Magneto Output for the 195?

[Cabin2010]

Good Morning All.

I need someone's electrical brain to help out with a question..

What's the Amperage output of the BRP's Magneto on the 250 HP motors?

I've run a dual battery system and now have the concern it maybe to much for the charging system.

I need to install the Trolling Motor battery, from the factory there's no direct charging for that system.

I have a couple options for on board charging.

1) Install the Minn Kota DC Alternator
2) Solar backup.

With already charging dual batts I don't know if the system can handle adding the DC Alternator.

Thoughts... Specs on the Magneto?

Thanks

 

[FSH 210 Sport]

Is there any of this info in your owners manual ?

I don’t know anything about the BRP engines.. but if they’re like the Yamaha PMG permanent magnet generators then the generator is always at full output with excess current being shunted to ground.

 

[Cabin2010]

Only thing I could find is a 600 watt rating for the magneto. If you do the math at 12 volts that's under a 50 AMP output (if i'm doing my math correctly) That's not a lot of charging power.

 

[Luc Lafreniere]

550 W @ 6000 RPM

According to BRP's manual. To my knowledge, they usually output somewhere between 12 and 15V to charge the system. So 550W / 15V = ~36A.

Regardless, this post may be helpful: https://jetboaters.net/threads/scarab-add-a-battery-modification.3135/?fbclid=IwAR28nQQ0WJj4jLJ1KTIKe8xZ5DTIRPgwvTf3zSeuBQFmXm8DG-E3xGh94gs

I don't have this expertise.... so can't provide much guidance on this one.

 

[Cabin2010]

Thanks, that's pretty much what I installed, although i added an Automatic Charging Relay to the system.

I think I'm leaning toward a solar back up, adding the DC alternator would put a huge drain on the system...

 

[Luc Lafreniere]

I personally have a solar trickle charger while I'm away from my boat. Piece of mind.

 

[FSH 210 Sport]

Thanks, that's pretty much what I installed, although i added an Automatic Charging Relay to the system.

I think I'm leaning toward a solar back up, adding the DC alternator would put a huge drain on the system...

If you have the PMG generator that I mentioned above you will not be putting a strain on the charging system, it is always at full output. The rectifier turns the AC into DC voltage through the use of diodes, this DC voltage is regulated by shunting the excess voltage to ground, thus the charging system is always at full output.

Automotive style alternators vary the electromagnetic field on the rotor to regulate output. On a PMG generator the magnetic field is fixed as the rotor has permanent magnets installed in it, so the field is fixed, as is the output. One of the advantages of a PMG generator over a automotive style is that it does not need voltage for it to operate like an automotive style does. So once the engine is started it starts putting out its full potential at a given rpm.

So lets say your system is charging at 14.5 vdc, that is 41 amps of output, figure 10-15 max to run the boat as far as the engine goes. That leaves you 26 amps to either charge batteries solely, or a little less if you are running some accessories. Which is pretty darn good, not like an outboard but still darn good.

Those minnkota alternator chargers say that they require a minimum of 35 amp alternator to run. You might also look at Trollbridge chargers. I was looking at both of them to charge my trolling motor bank while off grid, with the Trollbridge being more desirable.. Now that I have the lithium batteries that may be a possibility due to their low resistance.. but my boat might have a total of 5-10 amps of charging capacity left over to charge batteries and run accessories. I think my boats stators are 200 watt, so very small compared to your boats stator.