DC to DC chargers impact on your alternator

[TheDocAUS]

A video showing the impact of the DC to DC charger on your alternator. He looks at DJI, EcoFlow and Bluetti.

Fortunately for us, INEOS has put a capable alternator into the Grenadier. It should be able to handle DC to DC chargers as part of the mix. Anything up to 30 amps should not cause problems for owners, but you do need to be conscious about how many high draw devices on at once (especially accessories you added).

The risk is higher with big Lithium batteries (over 200Ah) that can draw big power when charging.

I never had any problems with the Nissan Patrol that also had a capable alternator, but my REDARC DC to DC charger was 20 amps, later upped to 25 amps.

I would not run my Lithium battery box (with a 25 amp charger) when towing the van, as the dual battery setup and a 30 amp charger in the van would satisfy my needs, adding in another 25 amps on top for the DC to DC charger in the battery box, with lights on, air con running and other power draws may just be too much. At the very least, I would need to do some detailed sums on whether the alternator can handle it all.

View: https://youtu.be/rs-YeXoDSVM

 

[Steve.B]

A video showing the impact of the DC to DC charger on your alternator. He looks at DJI, EcoFlow and Bluetti.

Fortunately for us, INEOS has put a capable alternator into the Grenadier. It should be able to handle DC to DC chargers as part of the mix. Anything up to 30 amps should not cause problems for owners, but you do need to be conscious about how many high draw devices on at once (especially accessories you added).

The risk is higher with big Lithium batteries (over 200Ah) that can draw big power when charging.

I never had any problems with the Nissan Patrol that also had a capable alternator, but my REDARC DC to DC charger was 20 amps, later upped to 25 amps.

I would not run my Lithium battery box (with a 25 amp charger) when towing the van, as the dual battery setup and a 30 amp charger in the van would satisfy my needs, adding in another 25 amps on top for the DC to DC charger in the battery box, with lights on, air con running and other power draws may just be too much. At the very least, I would need to do some detailed sums on whether the alternator can handle it all.

View: https://youtu.be/rs-YeXoDSVM

Ineos Grenadiers have a 250a alternator, and the rule of thumb as far as I can remember is the DC -DC charger amp rating should be less than 50% of the the alternator capacity, so a 250a alternator would hardly be stressed with a 40a DC - DC charger attached.

 

[Tazzieman]

In the 80s my brother told me ''the hardware man giveth , the software man taketh away''
Electrical accessories are now so numerous and power hungry , bigger batteries needed, more stress for a system designed in the past!
Things get expensive when things go wrong!

 

[TheDocAUS]

Ineos Grenadiers have a 250a alternator, and the rule of thumb as far as I can remember is the DC -DC charger amp rating should be less than 50% of the the alternator capacity, so a 250a alternator would hardly be stressed with a 40a DC - DC charger attached.

Thanks, I did see another post saying 250 amps, which is a decent alternator. But what is the power usage of say a Trialmaster? What is the overhead for accessories? I suppose with 250 amps there is room to move and just use common sense with the accessories being used at a given time.

Plus the car will probably tell you if the draw is too much. I think someone posted such a message last week concerning the 4000w inverter draw. I would need to check to be sure.

 

[anand]

50A DC-DC charging while simultaneously having the ARB twin air compressor (70ish amp actual draw) still allows it to maintain proper voltage at idle for me.

I've been running the 50A DC-DC charger for something around 20k miles at this point with no ill effects found.

Anecdotally, our Sprinter has a 250A alternator as well, from which we are running a trio of 30A DC-DC chargers in parallel. That set up has been in place for over 3 years at this point with the only caveat being that if it is hot (fans running) and it will be idling for >15 minutes (either stationary charging, or remote start, etc), I'll bump it into high idle mode (1200rpm)

 

[LeeroyJ]

I've been running the EcoFlow 800W Alternator Charger for a while now (~6 months), I use it exclusively to run my EcoFlow Delta 2 Max (2400W LFP Generator). It's been flawless, but I didn't know I was supposed to be worried. When running my Grenadier, the Delta 2 Max shows that it is receiving 799 W until it gets to 100%.

After a night of camping when I've run the Delta 2 Max down (I run my fridge, Starlink, and the usb ports in my tent that generally have two iPhones connected) I can tell that the Grenadier's rpms at idol are lower, but other than that I don't see / hear any difference when driving and it is great for quickly recharging the Delta 2 Max.

I would still like to use my NATO plug to connect to the Anderson plug on my offroad trailer (that has a bank of Lithium batteries) but I need to get someone who knows what they are doing to assess if the trailer and/or the Grenadier can handle that load. Maybe not at the same time the EcoFlow Alternator Charger is running.

 

[TheDocAUS]

I've been running the EcoFlow 800W Alternator Charger for a while now (~6 months), I use it exclusively to run my EcoFlow Delta 2 Max (2400W LFP Generator). It's been flawless, but I didn't know I was supposed to be worried. When running my Grenadier, the Delta 2 Max shows that it is receiving 799 W until it gets to 100%.

After a night of camping when I've run the Delta 2 Max down (I run my fridge, Starlink, and the usb ports in my tent that generally have two iPhones connected) I can tell that the Grenadier's rpms at idol are lower, but other than that I don't see / hear any difference when driving and it is great for quickly recharging the Delta 2 Max.

I would still like to use my NATO plug to connect to the Anderson plug on my offroad trailer (that has a bank of Lithium batteries) but I need to get someone who knows what they are doing to assess if the trailer and/or the Grenadier can handle that load. Maybe not at the same time the EcoFlow Alternator Charger is running.

You don't need to be worried, just be sensible in what you do and plan ahead like you are doing.

One of the videos on this topic (DC to DC chargers), was using a car with a 70 amp alternator - hardly surprising they had issues. 250 amps gives us head room and options.