"Smart" Alternator

[Rahvin2j3]

Hi Guys,

 

I was reading this - https://www.12voltplanet.co.uk/split-charging.html- and it said that if the vehicle has a smart alternator, VSR is not recommended. Battery-to-battery charger is the one being recommended.

 

Question: The 130AH alternator that Nissan NVs have is a "smart" alternator?

 

 

Thanks.

[radin2son]

Interesting articles, the one on batteries and smart alternator.

 

I doubt NVs have anything other than a stock, standard alternator. The real question may be whether or not all NVs have the same alternator. (NV 200 has a 150 amp alternator; larger NVs have the 130 amp. Heavy duty battery availability differs.)

 

When we were in Grand Prairie, Alberta getting an oil change, I mentioned the “starter” battery only charged the AGM batteries 85%+ according to SMB. The commercial manager suggested adding an alternator; there was room. At the time it made no sense to me, maybe still doesn’t. He may have been talking about a smart alternator to specifically charge the AGM batteries. The article seems to suggest that this is not the way to go. Standard alternator works best.

 

Also, some have said it is nonsense that the alternator does not fully charge the AGM batteries when driving or at idle. I know that MBs have a high idle option to charge or run electrical.

Edited October 18, 2018 by radin2son

[Rahvin2j3]

Ah, so the best option is to run it via the stock alternator using VSR (for bulk charging it) and use solar panels for the float stage?

[radin2son]

? Someone else will have to answer this.

 

But, to overstate the obvious. If you are driving, your engine/alternator will charge and maintain the battery charge. No need for solar.

 

When parked without solar, your AGM batteries will deplete until you charge them with the engine.

 

With solar connected to your AGM batteries, a charge will be maintained and power lights and refrigerator for an indefinite time.

 

werethecarusos.com claim their solar can do this plus run their RV ac and power laptops etc. This must be new technology. Before, you could only use your ac if you had shore power. Yet

 

Someone on this site mentioned using a trickle charger for the start battery and it also charged the AGM batteries. When our NV is parked at home, I hook it up to the house current using the 30 amp shore power cord and adapter. Charge only as needed. Only the CO monitor draws power full time but this can be disconnected by removing a fuse. Draw is minimal.

 

All of the above applies to commercially built campervans. I doubt diy builders would bother with this. Solar does what they need.

Edited October 18, 2018 by radin2son

[ducnut]

A “smart” alternator is one that can detect battery health. For instance, if the battery is slowly dying, the alternator can detect that and will trigger the battery light. If the alternator is failing, it’ll trigger a separate alternator light, because it’s not producing adequate voltage. My Silverado has a smart alternator. Even though the truck had no issues starting, the battery was failing, as indicated by the battery light.

 

If it were me, to keep things simple, I’d just do what motorhome manufactures do in their lower-end units. I’d use a Ford-style starter solenoid in a positive cable from the chassis battery to the house battery/batteries. Then, anytime the engine is running, just flip on the switch for the solenoid. This eliminates any electronic wizardy and keeps things simple to diagnose. Whenever you turn off the ignition, just turn off the switch. It’ll become habit, in time.