Garmin GNC 420AW, Installation Manual

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400W Series Installation Manual Page 4-5
190-00356-02 Rev. G
4.2 Power, Lighting, and Antennas
This section covers the power input requirements, lighting bus input, and antenna connections. See Figure
H-5 for interconnect information.
4.2.1 Power
Pin Name Connector Pin I/O
AIRCRAFT POWER 1 (MAIN) P4001 19 In
AIRCRAFT POWER 1 (MAIN) P4001 20 In
AIRCRAFT POWER 2 (MAIN) P4001 15 In
AIRCRAFT POWER 2 (MAIN) P4001 72 In
AIRCRAFT POWER (COM) P4002 11 In
AIRCRAFT POWER (COM) P4002 12 In
AIRCRAFT POWER (NAV SUPERFLAG) P4006 44 In
AIRCRAFT GROUND P4001 77 --
AIRCRAFT GROUND P4001 78 --
AIRCRAFT GROUND P4002 21 --
AIRCRAFT GROUND P4002 22 --
AIRCRAFT GROUND P4006 41 --
CAUTION
To operate the COM transceiver in a 14 volt aircraft with a GNC 420AW, GNS 430AW
or the 28 VDC upgrade units, (see Table 3-1), a 14 to 28 volt converter such as KGS
Electronics model RB-126 or UC-14-28 or equivalent must be used. The voltage
converter should include a single short circuit protection device on its output, such as a
circuit breaker. The output should be connected to the COM power input, P4002-11 and
P4002-12 for the COM transmitter. The other power input pins (P4001-19, -20, -15, -72
and P4006-44) accept 11 to 33 VDC. Refer to Figure H-5.
A power connection on P4006-44 is only required if NAV SUPERFLAG and/or G/S SUPERFLAG is
utilized.
The power inputs P4001-19 and -20 provide power for all functions of the 400W Series unit except the
COM transmitter and the NAV & G/S SUPERFLAG outputs.
4.2.2 Lighting Bus
Pin Name Connector Pin I/O
LIGHTING BUS HI P4001 39 In
LIGHTING BUS LO P4001 40 In
The 400W Series unit can be configured to track 28 VDC, 14 VDC, 5 VDC or 5 Vac lighting buses using
these inputs. Alternatively, the 400W Series unit can automatically adjust for ambient lighting conditions
based on the photocell. Refer to Section 5.3.7 for configuring lighting inputs.
4.2.3 Antennas
Pin Name Connector I/O
GPS ANTENNA P4003 In
COM ANTENNA P4004 I/O
VOR/LOC ANTENNA P4005 In
GLIDESLOPE ANTENNA P4007 In