Leave on EHU or not?

phillybarbour

phillybarbour

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I have a 2019 van with twin 90ah batteries and a 120w solar panel. While on the drive at home should I leave it on EHU or just leave it to the solar.

I currently leave it on EHU most of the time but unhook once a month for around 5/6 days.

What is best for the batteries?
 
Mines in on ehu at house most of the time but just of recent with the weather so sunny it’s been unplugged and let the solar do it all ,this wed it will go back on and fridge fired up as we are at truck fest ingliston the weekend coming
It won’t have ehu at the show.
 
The solar set up will look after your batteries unless it`s in shade for quite a bit of the time i.e. from your house or trees.
 
As already stated a 120W solar panel should normally keep your batteries topped up,
if the panel is exposed to the open sky most of the day, even in the winter if only
replacing battery self discharge.
The only proviso is if you have something drawing power off, say an alarm system or
a thermostat controlled fan directly connected to the batteries and not connected with
the main off switch.
 
I never leave mine on EHU at home, the solar keeps it all topped up, too much in fact and during summer the solar is turned off (when I remember) once batts have fully charged.
 
I don’t think leaving it on hook up will do it any harm at all, the mains charger will regulate itself so it doesn’t overcharge the batteries, so should the solar controller.
Our 2018 Burstner has a 100w panel and 2x 95 ah batteries, it will keep the batteries topped up but generally, if we aren’t using the van and it’s at home, it’s plugged in, unless there is a chance of a thunderstorm, then the EHU lead gets disconnected.
 
Some good information here.

Permanent connection to EHU in storage can be bad for a Habitation battery?
 
maingate said:
Some good information here.

Permanent connection to EHU in storage can be bad for a Habitation battery?
Click to expand...

I play safe and plug our Hymer via a cheap electronic timeswitch. I charge for 6 hours three times a week. I reasoned that should be a good compromise.

Keith
 
maingate said:
Some good information here.

Permanent connection to EHU in storage can be bad for a Habitation battery?
Click to expand...

Of course that is expert proffered fact, not disputable.
But, in practise things can be a little different, as an example my own particular
case;

I've had a solar system installed for over 25 years on the same van with
a couple of upgrades ie additional panels. Apart from battery replacement
at about 7 year intervals nothing has been replaced. The batteries have
been either regular starter or leisure batteries, nothing special. The batteries
have been on permanent solar charge.

I accept that the batteries have degraded due to being on permanent solar charge,
over and above other reasons for battery degradation.
But I have allowed for this by installing batteries with a capacity 50% more than
I am ever likely to need, so I'm not aware of gradual capacity decline due to being on
constant charge, I just accept that it's all part of the general battery degradation There isn't
much of a cost increase in buying overcapacity conventional batteries eg Varta LDFs.
For the sake of a few extra £s, I just fit and forget, and that's worth a few quid.

And I'm pretty sure a quality solar regulator with a built in intelligent charging regime
is no bad thing, certainly likely to be much better than an unsophisticated crap £10 solar controller.
 
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In over 16 years of motorhoming with 3 different vans (all with solar) I have never connected them to EHU at home except for a day or so before we go away to warm the van up and cool the fridge down.
 
Tonybvi said:
In over 16 years of motorhoming with 3 different vans (all with solar) I have never connected them to EHU at home except for a day or so before we go away to warm the van up and cool the fridge down.
Click to expand...
Ditto.

But I have adjusted the float charge down to 13.5v from 13.8 as per banner batteries latest info.

Sent from my mobile using Tapatalk
 
Solar all year round ex maybe nov dec and maybe jan,and only few day here and there with numax charger built into van,do make sure the panels charge the starter battery also,either with a relay bypass switch or a proper solar regulater.
Most of the older style chargers in motorhomes are not ment to be on 24/7 as they are not smart chargers which can be left on all year round,just remember you van alt charges at 14.4 when you drive but regulates its output and batterys dont get damaged.
The right up in early post is in regards to the old school chargers,so if you have one dont leave on for more than a few hrs a week,do remember the starter batt as these in many cases dont charge it.
 

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I have taken my EHU off and also covered the solar panel as it was getting too much of a good thing with us not using it, When we are away all is on and I only use the EHU to cool the fridge down as we are preparing to go, for a day to get the temp down .
 
My practise is to ensure that I have sufficient solar explicitly to ensure that my batteries get fully charged while off-grid.
It was my number 1 objective from the outset. That's both batteries - engine & aux.

I'm fortunate that I can almost always enjoy bright sunshine, I'm finding typically that whatever I use overnight is replenished by mid-morning with the 470Ah massive victrons back to 104%

An ehu is a bonus, when available and can be used for some of the heavies like a toaster, kettle and footspa.
But personally I'd rather let the solar do the battery management.

My sister has just had solar installed in her Rapido, after having flat batteries while in unpowered yard storage.
Now she has both batteries maintained at maximum while parked up in a yard for months at a time.
Starts on the button and plenty of power for the appliances.

james
 
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MH is parked on the west gable of my house which is also shaded by a quite high house next door. EHU is available but never connected as my 90w solar panel maintains the leisure and starter batteries all the time.

Not sure of the point of covering solar panel, but there must be some logic?
 
Its all according to the electrical quality of the charging equipment.

For example some solar regulators start off with a conditioning cycle charge voltage every time they start up.
 
On the basis that the only silly question is the unasked one.... how do you turn of a solar system please?

B2
 
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