Wiring direct to battery or incorrect

[chrism6784]

Yet again another question everyone. These wires are wired directly to batteries. <br /><br />talking about the white abs black wires 

1) what are they for

2) do they need constant power or can I run to my

panel on my blue seas bar

Topic

[Tony Athens]

Mercury Smart Crap– 1.0 vs 2.xx

QSB 5.9 SmartCraft ECM, Electronic Components, and Wiring Harnesses

The power studs must say commect to “always on power”

 

Get all 100% clean and greased.. Lose power here or have something less than a 100% connection,  and you will shut down or get faults

[chrism6784]

So I think I’m getting a fault code..what do you do to reset 

[Gene Fuller]

I believe the fuse is 10 amp. The wire is fairly substantial, gauge 10.

I understand it is important that the voltage on the “unswitched terminals” must not drop below about 12 volts during starting. That is why the separate direct wiring is recommended. Any extra stuff, such as breakers, will add to the voltage drop. I believe that is also why the recommended battery size seems larger than one might expect.

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chrism6784

[chrism6784]

Out of curiosity do you know size fuse you are using, I’m running new wires today and adding an in line fuse bc mine doesn’t have one 

[Gene Fuller]

Cummins calls these the “Unswitched power terminals”.

You can guess from the name that they prefer that the wires are “unswitched”. At the very least it is mandatory that the power is not disconnected for a couple of minutes after shutting down the engine. Otherwise it is possible to get fault codes.

I have mine directly wired to the start battery, with only a fuse in-line at the battery.

 

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chrism6784

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