Page 3-8 400W Series Installation ManualRev. G 190-00356-023.9 Equipment Mounting3.9.1 Rack InstallationUse the dimensions shown in Figure F-1 to prepare the mounting holes for the 400W Series unit. Youmay also use the 400W Series unit mounting rack itself as a template for drilling the mounting holes.1. The back plate of the rack may optionally be removed for ease of mounting in the aircraftpanel. To do so, remove the two #4-40 screws, tilt the back plate away from the tray, and thenslide the back plate to the side.2. Use the dimensions shown in Figure F-1 for the aviation rack for the various 400W Seriesunits. Install the rack in a rectangular 6.320” x 2.700” hole (or gap between units) in theinstrument panel. The lower-front lip of the rack should be flush with, or extend slightlybeyond, the finished aircraft panel.NOTEIf the front lip of the mounting rack is behind the surface of the aircraft panel, the400W Series unit connectors may not fully engage.Make sure that no screw heads or other obstructions prevent the unit from fully engagingin the rack (refer to the “Connector Engagement Test,” Section 5.2). Exercise cautionwhen installing the rack into the instrument panel. The rack is designed to facilitateremoval of the 400W Series for use in Demo Mode outside the aircraft. Deformation ofthe rack may make it difficult to install and remove the 400W Series unit.3. Install the rack in the aircraft panel using six #6-32 flat head screws and six self-locking nuts.The screws are inserted from the inside through the holes in the sides of the rack.4. If the back plate was previously removed (see Step #1), replace the back plate by positioningthe tabs on the back plate in the slots of the left side of the rack (viewing it from the cockpit)and attaching it by replacing the two #4-40 screws.3.9.2 400W Series Unit Insertion and RemovalIt may be necessary to insert the hex drive tool into the access hole and rotate the mechanism 90°counterclockwise to insure correct position prior to placing the unit in the rack. The 400W Series unit isinstalled in the rack by sliding it straight in until it stops, about 1 inch short of the final position. A 3/32-inch hex drive tool is then inserted into the access hole at the bottom of the unit face. Rotate the hex toolclockwise while pressing on the left side of the bezel until the unit is firmly seated in the rack.To remove the unit from the rack, insert the hex drive tool into the access hole on the unit face and rotatecounterclockwise until the unit is forced out about 3/8 inches and can be freely pulled from the rack.Be sure not to over tighten the unit into the rack. The application of hex drive tool torque exceeding15 in-lbs can damage the locking mechanism.3.9.3 Unit ReplacementWhenever the 400W Series unit is removed or reinstalled, verify that the unit power-up self-test sequenceis successfully completed and no failure messages are annunciated. Section 5.5.1 outlines the power-upself-test sequence.
