The Honeywell MPS99WG is a stubby recessed contact with a 3/8” diameter. The MPS99WG is different than other Honeywell recessed door and window contacts because it comes with a flat magnet instead of a round magnet. Normally you have to drill a hole in your door or window to recess mount the magnet that comes with a Honeywell recessed contact. With the MPS99WG, if you have enough of a space between the door or window and the corresponding frame, you can simply surface mount the magnet. The magnet is 1/8” deep, so even if you don’t have enough space, you can chisel out a notch to fit the magnet in so that it is flush with the edge of the door or window. Some people find this to be easier than drilling a hole.
The MPS99WG 3/8” recessed door and window contact uses a Form A, SPST, normally closed internal reed switch with a contact rating of 300mA at 30VDC. When the protected door or window is closed, the installed magnet energizes the internal reed switch to complete the closed circuit. If you were to open the door or window, the magnet would get pulled away from the contact and the contact would switch to an open state causing a fault at your alarm control panel. If you security system was currently armed, the contact switching to an open state would cause an alarm. You can only arm your system when all zones are normal so make sure to close all doors and window that are protected by a Honeywell MPS99WG before attempting to arm your security system.
To install your Honeywell MPS99WG recessed contact and its flat magnet, you will need to run a (2) conductor alarm wire from an open zone on your alarm control panel to the door or window to be protected. Next, you will need to drill a hole in the door or window frame with a diameter of 3/8”. Feed the alarm wire through the hole and splice it to the 12” leads coming off the backside of the MPS99WG to complete the connection. Push the recessed contact into the hole until it is flush with the door or window frame. Finally, use the adhesive tape to affix the flat magnet to the door or window in such a way that when the door or window is closed, the magnet is directly across from the contact. The flat magnet is great for the bottom edge of a window so that you don’t have to drill into the window and risk damaging the window. Make sure that when your MPS99WG is installed, the contact is not further than 1.25” from the magnet when the door or window is closed.
The MPS99WG recessed door and window contact is available in (2) colors so that you can choose the color that best suits your decor. If you have a white frame, choose the white contact (MPS99WWG). If you have a brown frame, choose the brown contact (MPS99BWG).