Fuse/Breaker in battery to started cables?

[mitiempo]

As posted it is easy to fuse a starter on a smaller engine. The trick is wire size. Many boats have 4 gauge starter and battery wiring and that causes a problem. To keep under the ampacity of the wire the fuse cannot have a very large rating.

However if the wiring is appropriately sized - say 1/0 or 2/0 - a much larger fuse can be chosen and there will not be a nuisance blow.

Fusing the starter circuit makes sense.

[FionaJC]

Thank you Watermelon123 for bringing this topic up. I have looked here in the uk and they are £5 which is about $6 so although I couldnt see the point I now feel why not?

[Dougtiff]

One possible problem nobody addressed is a LOCKED starter motor, rare, but can happen, fusing would protect that meltdown.

[rwidman]

Originally Posted by DeepFrz

This is very bad advice.

OK, You're saying the ABYC is publishing bad advice. I think that is bad advice.

[mitiempo]

Originally Posted by rwidman

Picking a value between nuisance tripping and the point where the fuse does nothing is the trick. Remember, the resistance of the wiring and the internal resistance of the battery limit the maximum current and the battery power will be quickly depleted.

The point should be between expected load and wire ampacity. The larger the wire the wider the range to pick from.

[DeepFrz]

OK, You're saying the ABYC is publishing bad advice. I think that is bad advice.

I'm not saying that at all. The ABYC doesn't say that you should not fuse the starter cable. It is a sin of omission IMHO. Any power source that has the capability of burning down your boat should be fused, again, IMHO and the opinion of many others. We fuse 16 gauge wire which will melt at a much lower current draw than the battery can deliver. Why would we not fuse the starter cable? Why? As has been pointed out here and in experiments that Maine Sail has done fusing a starter cable can be done without the risk of nuisance blowing of the fuse. Refusing (pun intended) to fuse the starter cable is unnecessarily risking your boat and perhaps many other boats in your marina.

[rwidman]

Originally Posted by DeepFrz

I'm not saying that at all. The ABYC doesn't say that you should not fuse the starter cable. It is a sin of omission IMHO. Any power source that has the capability of burning down your boat should be fused, again, IMHO and the opinion of many others. We fuse 16 gauge wire which will melt at a much lower current draw than the battery can deliver. Why would we not fuse the starter cable? Why? As has been pointed out here and in experiments that Maine Sail has done fusing a starter cable can be done without the risk of nuisance blowing of the fuse. Refusing (pun intended) to fuse the starter cable is unnecessarily risking your boat and perhaps many other boats in your marina.

I'm not going to continue to argue this. Fuse it if it makes you feel better. ABYC (the authority) does not require it and eplains why. (how many times must I post the same thing?).

Go down to your local boat dealership. Look at the boats. Starter circuit is unfused.