Doc # 6.02.01 Page 1 
Rev. 4 09 Jan 2003
24-01-00 
AMM
24-01-00 
Electrical Power 
AMM
% 2. 14 VDC System Description and Operation 
% Figure 1 shows the electrical system schematic diagram. 
% A. Power Supplies 
% (1) Main Battery 
% The main battery is located in the engine compartment on the firewall on the RH side. It is a % 12 V, 35 Ah sealed battery. It connects to the engine mount ground point, the hot battery bus % and the battery relay. 
% (2) Alternator 
% The alternator is located at the bottom, left rear of the engine. A flat multi-vee belt with % automatic tensioner turns the alternator. The alternator is a 12-14 VDC, 90 A machine with an % integral regulator. The output connects to the junction box bus bar. The field can be energized % directly by the alternator excitation battery if the main battery fails. 
% (3) Alternator Excitation Battery 
% The alternator excitation battery is located on the instrument panel shelf. It is a 12 V, 1.3 Ah % sealed battery. It connects directly to the alternator field connection when the ENGINE % MASTER switch is set to ON. 
% (4) Engine Control Unit (ECU) Backup Battery 
% The ECU backup battery is located under the rear passengers′ seat on the RH side. It is a % 12 V, 12 Ah sealed battery. The ECU backup battery connects directly to the ECU alternate % power relay. 
% (5) External Power Connector 
% The external power connector is located on the left side of the fuselage, near the relay junction % box. The external power connector connects to the external power relay in the relay junction % box on the firewall. 
%) The control pin connects to the relay coil through a diode to prevent reverse connection. 
%) The + pin connects to the relay main input connection. 
%) The - pin connects to ground. 
%
Doc # 6.02.01 Page 3 
Rev. 4 09 Jan 2003
24-01-00 
AMM
% B. Power Supply Control % (1) Battery Relay % The battery relay is located in the relay junction box on the firewall. The output connects 
% directly to the relay junction box bus bar. The coil + of the battery relay is tied to the battery + % connection to the relay. The ELECTRIC MASTER key switch provides the coil ground when % set to the ON or START position. 
% (2) External Power Relay 
% The external power relay is located in the relay junction box on the firewall. The output 
% connects directly to the relay junction box bus bar. 
% If 14 VDC external power is connected, the +14 VDC on the control pin energizes the relay.
% The relay connects the external power to the relay junction box bus bar. 
% (3) Bus Structure 
% All buses (except the relay junction box bus) are flat metal strips connecting rows of circuit-
% breakers. The circuit-breakers are located immediately below the instrument panel in one row. 
% (4) Relay Junction Box Bus
% The relay junction box bus is located in the relay junction box on the firewall. It is a flat metal 
% strip connecting these relays: 
%) The external power relay.
%) The battery relay. %) The glow relay. % The bus has two outputs: 
%) The ECU bus. %) The engine starter motor solenoid. 
Page 4 Doc # 6.02.01 09 Jan 2003 Rev. 4
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