Troubleshooting; Freeze During Engine Start - Kanardia INDU COMBO Manual

Combo — Manual
5

Troubleshooting

5.1

Freeze During Engine Start

In certain aircraft installations instrument freezes and then reboots
itself, when some large current consumers are switched on. This is
caused by a very short voltage drop as a consequence of the con-
sumer's power demand.
A simple electronic circuit illustrated on Figure 7 may help in this
case. The circuit consist of two elements.
ˆ The diode prevents reverse flow from the capacitor. We recom-
mend Schottky Diode 1N5818G. You can also use some other
diode, which has a low voltage drop, 1 A forward current and
at least 20 V of blocking voltage.
ˆ The capacitor serves for a very short energy reserve. Use an
aluminium electrolytic capacitor with about 1000 F, at least
25 V and at least 100 C working temperature.
+12 V
GND
Figure 7: Circuit that may prevent sudden voltage drops in certain
installations.
Diode
1N5818G
Capacitor
1000 μF, 25V, 108°C
17
5. Troubleshooting
Instrument
©
Kanardia 2015-2018