Northern Airborne Technology 251 - Manual (Page 17)

Model 251 Passenger Speaker Amplifier
SM251 Installation and Operation Manual
Section 2 Rev: 1.00 Issue 2 Page 2-9
ENG-FORM: 805-0120.DOT
CONFIDENTIAL AND PROPRIETARY TO NORTHERN AIRBORNE TECHNOLOGY LTD.
2.4.9 Post-Installation Checks
2.4.9.1 Voltage/Resistance Checks
Do not attach the Model 251 until the following conditions are met.
Check the following:
a) Check P40 pins <6> <7> <8> and <21> for +28 Vdc relative to ground.
b) Check P40 pins <17> <18> <19> and <20> for power ground (less than 0.5
Ω).
c) Check P40 pin <22> for chassis ground (less than 0.5
Ω).
c) Check P50 pins <33> <34> <16> <14> <13> <25> and <5>, and P60 pins <3> and <8> for
continuity to ground (less than 0.5
Ω) when the relevant switches are closed.
2.4.9.2 Power On Checks
Power up the aircraft’s systems and confirm normal operation of all functions.
Upon satisfactory completion of all performance checks, make all required log book entries, electrical
load, weight and balance amendments and other documentation as required by your local regulatory
agency before releasing the aircraft for service.