Installation Instructions

190-01007-A3 GTN 6XX/7XX AML STC Installation Manual
Rev. 4 Page 3-45
Date: 1/6/2012 Tail No.: N5272K
Power Sources
Item Number
Installed
Voltage
(DC Volts)
Manufacturer Model
Number
Alternator 1 13.75 Prestolite AL 12-P70
Battery 1 12 Gill G-35
Battery Capacity: 35 x 0.75 (derating factor) = 26.25 Ah x 60 min = 1575 A-min [i]
Current drawn during Cruise (amps):
43.5 (c) enter current calculated in step 13. above
Cruise consumption during recognition:
(c) 43.5 A x 5 min = ___217.5__ A-min [ii]
Emergency Landing Current (amps):
____48.1_____ (e) enter current measured in step 15. above
Emergency Landing Consumption:
(e) 48.1 A x 10 min = ___481 __ A-min [iii]
Capacity remaining for cruise: ([i] – [ii] – [iii])
1575 - 217.5 - 481 = 876.5 A-min [iv]
Emergency Cruise Current (amps):
____34.0_____ (d) enter current measured in step 14 above
Cruise Duration ([iv] / (d) ):
876.5 [iv] / ____34.0_____ (d) = ____25.8__ min [v]
Total Duration for Flight on Emergency Power (5 + [h] 25.8 + 10) = _____40.8___ min [vi]
The total flight duration on emergency power [vi] is ≥ 30 minutes.
[PASS]
Assumptions:
1. Most severe operating condition is considered to be night IFR with the pitot heat operating.
2. Motor load demands are shown for steady state operation and do not include inrush current draw.
3. Load shedding is accomplished manually by the pilot within five minutes of warning annunciation.
4. Measured loads using a calibrated Extech clamp-on DC ammeter on the battery terminal to the master relay
cable.
Figure 3-19. Example of Completed Emergency Power Operation Calculation