Schematics G1900 wanted, question regarding fuses

[Hugo Habicht]

Hello,

when mowing yesterday I noticed that the starter did not crank as fast as it should. The battery is not being charged. The generator has output voltage, so it must be a connection problem.

I have schematics but that is for the earlier models with the dynamo and the external regulator. Does anybody have an operator manual of the later model with the generator with built in generator and could send me a good quality picture or scan?

Or can somebody confirm that the generator is still being routed via the 20A fuse?

Kind regards,

 

[Hugo Habicht]

I replaced two faulty fuses and the battery is being charged again. So far so good.

And I found a scan of newer schematics with the internal voltage regulator in the generator. Even better.

But now I am confused, the schematics shows 4 fuses, matching my tractor. But as far as I can see the fuse number 2 (30A) and fuse number 4 (15A) are in parallel. Do I see that correctly? Is that Kubotas idea of a 45A fuse? This makes no sense

Does anybody have an operator manual with the newer version schematics and could send me a good quality scan?

 

[Hugo Habicht]

Found a remark in the operators manual. Indeed, Kubota connected two fuses in parallel. This makes no sense whatsoever. Is there nobody here that can explain what they were thinking (or not)?

 

[GreensvilleJay]

Gonna be interesting to hear why they're in parallel !

 

[Hugo Habicht]

Gonna be interesting to hear why they're in parallel !

I had asked in another forum and the consent was:

1. you don't do those kindof things
2. It was probably done as an afterthought

The original dynamo had only 150W and a 20A fuse. The newer alternator had 480W (!) and hence delivered 40A. Not sure if 40A fuses were around at the time, maybe 30A was the highest. So the fuses kept burning and 50000 tractors assembled already and a quick fix was required. Another 15A in parallel and it'll be fine. Pure speculation, of course, we will never know unless a Kubota design engineer reads here and provides the answer.

The 480W figure is from the work shop manual, the alternator looks very small to me for this amount of electrical output power. And I ask myself: why so big? Apart from charging the battery and two small headlights (with about the brightness of candles) there is nothing electrical on this machine.