CHAPTER 3 REPAIR PROCEDURES3.1.1 Housing Disassembly/Opening the BalanceFigure 3-5. Discovery Balance with cover removed,and also cover of main Printed Circuit Board removed.NOTE: When replacing cover, place keyway holes over cone-shaped brassscrew heads.Keyway holeon BalancecoverFigure 3-6. Keyway hole on cover guidedover cone-shaped brass screw heads.Ohaus Corporation www.ohaus.com 3-4 Discovery Balance Service Manual