New harness wiring - inital

[GregH]

Feedback please.

-Switching over to ignition button from a key switch. Let me know if the PDF link works as it wasn't for me.



electrical schematic cockpit engine gauges feb 2018.pdf

[ndutton]

Need wire lengths to comment accurately.

[Al Schober]

I still have the original turn key for ignition/starter. I've considered what to do when (not if) it goes bad. Do I need the key? What security does it buy me, as the terminals are exposed on the back of the key switch? Key at this point just seems to be a pita. Would probably go to a toggle switch for ignition and a push button to activate the starter. I'd be curious to hear other thoughts on this..

[ndutton]

After more than one keyswitch failure that's exactly what I did.

[GregH]

-cockpit gauges to engine is about 10',

-solenoid to battery has a ~10' run for the positive wire and ~5' for the ground from engine to battery.

[ndutton]

Thanks. Mechanical fuel pump?

[GregH]

Thanks. Mechanical fuel pump?

yep

non EI dist.

[ndutton]

Sorry for all the questions. One more - is the ignition hot buss close to the panel or the engine?

Assuming the ign buss is near the panel, the design looks solid, all voltage drops are less than 3%. There seems to be a wiring redundancy for the gauge lighting though, perhaps there's a reason. There is no separate switch for the lighting so why the separate feed from the ign buss?

[GregH]

Sorry for all the questions. One more - is the ignition hot buss close to the panel or the engine?

Assuming the ign buss is near the panel, the design looks solid, all voltage drops are less than 3%. There seems to be a wiring redundancy for the gauge lighting though, perhaps there's a reason. There is no separate switch for the lighting so why the separate feed from the ign buss?

Good Questions and I don't mind at all - it's why I ask you folks!

- Ign buss is within a foot of the panel.

- I did not put a light switch in the circuit design at this point as the bulbs are LEDs drawing ~0.1A each.

- I ran the lighting from the buss versus directly off the 8awg wire at the ign toggle switch because I had an empty fuse slot and decided to use that instead of an inline fuse for the smaller gauge wire; as well as to keep it as a separate circuit for any future trouble shooting. Though that really doesn't answer your question - how is that circuit redundant?

[ndutton]

Actually it does answer the question.

The redundancy is you already have an ign+ wire at the gauges, could eliminate the 18 ga. lighting circuit entirely with a 14 ga. jumper from ign post to light + on each gauge. If there are plans in the future for a gauge light switch your design better accommodates it.

[joe_db]

My boat never had a key switch to start the engine. I see no security issue, anyone already on the boat intending to steal it could jumper a key in 10 seconds. Also note you probably only need about 10 different keys to start any boat

[GregH]

Doing a little more prep wiring for the gauges and harness. Decided to go with circuit breakers instead of fuses back at the gauge location. Still have to make good labels and waiting for some wire and 8awg connectors to some in.

[GregH]

Something I did not consider when working on this project - it is the same cockpit locker as the new fuel tank. There "shouldn't" ever be vapour issues but have I screwed up and now can't put the gauges and connections in the same locker!?

[ndutton]

Your gauge pod needs to be ignition protected. To achieve the spirit of ignition protection you'll need a sealed enclosure on the back (or a sealed niche in which to mount the panel), sealed wiring ports and a sealed mounting system. It can be done but will take careful planning and execution. For a spark producing component to be certified ignition proof it must pass a test in a propane saturated chamber without igniting the atmosphere.

An alternative for you could be to use only ignition protected switches, breakers or any possible spark producing components exclusively. I think sourcing these items would be a problem, the reason I suggested the sealed enclosure. I think with a little creativity you can accomplish it. Safety first as always.

[tac]

Ignition Protected Components

As Neil implies, your start pushbutton is most likely not ignition protected, and neither are the breakers.

Blue Sea makes 4 circuit (5045), and 8 circuit fuse panels (5046) that ARE ignition protected. They use ATO/ATC fuses.

https://www.bluesea.com/products/5046/ST_Blade_Compact_Fuse_Blocks_-_8_Circuits

The other components are a problem. Our Coast Guard used to publish (paper copy) a document listing all qualified IP components, but I haven’t seen that in over 35 years. Maybe your Canadian people have such a document.