North Wing S-LSA Maintenance Manual
Model: Scout 912
Version 3.2
Release date 04-16-2014
Page 68
4.5.2 Checking and Replacing Voltage Regulator
Skill level:
LSR-M, A&P
Tools:
Philips screw driver
Parts:
Ducati Regulator
Task Description:
The voltage regulator is attached to the side of the Hot Box as shown below. It can be tested
using the procedure below.
1.
Remove RED wire from terminal “C” on the Hot Box (actually 3 wires from regulator
connector all joined together) and connect an extension that will allow you to measure
the voltage while the engine is running.
2.
Secure aircraft so it will not move when engine is running slightly above idle.
3.
Start engine, warm up until it will idle smoothly at around 2000 rpm.
4.
Using a volt meter, measure the
DC voltage
between the red lead you just removed
from the Hot Box and ground (which can be the aluminum case of the Hot Box). If 12-
14 VDC is present, regulator is functioning properly.
5.
If no voltage is present, or the voltage is lower than 12 volts, it could mean a defective
regulator, wire, or alternator. To determine which is the case, continue with Step 6.
6.
Measure the
“AC” voltage
being provided by the engine. This is done by measuring
the voltage between the two yellow wires going to the regulator at terminals “A” and
“B” on the Hot Box.
Do not disconnect the yellow wires from the Hot Box.
Note!
This is AC, not DC
voltage.
7.
If the voltage on the AC input wires is greater than 15 volts (normally greater than 20),
but the voltage reading on the Red output wire is less than 12 volts, the regulator is
defective and must be replaced.
HOT BOX
Ducati Regulator
(see wiring schematic
for details of
connections)
