R1078 1" Diameter Steel Door Magnetic Contacts Installation Instructions 1. Drill a 1" diameter and 1 1/8" deep hole for the contact. Hole saw arbors are available from Sentrol. 2. Connect the contact leads to the security system loop and test continuity. 3. The 1840 Magnet is designed to be mounted in the top channel of a metal entry/exit door. The magnet can be rotated to accommodate either wide or narrow topchannels. 4. Clean the top channel of the door. 5.
