alternator & current draw question

[JBE]

I just replaced the factory 50A alternator in my GQ Patrol (TD42) with a brand new130A alternator and it works fine so far. Auto Electrics Australia suggested this as a bolt in/plug in replacement.
I was also told, that there was no need to upgrade the wiring.
That’s the bit, I can’t get my head around.
There is a 65A fusible link between the alternator and the battery and the cable from the alternator to the battery (Nissan wiring loom) looks pretty flimsy as well. I doubt it can deal with more than 30A. Same story with the connectors in the socket on the alternator.
I run a dual battery system with a winch off the main battery and fridge, compressor and radios off the secondary battery.
An electrician (not an auto electrician) told me that I would need to upgrade my wiring.
Now, do I or don’t I need to look into upgrading the wiring between alternator and battery or not?
Any thoughts/opinions would be appreciated.

Cheers
Joachim

[its aford not a nissan]

i would definatly upgrade the wiring , you would be mad not to

[chimpboy]

i would definatly upgrade the wiring , you would be mad not to

I agree! For a few feet of wire why not. The old wire is probably all crunchy now anyway too.

[JBE]

Thanks for the input. What puzzles me is how the old cable could have handled the 50A, the alternator is supposed to generate. I had a similar cable on my compressor with a 35A fuse and it melted.

Cheers
Joachim

[howsie]

fusible link wire although it appears small is high current wire. You'd be surprised what it can handle.

There is no best upgrade option but one of the better options in my opinion is to calculate amp draw with everything on and then remove fusible link and install a circuit breaker. So for arguements sake lets say it draws 50amp with everything on. Then put in a 50amp circuit breaker.

Fusible links are there for a reason and definatly need to be replaced with another fusible link or a circuit breaker.

Alternators even though yours is a 130amp only charge as much as they need to so it could only be putting out 40amp.

Someone please correct me if i am wrong but this is my understanding after blowing the fusible links yeserday in my cruiser

[JBE]

Howsie
You are correct that current is drawn and not pushed. My winch is the highest rated single electrical item on my truck. It has a 100A fuse and I never had an issue with it.

The fusible link is common for alt, starter and regulator on the GQ diesel as far as I can see on the wiring diagram. You blow it and the engine will cut out straight away. I would NEVER go higher with any fuse or fusible link. I've done it once and fried almost the entire wiring loom.

I had a bit of a look at the spec sheet of the alternator and it is capable of putting out 33A at 900 rpm (engine), 89A at 1350rpm, 115A at 1950 rpm and 126A at 2800 rpm.

I still think, I'll have to run a 4gauge cable from the alternator to the battery with an appropriate fuse in between.

[DamTriton]

Fusible links are there to save the loom, not the items attatched to it.

You could get a heavier gauge wire from the alt to the battery with a larger fusible link or long time constant circuit breaker, and leave out the link on the old alt-battery lead

[JBE]

You could get a heavier gauge wire from the alt to the battery with a larger fusible link or long time constant circuit breaker, and leave out the link on the old alt-battery lead

That's the plan. I'm thinking of disconnecting and insulating the alternator end of the existing cable and run a heavier gauge from alt to batt. This way, I don't have to muck around with the connections into regulator, starter,...

Cheers
Joachim