Dual Alternator install

[MichaelOverfield]

Might even consider this, and be able to power my well pump, or house if needed... the price has been dropping on inverters, and they work much better than they used to. https://smile.amazon.com/dp/B06Y5H759M/_encoding=UTF8?coliid=I34702IB0MCUWP&colid=1UAW6N83PBF83

 

[Freebore]

See this this drop in Denso alternator for the 5.9:

https://www.therobson.com/product/290-10604/

I installed one of these about 18 months ago and it works just fine. I did so because I really wanted more capability for our camper as well as doing an upgrade over the 136A Bosch. I also installed a 1/0 gauge line with a mega fuse in the power line to the battery to replace that wimpy fusable link.

As far as the grid heater, the key is to make sure the long cable from the passenger side battery to the drivers side battery has no corrosion. Any current to the grid heaters is going to depend on the supply from both batteries, if that cable is weak, then the supply to the grid heater will be also and you will see your voltage drop.

 

[MichaelOverfield]

See this this drop in Denso alternator for the 5.9:

https://www.therobson.com/product/290-10604/

I installed one of these about 18 months ago and it works just fine. I did so because I really wanted more capability for our camper as well as doing an upgrade over the 136A Bosch. I also installed a 1/0 gauge line with a mega fuse in the power line to the battery to replace that wimpy fusable link.

As far as the grid heater, the key is to make sure the long cable from the passenger side battery to the drivers side battery has no corrosion. Any current to the grid heaters is going to depend on the supply from both batteries, if that cable is weak, then the supply to the grid heater will be also and you will see your voltage drop.

That is the EXACT same alternator I got at RockAuto for about $140... It's the optional Denso 220A unit offered by OEM.. part of the police and ambulance prep package. This is also the alternator that was affected by the recall.. some had defective diodes. Also note that site says not in stock.

 

[AH64ID]

What size battery bank is in your RV?


Have you already updated the wiring on your truck for the trailer? The OEM fuse is 30A, but the most I have ever seen going into the camper batteries is 15A. I've thought about upgrading the trailer pin wiring but with my 300A battery bank I just don't drive far enough on the average trip for even 50A to get it charged while driving.

 

[MichaelOverfield]

What size battery bank is in your RV?


Have you already updated the wiring on your truck for the trailer? The OEM fuse is 30A, but the most I have ever seen going into the camper batteries is 15A. I've thought about upgrading the trailer pin wiring but with my 300A battery bank I just don't drive far enough on the average trip for even 50A to get it charged while driving.

I have 240aH ( pair of group 27, 12V deep cycle Walmart batteries). These seem to do well with the inverter. I did run RV fridge on electric all day while towing and batteries were still OK, but not fully charged. I have not yet upgraded truck to trailer, want to do the dual alternator first. Might also add a third battery on the truck with isolator solenoid for RV and inverter loads... But that will be later.

 

[AH64ID]

I have 240aH ( pair of group 27, 12V deep cycle Walmart batteries). These seem to do well with the inverter. I did run RV fridge on electric all day while towing and batteries were still OK, but not fully charged. I have not yet upgraded truck to trailer, want to do the dual alternator first. Might also add a third battery on the truck with isolator solenoid for RV and inverter loads... But that will be later.

That's why you get fault lights when you run the A/C off the inverter. In order to be able to run 3000W of inverted power you will need a battery bank MUCH larger than 2 Group 27's. My 300AH bank isn't large enough to run my 1500W inverter at 1500W continuously. A 1500W draw is 128A of DC and drops my voltage to 11.65 from 13.10 on fully charged batteries (my inverter has less than 2' of cable from my batteries).

I would want a battery bank of at least 1000Ah for a 3000/6000 inverter to be utilized anywhere near it's potential, but probably closer to 1200Ah.

With a 30A draw (about what it will takes to run a 330w AC fridge circuit) you can only get 4 hours of operation out of a fully charged 220Ah bank. If you cut that to 15A (15A draw and 15A from the truck) you can get 8 hours before the batteries are dead.

I wired my inverter so that I could run the fridge if I wanted to; however, it's only in the event I run out of propane or the propane system fails. It's a loosing battle on amps to run it off the inverter while driving (and that includes an additional 100w from solar on a good day).

 

[MichaelOverfield]

John,
Thanks for the advice, I'd certainly would consider going with more batteries, but I'm not looking to add that much additional weight to the RV side, If get this Dual Alternator set up going, I'd like to add one or two house batteries under the bed of the truck, where weight is far less a concern, that is where I'd get a bigger bank. That said, I've increased load via HW heater, baseboard heater, electric heaters, and fridge up to just under the 3000W, and the inverter holds it, but granted, I'd not be keeping it there for long. Voltage does drop to around 11 under heavy load. I separated the converter/charger and added a second 30A to the original 55A, this allows me to run the small generator to help the batteries with the inverter for short duration loads.

 

[AH64ID]

John,
Thanks for the advice, I'd certainly would consider going with more batteries, but I'm not looking to add that much additional weight to the RV side, If get this Dual Alternator set up going, I'd like to add one or two house batteries under the bed of the truck, where weight is far less a concern, that is where I'd get a bigger bank. That said, I've increased load via HW heater, baseboard heater, electric heaters, and fridge up to just under the 3000W, and the inverter holds it, but granted, I'd not be keeping it there for long. Voltage does drop to around 11 under heavy load. I separated the converter/charger and added a second 30A to the original 55A, this allows me to run the small generator to help the batteries with the inverter for short duration loads.

Your batteries won't last long with that much draw, they simply aren't designed for even 1/3 of that load. That's life of the batteries and not charge. The charge won't last long either, around 30 minutes. The low voltage will also damage any DC components, to include the inverter.

Even with 85A of additional DC power you're only looking at less than 45 minutes of constant use.

The bed of the truck wouldn't be a bad spot but you sure would need some big cables to add the capacity without too much of a voltage drop.

Even a pair of 8D batteries wouldn't add enough AH to the system to allow you to effectively use 3000W of inverted power.

Why so much electric heat? Propane works great and doesn't draw over 250A.

It seems that your desires contradict each other. I'm not sure I understand why you want to avoid using both propane and a generator. With all the money invested in electric heat you can buy a lot of propane and gasoline.

 

[MichaelOverfield]

John, I was only running loads like that to test, normally the load is less that 400 Watts (mostly fridge) and short uses of the Microwave. Actually when parked with no hook-up, I shift to propane for the fridge, so load is less than about 20 Watts) On a few short tests ran the A/C for about 10 minutes, just to see what it would do. The electric heat is use only when I'm plugged in somewhere, not on the inverter. I was using it for testing purposes. My last group 27 batteries survived for 9 and 10 year respectively, with the old junk inverter, admittedly not often under any kind of serious load. The plan is for heavy cable for the Truck to RV, that same connector being able to double use for my electric hitch mounted winch as well.

 

[AH64ID]

Gotcha, that makes more sense.

 

[MichaelOverfield]

Mechanically installed.. wiring to come later. Figured out the radiator hose, did not have to replace, nor remove it. Orange electrical tape to protect connectors.#ad

 

[MichaelOverfield]

Cleaning up the threads on the Engine for the alternator bracket.#ad

 

[MichaelOverfield]

Bracket is in.#ad

 

[MichaelOverfield]

Fan shroud for 4th gen must be about 1/2" from 3rd gen. These washers with aluminum tape fix that difference.#ad

 

[MichaelOverfield]

4th gen fan shroud mount installed.#ad

 

[MichaelOverfield]

Found a 4th gen bracket, not perhaps it's original placement, but drilled out the nut on the bracket and used an existing M6 -1 threaded hole on the alternator bracket to install this, it keeps the upper hose up and out of the way for the serpentine belt on the alternator. Used a couple of 2 inch flex couplings from the plumbing section at Lowe's to hold to bracket and protect the hose at the contact point. If I later trim the radiator side of the hose about 1/4" it will clear outright, but did not want to drain and refill since that was already done recently and quite a hassle.#ad

 

[tvantuyl]

Michael, thanks for your posting effort on this electrical upgrade. I enjoyed reading through the thread.
Ted

 

[MichaelOverfield]

Michael, thanks for your posting effort on this electrical upgrade. I enjoyed reading through the thread.
Ted

You are very welcome... I've learned much from other who have posted on other topics, least I could do to help others in a similar way. More will follow in this once I have the electrical side complete. I recently ordered 2 current meters and 300A shunts to monitor the output of each alternator, to verify the circuit is working properly. When I get the electrical side figured out, I'll post a parts list and how-to, with pictures.

 

[MichaelOverfield]

Wiring in progress. First the recommended circuit from the expert. David Swanson with ST. This is a VN7004CLH high side driver, it will take the 400hz PWM signal from the ECU to the alternator and duplicate that for the second alternator. Since I had room in my project box, (and I bought 3, they are about $4 each) I actually have 2 in here, either I'll use both together if that works, or just have an installed spare if ever needed. I'm still waiting the 15KOhm resistors for the input signal. I'll be testing this before a full install to verify it works. Here's a couple of pictures:#ad

 

[seafish]

You are very welcome... I've learned much from other who have posted on other topics, least I could do to help others in a similar way. More will follow in this once I have the electrical side complete. I recently ordered 2 current meters and 300A shunts to monitor the output of each alternator, to verify the circuit is working properly. When I get the electrical side figured out, I'll post a parts list and how-to, with pictures.

Michael, when I was researching ammeters for my truck, I decided to use a Hall effect current sensor rather then a shunt. While I have not yet completed the project (dual voltmeters and ammeters to monitor the charging system and battery use) I feel that they are much safer to install and maintain as opposed to a shunt, particularly with 300 amps going to it. Here is the one I found that I believe is up to the task. The company was also very helpful in tech support. IIRC, they are about $50 each and very easy to install. See info below--

http://www.inpowerdirect.com/docs/OM-23D.pdf