Thread: Smart Alternator and Towing

Send a PM to 'drivesafe' on this forum and he should be able to help you with any queries.

Originally Posted by cripesamighty

Send a PM to 'drivesafe' on this forum and he should be able to help you with any queries.

cheers

Originally Posted by shadow101202

Hi Quick question


I am looking to upgrade my Camper with a factory upgrade that includes a 5kw EcoFlow system (JB Caravans). I was warned by my auto electrician that these systems may draw too much power from my smart alternator. I drive a 2020 Land Rover Defender and I have been told that a 40 amp draw is the sweet spot, yet the Ecoflow draws 70 amps. If this is correct what does the Ecoflow do if anything to protect the smart alternator. What is your advice on this?


thanks

I'm researching DCDC charging options for an upcoming install in a D300 Defender.
My vehicle is the MHEV version which has a starter generator rather than an alternator but appears to operate like a smart alternator - I can't find any info on its capacity tho.]
Which model car/charging system do you have?
Plenty of people are fitting DCDC chargers which is what we need and I've mainly seen 25A Redarc units used - power of marketing, I guess.
Looking at the JB Caravans site their systems use the Enerdrive DC2DC charger which is 40A not 70A - they do show a 70A AC mains charger and a solar controller.
If this is the case then you'll be fine - the only DCDC charger I've seen on the market greater than 40-50A is if you check on Safiery's YT channel you'll see an MHEV Defender they have set up pulling 70A.
What ever you use, the charger won't 'protect' your alternator/generator, you have to work within its capacity or risk damage. The Enerdrive unit can be set to limit how much charge it draws.

I have the P400 MHEV. JB USED to use Enerdrive but have upgraded their entire electrical package to use the Ecoflow 5kw system as it is lighter and more efficient. This does draw 70 amps not 40. My hope is that you can set the system to only draw 40amps then I am fine. If not i have to special order a older system in the van and this has adds weight and the inverter is smaller. As this is JLR Australia they have 0 clue on the max draw the Defender will handle. I have posted a question with Alto but I hold out no hope that i will get an answer.

Hi Shadow, if you don't mind, I will reply to your PM here, so others can input anything useful to help.

I have been researching the 12v current available from a new defender for quite some time and to date have found very little useful info.

But consider this, to power a modern caravan today, you must have at least 70 to 80 amps of continuous current viable or it is a waste of time towing a van.

You need up to 30 amps for a 3 way fridge.

Up to 60 or more amps to power a 50 amp DC/DC device.

Up to 30 amps for Braking and Anti Sway systems.

And none of this covers the vans own travel lighting. Stop/Park-sidelighting/Turn Indicators/Reversing lights.

So I find the claim that 40 amps is the best you can do, a bit short of the point.


If anyone has some credible info regarding the new Defenders 12v power supply, PLEASE educate us all.

After many years of towing vans, I believe it takes very little to operate elec van brakes. No van is wired to carry those sort of brake amps.. The very first video I saw from Tekonsha said around 3A to the magnets will lock everything up.. My 2017 van has Dexter standalone/autonomous sway control and this runs off a very small battery that after two years of daily use still doesnt need recharging.. yes it works.. a couple of random "operations" ( its like a millisecond power/drive loss.. scarey!) in two years..
This is just my nut and bolt reasoning,
after two years of living in this van I have exactly 5 wires running to the van, and what have I missed out on?
Please dont say induction cooking!!!!!!!!!!

its all the other power crap that makes it complicated.

Originally Posted by jwb

Plenty of people are fitting DCDC chargers which is what we need and I've mainly seen 25A Redarc units used - power of marketing, I guess.

Check out victron and enerdrive, lightyears ahead of redarc. Also check if you really do need a DCDC charger, or simply a smart isolater in the vehicle and an inverter in the van.

Originally Posted by drivesafe

If anyone has some credible info regarding the new Defenders 12v power supply, PLEASE educate us all.

There's plenty of information relating to how it works but nothing technical or capacity that I've found.
Not like a traditional 'it's a 180A alternator'
The workshop manual I have is missing any of the charging sections.
As far as real world applications, an interesting one is on Safiery's YT channel where they show an MHEV Defender fitout and talk about their charger pulling 70A.
Likely an empirical approach to working that out.
I'm starting with a conservative approach of a Victron 30A DCDC. Afterall it will be a $120k car under warranty.
Easy to double to 60A by putting a second unit in parallel if needed.