Maintenance Manual STEMME S10-VT
Date of Issue: Jan. 01, 1998
Page 7-32
Amendment Nr. 14
Date: Nov. 30. 2007
A4011121_B23.doc
Doc. No. A40-11-121
7.7 Electrical System
Description:
See section 3.7 and "Maintenance Manual (Line Maintenance) for ROTAX Engine Type 914
Series” (Annex E)
7.7.1 General
Check wiring of entire electric system (observe section 5.2.4). Specially check cable routing for sufficient
supports, for chafing in the area of penetrations of cable (e. g. fire wall) and for signs of overheating. Check
condition of CB's, renew if required.
Check any electrical device and all switches for proper installation, tight fit and proper cable connections.
Check electrical switches in the cockpit for intended function. Perform this check during an engine test run,
refer to section 7.4.1.17.
Regulator Voltage:
Average:
13.75 V
Maximum:
14.2 V
The values indicated are valid for both busses (Engine-bus with internal generator and main bus with
external, belt driven generator).
7.7.2 Batteries
Check condition of main battery (housing, contacts, state of charge) and additional battery (if applicable).
Check mounting assy of main battery in forward tail cone.
Voltage drop of a charged main battery as new at approximately 15° C during starter operation: 2 V.
For maintena
nce on the batteries, please refer to the manufacturer’s instructions (Annex A).
WARNING:
During any maintenance on the electrical system should, if battery energy is not required for test
purposes, the negative connection to the battery should be disconnected. To remove the battery,
disconnect the negative cable first. To install the battery, connect the positive cable first, then
connect the negative.
The engine must never be started from the auxiliary, external electrical port (if fitted) without the
battery installed.
7.7.3 Grounding
Check condition of cables and connections and tight fit of main grounding cable battery-engine suspension
frame, grounding cable on LH engine suspension shockmount and grounding cables on fastening bolts of
linear actuators (spindles) of landing gear. Check condition of cables and connections and tight fit of
grounding cables on fuel pumps.
7.7.4 E-Box
Check condition of electric distribution box assy on rear fuselage steel frame. Check tight fit of connections,
tight fit of auxiliaries (capacitor, regulator) and CB's.
Open E-box (loosen and fold down front plate with regulator and remove cover sheet to the front) and check
cables, connections and components for damage, fastening, foreign objects and moisture.
