Installation Instructions

GTN 6XX/7XX AML STC Installation Manual 190-01007-A3
Page 3-40 Rev. 4
CAUTION
The pitot heat should only be switched on long enough to take the current measurement
and then switched off. The pitot probe may get hot so care should be exercised to avoid
burns or damaging the unit.
11. Using the tabulation completed above, switch on all continuous electrical loads used in the
normal takeoff/landing phase and record ammeter current reading. Measurements must be taken
with the landing lights ON and OFF (measurements (b1) and (b2) in Figure 3-16).
12. The following items should be taken into consideration for this measurement:
o The autopilot circuit breaker should be closed, and the autopilot should be engaged.
13. Using the tabulation completed above, switch on all continuous electrical loads used in the
normal cruise phase and record the ammeter current reading (measurement (c) in
Figure 3-16).
o The autopilot circuit breaker should be closed, and the autopilot should be engaged.
14. Using the tabulation completed above, switch on all continuous electrical loads used in the
emergency cruise phase and record the ammeter current reading. Record the current drawn with
the Landing Light switched OFF and again with the landing light switched ON.
15. Using the tabulation completed above, switch on all continuous electrical loads that are used for
the emergency landing phase and record the ammeter current reading.
16. Using the values measured and recorded, complete the ELA using the blank form in
Figure 3-15. Verify that the maximum demand does not exceed 80% of the alternator data plate
rating.
NOTE
It is permissible to exceed 80% of the alternator data plate rating during the
takeoff/landing phase of flight when the pitot heat and landing light are switched on
simultaneously. However, for this condition (i) you must not exceed 95% of the
alternator data plate rating, and (ii) you must not exceed 80% of the alternator data plate
rating with the pitot heat on and the landing light off.