Circuit breaker planning

From the v2.4 electrical system packing list and 912ULS wiring diagram

Toggle switch (high quality DC type) Single throw Single pole On / Off 

13 x Toggle Switch SPST Single Pole On/Off (12-100)

Lever Switch # 12-100 | Aircraft Spruce ®

Toggle switch (high quality DC type) Single throw Double pole On / Off 

1 x Toggle Switch DPST Double Pole On/Off (12-200)

Lever Switch # 12-200 | Aircraft Spruce ®

Circuit breakers single action (push to reset)

1 x EC-CBR-001-X-X-0 TYCO Circuit Breaker W58 Series 1A

trim

2 x EC-CBR-003-X-X-0 TYCO Circuit Breaker W58 Series 3A

fuel pump, trim,

10 x EC-CBR-005-X-X-0 TYCO Circuit Breaker W58 Series 5A

transponder, radio, autopilot, GEA/GSU, backup battery, EFIS, backup EFIS, flaps

1 x EC-CBR-010-X-X-0 TYCO Circuit Breaker W58 Series 10A

1 x EC-CBR-015-X-X-0 TYCO Circuit Breaker W58 Series 15A

lights

1 x EC-CBR-030-X-X-0 TYCO Circuit Breaker W58 Series 30A

charge from alternator/regulator

30A master switch/circuit breaker

Needed

circuit breaker for camera mounts

split light breaker into separate taxi and landing breakers

separate breaker for nav lights and tail strobe

The breaker size is matched to the AWG-dependent current of any one branch off a given breaker. Current limits are taken from Table 11-3 on page 11-15 in AC43-13-1B:

• 22AWG -5A
• 20AWG - 7.5A
• 18AWG -10A
• 16AWG - 15A
• 14AWG - 20A
• 12AWG - 30A
• 10AWG - 40A
• 8AWG - 50A
• 6AWG - 80A
• 4AWG - 100A

Table of actual M27500 shielded wiring in build

Landing Lights (L&R) 16AWG (passing through DT connector with 13A rating)

• both routed through one 15A breaker - BREAKER 1

Taxi Lights (L&R) x 16AWG (passing through DT connector with 13A rating)

• both routed through one 15A breaker - BREAKER 2

USB to right wing 18AWG

USB to rear fuselage 18 AWG

USB Overhead 18AWG

• all three routed through one 10A breaker - BREAKER 3

Pitot heat to left wing 12AWG (passing through DTP connector with 25A rating)

• 20A breaker - BREAKER 4

Trim motor 22AWG (5A limit on wire)

• 2A breaker - BREAKER 5

L&R wing nav lights 18AWG

VS Strobe 18AWG

• allrouted through one 10A breaker - BREAKER 6

From Dynon schematics

Page 3: 5A - EFIS 1

• 5A breaker - BREAKER 7

Page 4: 3A - transponder and ADS B receiver

• 3A breaker - BREAKER 8

Page 8: 5A - com panel, com radio

• 5A breaker - BREAKER 9

Page 11: 10A - autopilot servos (each supplied with 20AWG wire, which is limited to 5A so separate breakers required for each)

• 5A breaker for roll servo - BREAKER 10
• 5A breaker for pitch servo - BREAKER 11

Additional breakers

transponder

• 5A breaker - BREAKER 12

flap motor and controller

• 5A breaker - BREAKER 13

Backup EFIS

• 5A breaker - BREAKER 14

FLARM

• 5A breaker - BREAKER 15

No breaker required for backup battery, as this is charged from the EFIS

Overhead light 22AWG

• 5A breaker, shared with other accessory 22AWG circuits - BREAKER 15