2018 MB Sprinter Alternator Output Inqury - Synergy

[paulywog60]

Hey Thor Community ~ I have a 2018 Thor Synergy TT24 riding on the Mercedes Benz 3.0 Diesel chassis of course and I am wondering if anyone can tell me what the voltage output of the stock alternator for this RV is?

If you do a internet parts search, it seems it may be either 180 or 220 AMP unit but not too sure. I looked through my MB manual and no details there of course...

Thanks! paulywog60

[DavidEM]

13-14 volts. Why do you want to know?

David

[Bob Denman]

Welcome to our Family of Merry Pranksters!

[paulywog60]

DavidEM ~ Thanks for your response,

Doh! I should have asked for the amperage rating of the stock unit and not voltage output ~ my bad...

My reason for asking is I have switched my battery bank from the Flood Acid units located in the stairstep well outboard location to a DIY 280 AH Lithium-Ion unit by the inboard water tank (out of the hot, cold & weather). It will now charge via Shore Power, my Solar Set or via the Generator (or all the above).

The last step is reconnecting the alternator so we can charge when driving but, a LifePo4 battery with its high demand, charging straight off the stock alternator can fry it in no time.

I now want to add a DC to DC charger and am considering either the 20 or 40 amp options from Renogy. If the stock MB alternator puts out 220 amps, I will probably opt for the 40 amp unit or if it is anything less than that, which I assume is the case, I will keep it safe and just go with the 20 AMP unit.

I did put a multimeter on the leads in the old stepwell and am getting the customary 14.1 volts at idle so I have that info.

So back to the big question asked correctly ~ anybody out there know the output amperage of the stock MB Sprinter alternator?

Thanks for the input!

[Hooligan2]

My 2016 Siesta 24St - The VIN readout shows M46 14volt 220 amp Alternator.. Readout lists build sheet for for your vehicle..

https://mbworld.org/forums/vindecoder.php

[DavidEM]

There is no right or wrong answer. When faced with a low impedance, maybe the full 220A. When faced with a high impedance such as fully charged batteries, then low- only what is required to run the chassis electronics which probably isn’t trivial. It has a fixed voltage output and E = I * R.

David

[paulywog60]

Hooligan2 ~ A Big Thank You for the MB decoder link. That can come in very handy for every Mercedes user coming across this thread for any number of reasons in the future for sure. And yes, it seems MB places a 220 volt stock output alternator in which certainly would seem to make sense for an RV application.

David ~ I see you just responded again as well too ~ Thx...

I decided to just play it safe (and about $60 less expensive) and went with the Renogy 20 amp DC to DC charger instead of the 40 amp unit. I figure at least 4 to 6 hours of driving on most travel days anyways so it should get the job recharging the batteries with the solar helping out too.

Again ~ thanks for all the input everyone ~ maybe we've just helped someone else out too right?

And thanks as well for the warm welcome to the Thor Community of RV'ers!
Having owned 8 RV's (1 VW Campervan ~ 3 Tent Trailers ~ 3 Travel Trailers and now my TT24) over the course of 40 years, I have no doubt we will continue to have much to discuss!

paulywog60

[paulwadley]

Hooligan2

That website is great. Thanks for pointing it out. I went on it and checked my VIN. What a wealth of information. I printed it up and will add it to my files.

Paul

[Bob Denman]

I've also saved that link to MBWorld, and will tackle it later on today.
Thanks!