1078CT Series 3/4" Diameter Steel Door with Terminals Magnetic Contacts Installation Instructions For 1078CT 1. Drill 3/4" diameter and 1 5/8" deep holes for contacts and 3/4" diameter and 1 1/2" deep holes for magnets. Hole saw arbors available from Sentrol. 2. Strip wire from security system loop, insert into terminal block and tighten. Test for continuity. 3. Lightly coat the contact and magnet with RTV mounting compound (Sentrol part number 1905) and insert into respective holes. 1078CT 1.63" 4.
