, there was that failed kickstarter that wanted an insane amount of money for a 1000ft range sensor, but that doesn’t count.
I read the countless stories on dealing with metal boxes and routing antenna wires outside the mailbox and trying to impossibly extend a z-wave network using something like the aeotec extender.
I’ll state upfront that I already owned the MAIL-1200 wireless chime and it worked beautifully. My thick locking Fortress Fort Knox mailbox is made of 1/4" thick steel and 3/16" thick steel flap doors and the wireless transmitter that comes with the Mail Chime has no problem reaching the buzzer base station in my stucco house; which, by the way, stucco houses utilize metal mesh around the outside for the stucco so signals don’t normally travel very far.
Every time the flap is opened the metal ball tilt sensor activates and the buzzer inside rings three times. There is a volume/on-off rotary dial on the receiver. After measuring the voltage across the buzzer at full loudness, I measured around 7v at it’s peak, just enough to activate the coil in the micro relay. It’s easy enough to desolder the buzzer if you don’t want the sound AND smartthings alerts. I removed mine completely and wired the relay (+/-) directly to the buzzer solder points on the circuit board. Oh one last thing, you need to solder or crimp a wire from the (S) pin on the relay board to the (+) terminal as well, since you want the incoming buzzer voltage to be the supply voltage to the relay board AND the signal that activates the relay to fire.
Once the coil gets activated, the relay switches from NC to NO, thereby closing the contact on the Window Open/Close sensor. This sends the Z-wave signal to the smartthings hub and Bam! You have a mailbox sensor.
I also own Sonos speakers around the house, so I also had Smartthings send me a text message that the “mail has arrived” and speak text over the Sonos speakers “your mail has arrived”. Since the buzzer makes 3 buzzes, I didn’t want that happening 3 times, so I set the custom monitoring alert to occur only ‘Once Per Day’ on ‘M,T,W,Th,Fri,Sat’.
The only thing I had to do was setup a new device type for the window open/close sensor because the Open and Close status were reversed. No problem, just search the forum for the “My Z-wave reversed window/door sensor”. I had the same issue with my aeotec dry contact sensor and it works beautifully. Simply reverses the state in the code.
Hope this helps anyone else who’s looking for this solution.
PARTS LIST (Amazon):
$43.95, Mail Chime MAIL-1200 Wireless Mail Alert System (Made by Hanna Products Inc.), ASIN# B00103FDDU
$5.80, Tolako 5v Relay Module for Arduino ARM PIC AVR MCU 5V Indicator Light LED 1 Channel Relay Module Works with Official Arduino Boards, ASIN# B00VRUAHLE
$39.25, Z-Wave Door and Window Sensor with Nexia, RS 100, Both White and Brown Cases Included, ASIN# B008Q5CTBE