Unfused power? - Kawasaki Vulcan 750 Forum : Kawasaki VN750 Forums
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post #1 of 3 (permalink) Old 04-24-2016, 08:12 AM Thread Starter
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Unfused power?

So I've been pouring over the wiring diagram and something has me confused: it seems that when the engine is running the main 30 amp fuse doesn't protect anything! I'm looking for someone to show me a flaw in my logic...

When the engine is off, voltage from the battery comes in on pin 1 and must travel through the main fuse before it can get to anything else.

Once the engine is running, the R/R voltage is higher than the battery, and backfeeds through the 30 amp fuse to charge the battery. It also provides direct unfused power to the fan relay and unfused power to the white wire up to the ignition switch. Crazy?

I guess only the only non-starter related circuitry not protected by the 10 amp fuses is the turn signals, so maybe it doesn't really matter?

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post #2 of 3 (permalink) Old 04-24-2016, 08:35 AM
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I'm guessing without the source voltage to the ignition switch the accy wire would be useless and shut the bike down. The redirected power would come after the switch, so if it blew it would shut the ignition down. Check to see.

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post #3 of 3 (permalink) Old 04-24-2016, 10:52 AM
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looking at the charging system, I can see what your talking about. it looks like that.. however, as far as I know, the charging system does not output enough current to blow the 30 amp fuse, even in a short circuit situation.. therefore the R/R is limiting to less than 30 amps. if the system demand is over what the R/R can provide, it will draw off the battery. there are diodes in the junction box isolating the ign switch (thru which the majority of the current used flows) from the R/R and battery.

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