Sargent EC480 fault

greeting all

On my 2017 Kingham, whilst on EHU, the active battery is randomly changing over from leisure to vehicle, so if the EHU supply were to fail and I did not notice, all the habitation consumers would be drawing from the Vehicle battery. Anyone have any ideas

i seemed to remember from how my old Bolero worked) that, when charging, the 'active battery' was the one being charged....and if both full(ish) it would swap over as it tries to keep both topped up. on ehu, the default supply battery would be the leisure battery.

however, when you are not on ehu, the 'active battery' is really the one where the supply is coming from.

you could unplug for perhaps an hour and see what happens, youll know pretty quickly which battery the supply is coming from.

good luck

One possible conclusion to the above is that the vehicle handover briefing to the OP was not very good?

Peter Brown wrote:Its obviously too much like hard work to follow a link so:

Smart Charging

The EC400\450 and 500 ranges of PSU’s incorporate a smart charge feature, which monitors both Leisure and Vehicle batteries and automatically adjusts and directs the charger power (and solar power if a solar panel is installed) to maintain the leisure and vehicle batteries at an optimal level.

The Smart Charge feature will default to the Leisure Battery and will monitor the Vehicle Battery, if the Vehicle Battery drops below 12.4V the charger will divert the charge to the Vehicle Battery for a 4 Hour period before returning to the Leisure Battery for 4 Hours. At this point the system will default back to the Leisure Battery and monitor the Vehicle Battery.

too much like hard work for who?

With vehicle battery at 13v and the leisure battery on 13.6v and the leisure battery selected as the active battery, and on EHU. The active battery is randomly changing over to the vehicle battery and as such is the battery suppling all the habitation consumers if the EHU fails. Obviously this is not an ideal situation when the heating is on in the winter. Before anyone asks, I have tested to check which battery is suppling what in various scenarios. 
Also FYI I am a marine engineer with 40 years experiance on some of the biggest power plants in the world and have 2 engineering degrees, and am of the opinion that AS standards of engineering are pitiful

Surely if the leisure battery is the selected battery and on ehu, then the reading of 13.6 is the voltage being put out by the charger.

smithy, i think that the active battery changing over during charging on ehu should occur, but as in Peters text, perhaps not as quickly as you describe...
however, i wouldnt be necessarily convinced as to which battery is the supply one until you see it in action...
as i said, an easy test is to unplug the van for a while and the supply battery should be the leisure battery, with the user inly switching over to vehicle battery manually if needed for some reason.
good luck.

Ok here we go again
On EHU
Leisure battery about 13.6v
Vehicle battery above 12.4v
Control panel advanced setting on smart
Active battery, leisure selected
Randomly the active battery changes over to vehicle, and stays on vehicle.
If the EHU supply fails, the active battery remains Vehicle and thus all habitation consumption is fed from the active battery, ie in this case the vehicle battery. I have checked that the consumption is from the active battery (vehicle) by turning on and off various consumers and observing the voltage change.
I realise that the smart charger is designed to change the active battery from leisure to vehicle if the vehicle battery drops below 12.4v, but in theses cases of random change over the voltage has been way above that so, ergo I have a fault. I was just wondering if anyone else had experienced this or had a solution. I hope that this is now clear.

Hi Peter
The van is less than 1 year old so I will be making a warranty claim with Marquis, but from bitter experience i do not hold out much hope of getting a decent resolution on the matter and as such i am gathering as much info as possible to present to them

smithy26 wrote:With vehicle battery at 13v and the leisure battery on 13.6v and the leisure battery selected as the active battery, and on EHU. The active battery is randomly changing over to the vehicle battery and as such is the battery suppling all the habitation consumers if the EHU fails. Obviously this is not an ideal situation when the heating is on in the winter.

When you say randomnly do you mean every few seconds?  or does it stay on vehicle for the 4 hours? If 4 hours it might just be doing the behaviour described in the manual?

When I first realised I could get put on Vehicle without my conciously selecting it, I too was worried but it is nothing to panic over.
If the active battery is Vehicle then when the voltage drops to 12.4V then you get a warning. You would ofcourse switch to leisure at that point.
If you dont acknowledge the warning (e.g. your not in the van) then shortly after the system switches to Leisure itself.  At this point there is plentry left in the vehicle battery to easily start the van.

I used to worry because the manual says something about allowing vehicle battery to drop to 10.9V but the manual does not seem to be 100% accurate. My van switches to leisure long before 10.9V, usually 12.3V to 12.4V (provided Type is set to Peugeot)