Nesis III — Installation Manual
3.1
Circuit Breaker
two female crimp terminals . . . W¨
urth Elektronik, PN 649 006 137 22,
0.75 mm
2
(about AWG 18) red and blue leads.
The terminals have finitive number of mating cycles. They belong to the 25
mating cycles quality class.
3.1
Circuit Breaker
The power input must be routed trough a circuit breaker. Nesis consumes
about 800 mA at 12V on full brightness. Various peripheral devices (Daqu,
Magu, Indu, etc.) are powered via Nesis and they add to total consumption.
A rough estimate is 250 mA per device.
So a circuit breaker rated at 1.5 to 2.5 A is needed for the systems with one
Nesis. In the case of two Nesis connected to the same circuit breaker, use 2.5
to 3.5 A rated circuit breaker instead.
It is recommended that each Nesis gets its own circuit breaker.
3.2
Aircraft Master Relay
Please make sure that aircraft master relay (in fact all relays) have a protection
diode (a flyback diode)
1
, which protects against voltage spikes. A coil in relays
without this diode may cause spikes that exceed 100 V and they propagate
on the system bus. Such spikes may cause permanent damage on Kanardia
equipment and other avionics.
3.3
Backup Battery
This backup battery solution works only on 12V systems.
Nesis may be powered via an optional external backup battery system called
UPSU. The backup system consists of electronic circuit UPSU, a simple lead
VRLA AGM battery (1.2 Ah is typically used) and a DPDT (or DPST)
switch. Figure 10 shows the schematics.
The Nesis system is switched on/off by a double pole switch. This switch
turns on/off two circuits at the same time. The first one brings system power
into UPSU and the second one brings backup battery power into UPSU. When
there is enough voltage present on the system bus, system power is used and
1
Wikipedia:
https://en.wikipedia.org/wiki/Flyback_diode
19
©
Kanardia
2018