High Output Alternator Upgrade - Has anyone done this? - Page 5

formerFR · 03-18-2019, 10:19 AM

agreed.... and if you could get the factories to allow an option of building your unit 'without' a generator, you'd have a lot of room and capacity for another type of power generator that you wish - whether more alternator outputs, or inverters, or batteries, etc., then you'd be on to something.
Look at Winny's website, on the 'commercial vehicle' custom side - they offer an electric version of their gas-powered RV... might be an idea, though it also comes with no furniture or appliances as you would expect on a motorhome.

aircommuter · 03-18-2019, 10:48 AM

I think my position is the same but different at the same time. I drive a pickup truck because I put a camper either on it or behind it, tow a boat, tow other various trailers so I have no need for an extra vehicle like a Tesla. The extra insurance, license, and purchase price make it totally useless to me. Besides the range with the a/c running and mountain driving wouldn’t work out anyway. Plus the local utility company has a tiered pricing system so the more one uses the higher the price for the electricity.

ghhardin · 03-18-2019, 11:26 AM

In my research I have found that there are “Smart Alternators” that do a couple of interesting things to avoid Constant Alternator Loading:
Dynamic loading based on power draw – When current is needed the alternator places greater load on the engine (more resistance in the alternator) to generator more current – this is in deference to engine load
Dynamic loading based on engine load – When the engine is not underload in downhill or flat conditions, the alternator would generate more current. This has the benefit of effectively normalizing the peak and valley loads on the engine.

Oscarvan · 03-18-2019, 01:23 PM

Not ready to tear it all out, yet. But definitely know I will end up there, in fact I think we'll all end up there.....

Oscarvan · 03-20-2019, 11:49 AM

Had a very interesting conversation with a person at this outfit:

https://www.zena.net/htdocs/alternators/alt_inf2.shtml

Bottom line was that if you want to do it right.... and there's a lot of reasons you want to do it right, it's pretty involved which translates into $$

dave-g · 03-20-2019, 12:50 PM

Quote:

Originally Posted by Oscarvan

Had a very interesting conversation with a person at this outfit:

https://www.zena.net/htdocs/alternators/alt_inf2.shtml

Bottom line was that if you want to do it right.... and there's a lot of reasons you want to do it right, it's pretty involved which translates into $$

Gave that link a quick read- Soooo much to think about to do this upgrade. You really have to want it. it would be cool.

ghhardin · 03-20-2019, 01:45 PM

I agree there is a lot to include in the calculations..

The primary thing that separates modifying our rigs when compared to autos is the commercial grade cummins engine. These vehicles are in a separate grade unto them their own. And this one of the reasons why I am first looking at Delco Remy High Output Alternators as they are in the same model family of alternators that are are already installed in our rigs..

Alternators by Model Family | Delco Remy
This one is produces 24 Volts 450 Amps - that is a whopping 10,800 Watts - converting that to 120 V (negating loss) is 90 Amps @120 V AC... That is more than my 10K Onan (42 Amps per leg X2) produces (or close to)

Larry-NC · 03-20-2019, 05:50 PM

Quote:

Originally Posted by ghhardin

I agree there is a lot to include in the calculations..

...

Alternators by Model Family | Delco Remy
This one is produces 24 Volts 450 Amps - that is a whopping 10,800 Watts - converting that to 120 V (negating loss) is 90 Amps @120 V AC... That is more than my 10K Onan (42 Amps per leg X2) produces (or close to)

What RPM is required to get 24v at 450 amps? And what is the corresponding engine RPM, accounting for pulley sizes? In other words, can you get 24v at 450 amps while you idle when dry camping, or do you need a brick on the gas pedal?

Larry

Igave · 03-20-2019, 08:27 PM

And then there is affect on resale, if that means anything. Pretty interesting stuff.

ghhardin · 03-20-2019, 09:48 PM

Pretty Impressive curve

Blackrock · 03-20-2019, 10:36 PM

I worked on a lot of high output alternators on Emergency, Fire and Snow Plow vehicles and the biggest killer in these systems is the high heat they generate. If you can get rid of the heat the alternator will live a lot longer. At an idle they are near useless.

dave-g · 03-21-2019, 05:43 AM

ok I found what I was looking for-

https://www.youtube.com/watch?v=HzlDi_Yun6c

99% of what your looking for- they say will run the ac for 6-8 hours that it can auto start the motor to charge- the ac unit is 13,500 btus.

Now if we drop the auto start - we could charge while driving- run ac while driving- and run ac while at a rest stop with out running the gen set.

ghhardin · 03-21-2019, 10:57 AM

So this is a great reference for a class B.. Breaking down the math

Power Consumption Math:

8700Watt Hours @ 30 Amp
Under full 30A load at 120V the system will only provide 2.41 hours of battery power

His example of a hair dryer at 1300W
8700Wh/1300h = 6.69 hours - he said that

AC example -He states on a hot night they AC might run 6-8 hours. So doing the reverse math
(8700Wh/120V)/6h = 12A

(8700Wh/120V)/8h = 9A
A 12 Amp AC unit is believable a 9 amp...Hmmmm

Doing the Charging Math
He states the batteries can charge in 1.5 to 2 hours (note batteries charge exponentially and then asymptotically approach full charge)... So how many Amps does the 48V alternator provide?
(8700Wh/2h)/48V = 90.6 Amps
(8700Wh/1.5h)/48V =120 Amps

I am learning lots !!! The autostart - have to figure out how to add that it to the design.. Hmmm something else to research

ghhardin · 03-21-2019, 11:54 AM

https://www.lichtsinn.com/blog/tag/w...gement-system/

dave-g · 03-22-2019, 05:20 AM

I think his a/c numbers might work- as even on a hot night, the a/c unit will cycle some.

I big help is the lithium batteries- which can discharge iI think to 90%, while lead acid is 50% before damage.

But if they can fit in in a class B - I think you could get it in a class a-

I did notice one of them had a 57 volt out put that would sure help with wire sizing. All left stock alt in place.

ghhardin · 03-22-2019, 08:12 AM

Balmar/ DC Power Solutions/ Nations Alternator upgrades and powerful Xantrex/ Magnum/ OutBack and Victron Inverter-Chargers for Marine and RV's as well as Mercedes-Benz, Dodge, Chevrolet and Nissan van conversions.

Oscarvan · 03-22-2019, 08:31 AM

Hmmmm.... tasty. They offer a few 270A models.... THAT would work with my plans....

ghhardin · 03-23-2019, 09:23 AM

I have been working with Pinnacle Solutions from http://www.getlithium.com

Modeling the solution with their GT24V 300A 8DR-CTRL400
The dimension of the Onan is:
Weight 765 lbs (347 kg) 10.0 kW
Length 41.4 in (1051 mm)
Width 24.5 in (622 mm)
Height 27 in (685 mm)
1000lbs/145 lbs = 6.89 Batteries (I included the 4 lead acid house batteries in the 1000lbs)
GT24V 300A 8DR-CTRL400 Dimension are 23" x 13" x 12.87” - Its close but I think all six would fit.

So, from a weight/dimension perspective I should be able to fit 6 batteries.
Supporting 1800AH @ 24V = 43,200 WH

- This would let me run a 15 Amp 120V (1800 Watt) AC unit constantly for 24 hours - or all three constantly for 8 hours- Kinda interesting..

Oscarvan · 03-23-2019, 10:54 AM

Yep.

I'm not quite there yet... but I DO want to run one AC while driving without the generator.

I've already upgraded the inverter to 3000W PS..... Battery would be buffer (think capacitor) only. All wiring is 3/0 Inverter fuse is 300A..... plenty.

So upping the alternator is my next step. I've ordered an ammeter to put on the alternator so I can SEE how much work the existing unit (DR 8600201 160A) is actually doing. Then I can see what I would need to make it happen.

The AC would require 120A @12VDC continuous. (Batteries would take care of the startup load)

There is a DR 8600235 200A which is a DIRECT swap for what's on there. I talked to the DR people and they say I can run it at rated capacity without limitation other than heat..... It must stay cool. So a temp sensor may be in order too.....

If the chassis itself requires 50A or less that just may be enough.

It would be important to start the day with FULL batteries, use block heat to minimize starter time, and then run for a few minutes to get the chassis battery back up to where it's taking less A. THEN bring the Air on line.

It won't be idiot proof. It will have to be done monitoring the loads on the gauges. Kinda like my B-727 engineer days 30 years ago.....lol.

ghhardin · 03-23-2019, 11:06 AM

I am not there either... still doing the math

Thanks for sharing.... When talking to people about the HO Alts - they caution me on side loading the drive shaft too much because the bearings cannot take it.. Seems like an odd concern given how the cummins should be built.. Talked with the guy from ZRD Electric Designer OEM - Your Source for 24-Hour Power, DC Generator, Alt, ... he raised that concern and he was dead against Li Batteries due to the possibility of runaway and fires..

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