How much extra lighting can a B7300 alternator handle?

[BlackDogBrewing]

I'm looking to add additional LED lighting to my B7300, it currently has the stock alternator and lighting. Since the tractor is currently down at my mom's, I was doing some work for her, I don't have it here to look at. I've seen 40-amp conversion alternator kits, but I'm wondering what I can add with the stock alternator. Thanks.

 

[Dave M7040]

First you have a dynamo not an alternator if my brief research is correct.
Are there two wires coming off the dynamo? If the answer is yes then I am correct.
The dynamo uses a permanent magnet rather than an electrical coil to create a magnetic field which produces the electricity.
It is a big version of the old style bicycle generator which rubbed on the front tire

The question you have asked neglects to indicate how long at any one time you will be using the additional lighting.
The battery's reserve capacity will carry a load in excess of the dynamo's output for a period of time depending on the wattage of the additional lighting.
Installing the 40 amp true alternator requires electrical knowledge and is not for everyone as the wiring system needs to be increased to handle the additional output.
There are comprehensive videos on installing the Kubota 40 amp kit, which includes the new wiring, but the one I have seen is for a 7800 tractor.

The power from the engine to drive an alternator putting out 40 amps is not insignificant on a machine with 12 pto horsepower.

Dave M7040

 

[number two]

The output of the dynamo is about 13-14 amps.

LED lighting is pretty stingy with electricity so you could surely add a few.

Many owners here have done it with great success.

Good Luck!

 

[TMGT]

I have 4 27w led lights on my b2620, same dynamo which puts out about 14.5A according to Kubota, my lights are switched in pairs (one switch does 2front, other does 2 rear).

There are a few factors that determine how many lights I can run, mainly the battery state of charge and engine rpm. I found that it'll support all 4 lights but the engine speed must be over 2300 on my tractor, and that's after the batt has had a chance to charge/ recover. Dynamos are very dependent on engine speed to achieve max ouput.

There are 40a alternator kits that should fit the B7300, I plan on doing the upgrade to mine in the near future.

Right now I try to avoid using more lights then necessary to keep the load off the dynamo as it's about maxed out with all 4 running.

 

[mike69440]

Most of the time I run only the LED's not the headilgths

 

[JWR]

There is no realistic limit for you to be concerned about, certainly not the alternator or charging device. The battery will handle any loads you have. In the unlikely event you take more out than the charging device can put in per unit time, the charging device will catch up whenever you run the engine with less electrical load. The only circumstance where one would be concerned about the charging device capacity would be when the load is unusually high and staying that way for long periods of time and/or large % of the time. I have added 3 lights to a Kubota configured much like yours, all 3 of which draw more than your LED types. No problems.

The cases where one might want the higher capacity alternator would be things like running electric motors, winches, lifts, etc. -- something drawing a lot more amperage than lights.

 

[Henro]

JWR says there is no realistic limit then goes on to explain that there is...

Personally, I would look at the current capacity of the charging device, multiply that by 12 volts to get watts, and make sure my lights as rated in watts were equal, or ideally a little less, that whatever watt total I calculated.

Then I could run day and night for whatever time I wanted without worrying about over loading my charging device.

Granted, JWR's point about the battery taking up the slack short term is valid.

Personally, I just like to shoot for long term reliability and minimal worries.

 

[TMGT]

I've been out plowing snow at night for hrs on end, last thing I need is for the battery to be low when I go to start it next when it's 8 degrees out and I need some extra glow plug time.

The 4, 27w led I have is about the max I was comfortable putting on without over taxing the system.
I can't remember the numbers but I was able to maintain a proper charging voltage with all 4 lights and flashers on, as long as the engine speed was up.

I personally don't like relying on the battery to run things like lights unless it's an ocassional use like a spot light that's off more then it's on.