Wiring and Electrical System

Video from my YouTube Channel discussing the Wiring and Electrical System

I won't get into the specifics of the ignition system in this post, but I need to say what ignition system I am going with for the purpose of understanding what I am wiring.  Because, I previously stated that I would be using a Light Speed dual electronic ignition system.  But I changed my mind and decided I would go with a SureFly electronic ignition on the left side, with a Slick Magneto on the right side.  Then, I changed my mind again...  NOW, I am installing dual Slick Magnetos (6393 retard left, 6350 plain right).  Why?  Because Champion Aerospace offers the SureStart Ignition Booster for their dual Slick Magneto Systems.  They claim engine starts on the 2nd or 3rd blade every time, hot or cold.  I'll explain more when I post the Ignition System blog...

Ok, the Electrical and Wiring process went very well!  But I could not have done it without the help of Jason Smith at Aerotronics.  Aerotronics built my instrument panel and then shipped it to me.  After I mounted the panel and it was my job to bring all of the wires (fuel pump, lights, sensors, battery contactor, P-Leads, etc) through the firewall to panel.  This is accomplished with a 37 pin P1 Circular Connector Plug, a.k.a., the P1 Plug.  Aerotronics prewires the female end of the P1 Plug at the panel.   They map all of the pin locations and then send me the pin map for wiring the male end of the P1 Plug that I assemble.  In addition, based on my choice for a ignition system, Aerotronics also supplied me with a schematic for everything else to be brought through the firewall going to the circuit breaker panel.  It's a full diagram of the entire wiring system firewall forward.  I couldn't have done it without their help.  I read Bob Knuckles book, The Aeroelectric Connection as well as other related books and websites to help me understand the process, methods and technical aspects.

Some of the items that will be mounted to the firewall.

A partial list of electrical components installed in the engine compartment:

• Primary Alternator:  B&C 60amp BC460-H
• Primary Voltage Regulator:  B&C LR3C-14
• Standby Alternator:  B&C 20amp BC410-H
• Standby Voltage Regulator: B&C SB1B-14
• Standby Alternator Current Sensor:  B&C SBK-14
• ANL Current Limiter Base:  B&C C903-3
• 40amp Current Limiter:  B&C C904 40A
• Ammeter Shunt:  B&C S870-20
• SureStart Ignition Booster:  Champion Aerospace SS1001
• Starter:  Sky-Tec 12V
• Battery:  Odyssey PC680
• Battery Contactor:  B&C S701-1
• Starter Contactor:  B&C S702-1
• Ground Block:  B&C 24 Tab Forrest of Tabs
• Hall Current Sensor:  Grand Rapids Current Sensor

Misc.

• Insulated Terminal Kit:  B&C 1TK-1
• Terminal Insulation Boots:  B&C MS25171-2S
• Ratcheting Crimping Tool:  Meterk Tool
• Lug Crimper:  TEMCO Hammer Lug Crimper
• Various Copper Eyelets:  SELTERM UL Listed Lugs
• Shrink Tubing:  Dual Wall Adhesive Shrink Tubing
• Wire Lacing:  Breyden Lacing Tapes
• Silicon Lined Ties:  Grip Lock Ties

This is a poor picture of the P1 Plug.  The left side with the white 

wires is the female end and was prewired by Aerotronics.  I ran 

the wires to the right side and assembled the male end of the plug.  

The two plug ends mate to create the connection from the (mostly)

firewall component to the instruments and switches on the panel.

Instead of mounting the current limiter and ammeter shunt to the firewall, 

these were installed on a table behind the instrument panel on the 

cabin side of the firewall.

Leads from the current limiter and ammeter shunt to the circuit breaker panel.

Battery contactor connections.  2AWG wire

to the starter.  And 4AWG wire to the alternator.

Various connections including firewall penetrations, remote oil and 

fuel sensors, battery contactor to starter contactor, etc.

Short run from the battery negative (2AWG) to the

24 tab airframe ground.  4AWG black wire from the ground 

block to the engine ground.  Ground block attaches 

to a firewall mounting tab on the airframe.   

The green donut surrounding the battery positive 

is a hall current sensor from the battery

On the left; standby voltage regulator.  On the right; SureStart Ignition Booster

EGT & CHT sensor wires above the standby voltage regulator.

I did not use any plain zip ties.  All wires were grouped together with 

polyester wire lacing.  Wire groups were secured to engine mount

tubes with Grip Lock Ties

Wire lacing can be tedious and time consuming, but I think the outcome 

is well worth the effort.  It shows pride in workmanship, and I just like the way
it looks.  Once you learn how to tie, it's actually pretty easy.  Just tie
2 half hitches as shown here, pull tight, then lock it in with a 

single square knot.

The panel was originally designed for a dual electronic ignition

system, therefore creating a need for two batteries and battery switches.

As I am now going with a dual magneto system, I eliminated one of the

switches, as seen here.  This is good.  If I every want to convert to dual

electronic ignition, my panel can accommodate. 

Eliminated the hot bus for the dual EI.  

Also installed a warning light for the standby alternator 

which comes on if the primary alternator fails.

The aftermath