TM 10-6640-215-13 4-20.  REMOVE/INSTALL EXPLOSIVE PROOF DISTRIBUTION BOX A3 COMPONENTS. This task covers: a. Disassembly c.   Installation b. Removal d.   Assembly INITIAL SET-UP: Tools Required General Mechanics Tool Kit, (Appendix B, Section III, Item 2) Materials/Parts Required Lockwashers, (Appendix F) General Safety Instructions WARNING ELECTRICAL SHOCK Before   performing   any   maintenance   actions   on   electrical   equipment,   ensure   all electrical power has been turned off.  Death or serious injury may occur from failure to do this. DISASSEMBLY Disassemble Explosive Proof Distribution Box A3.  See figure 4-9. a. Open main circuit breaker A I CB I and turn generator off. NOTE Mark distribution box cover left side before removing. b. Remove six screws from outside metal panel to gain access to distribution box which is located below main power panel. c. Remove  twenty  eight  mounting  screws,  and  flat  washers  attaching  cover  to  distribution  box  and  remove cover. REMOVAL. 1. Remove Timer Relay A3K 1.  See figure 4-9. Relay A3K I is a plug-in type relay and is removed by simply lifting relay from socket. NOTE The procedure for removing the remaining four control relays is identical to those outlined in the following steps. 2. Remove Control Relay.  See figure 4-9. a. Loosen terminal screws on relay, disconnect electrical leads and tag for reconnection. 4-43