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Electromagnets are not at all strong in this orientation of attack. Therefore, as the drawingshows, Securitron's Z bracket should be used with an interference piece which blocks the shearing effect while the strength of the magnet blocks one arm moving while the other is stationary. For this technique to work, the motorized operator must be coordinated which means that one arm must move first to clear the interference piece before the other arm starts moving. Gate operators can normally accomplish this. The final drawing on Figure 13 shows a special mounting technique for sliding gates. We recommend the use of the "GF" type magnet and two 3" angle brackets (available from Securitron) for a neat installation. A special strike mounting technique is shown in the drawing which improves reliability. The problem is that if the strike is mounted normally to the angle bracket and the gate is a powerful one which slams shut, the magnet may be impacted to the point where its mounting screws loosen or the bracket bends. The strike mounting techniquethat is shown creates a "shock absorber" effect by the use of lock nuts at the rear of the strike and the rear of the bracket together with a spring. A through hole (rather than tapped) is drilled in the angle bracket mounting the strike and extra long roll pins are used. When the gatecloses, the strike moves in against the spring which is the shock absorbing action. 2.7 USE OF DRESS COVERS Once the physical installation is complete, you may want to consider the use of a dress cover. Dress covers are metal stampings which slip over the magnet body and are affixed with permanent double stick tape (supplied). The dress cover accomplishes three functions: First, it makes for a more attractive installation by concealing the strike plate and mounting holes. All that is seen is an attractive rectangular form on the door. Second, the cover provides an extra degree of tamper proofing and finally it allows easy alteration of the finish for architectural Rev. A.5, 8/03 Page- 14 compatibility. Dress covers are available in clear aluminum, satin black aluminum, polished stainless and polished brass finishes. Double dress covers are also available for installations on double doors. In this case, the cover fits over two locks so long as they are not separated by more than 2" (50mm). Double dress covers have all the advantages mentioned above and in addition produce the appearance of a single device which inside is really two. Consult the catalog for dress cover part numbers. 2.8 TAMPER PROOFING THE MAGNALOCK In situations where vandalism is expected, the Magnalock should be protected from tampering. The magnet itself is inherently tamper-proof being totally sealed. The magnet mounting screws are vulnerable in that the magnet can be dismounted if the screws are loosened. The allen holes on the screws can be filled with a potting compound, such as Devcon, or silicone. Alternately, the entire hole in the magnet where the screw heads fit could be filled. Butyratecaps are supplied to close the mounting holes. These provide some tamper proofing as they can't be removed by hand, but can be pried out with a tool. Regarding the strike plate mounting screw, it is covered by the strike when the magnet is energized. If tampering is anticipatedwhen the door is open, the screw socket head may be filled. Another possibility is that Securitron inventories special tamper proof screws for both magnet and strike mounting. These screws are identical allen head types except that it requires a special key to install and remove the screws. It is unlikely that a vandal would have access tothis type of key. Securitron optionally supplies the tamper proof screw sets with keys both in the form of a manual allen wrench and in a bit key usable with a drill. 3. ELECTRICAL INSTALLATION 3.1 GENERAL ELECTRICAL CHARACTERISTICS The Magnalock constitutes a low current electric load. Owing to internal circuitry, theMagnalock does not show the normal characteristics of an electromagnetic or other inductive load. Inductive kickback is suppressed, so arcing across switch contacts need not be a concern. This suppression also protects nearby access control or computer equipment from possible interference. The circuitry performs the additional functions of canceling residual magnetism ("stickiness" on release) and accelerating field collapse so that the Magnalock releases nearly instantly when power is removed. Electrically speaking, the load is nearly pure resistive in nature although there is a modest capacitive component which depends on the series. The following chart shows the current draw for each version and the degree of internal capacitance. 32 @ 12V 32 @ 24V 34 @ 12V 34 @ 24V 62 @ 12V 62 @ 24V 82 @ 12V 82 @ 24V CURRENT 300 mA 150 mA 350 mA 175 mA 250 mA 125 mA 350 mA 175 mA CAPACITANCE 0 0 0 0 30 Mfd 15 Mfd 30 Mfd 15 Mfd Capacitance can be an issue if very sensitive switch contacts are used to control the Magnalock (suc...

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