Power Function - Garmin GRS 77 Installation Manual

4.1.2 Connector J441
Pin Pin Name
1 SIGNAL GROUND
2 RS-485 OUT B
3 SIGNAL GROUND
4 RS-485 OUT A
5 SPARE
6 POWER GROUND
7 SPARE
8 RS-232 IN
9 +12 VDC POWER
4.2

Power Function

Power Input requirements are listed in Table 4-3. Power Input requirements and Lighting Bus inputs are
listed in the following tables. The power-input pins accept 11-33 Vdc. AIRCRAFT POWER 2 is for
connecting to an alternate power source, such as on aircraft with two electrical buses. Refer to Figures B-
1 and B-2 in Appendix B for power connections and Section 1.4.4 for lightning level note.
Table 4-3. Aircraft Power Pin Assignments, P771 and P441
Pin
P771-18 AIRCRAFT POWER 1, GRS 77
P771-20 AIRCRAFT POWER 2, GRS 77
P771-9 MAGNETOMETER POWER OUT Provides Power to Magnetometer
P771-40 MAGNETOMETER GROUND
P771-22 POWER GROUND, GRS 77
P771-24 POWER GROUND, GRS 77
P441-9 +12 VDC POWER, GMU 44
P441-6 POWER GROUND, GMU 44
GRS 77/GMU 44 Installation Manual
190-00303-10
Figure 4-2. Pigtail Connector J441
Table 4-2. P441 Pin Assignments
Pin Name Description
Unit Power
Unit Power
Ground Reference to Magnetometer
Aircraft Ground
Aircraft Ground
Unit Power from GRS 77
Ground Reference from GRS 77
I/O
--
Out
--
Out
--
--
--
In
In
I/O
In
In
Out
--
--
--
In
--
Page 4-3
Revision L