GRS 77/GMU 44 Installation Manual
Page 4-3
190-00303-10
Revision
L
4.1.2 Connector J441
Figure 4-2. Pigtail Connector J441
Table 4-2. P441 Pin Assignments
Pin Pin
Name
I/O
1 SIGNAL
GROUND
--
2
RS-485 OUT B
Out
3 SIGNAL
GROUND
--
4
RS-485 OUT A
Out
5 SPARE
--
6 POWER
GROUND
--
7 SPARE
--
8 RS-232
IN
In
9
+12 VDC POWER
In
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 Pin
Name
Description I/O
P771-18 AIRCRAFT POWER 1, GRS 77
Unit Power
In
P771-20 AIRCRAFT POWER 2, GRS 77
Unit Power
In
P771-9
MAGNETOMETER POWER OUT
Provides Power to Magnetometer
Out
P771-40 MAGNETOMETER GROUND
Ground Reference to Magnetometer
--
P771-22 POWER GROUND, GRS 77
Aircraft Ground
--
P771-24 POWER GROUND, GRS 77
Aircraft Ground
--
P441-9
+12 VDC POWER, GMU 44
Unit Power from GRS 77
In
P441-6
POWER GROUND, GMU 44
Ground Reference from GRS 77
--
