On or off

[wildebus]

If habitation electrics are disabled..
Surely that would mean no fridge on 12V....The alternative being to power it by gas whilst running. I suggest this is more risky and potentially catastrophic !

The fridge would not be considered as being on Habitation Electrics. Same as in a caravan where the fridge is powered on a separate circuit.
The fridge 12V power (as opposed to its electronics where applicable) is from the Starter Battery (via towbar on Caravans) also.

There was mention of the Sargents 'small controller' turning off the electrics? The Sargent units have one low-current supply that is a permanent 12V and is designed to be used for the Fridge (electronics & light - not power) regardless of engine state. That supply is often used for a radio but really a bit small.


If you DID have a setup that disabled ALL Leisure Battery power and the fridge was an AES type auto-selecting fridge whose electronics were on a Leisure Battery supply (that scenario would be extremely easy to build without thinking), then the fridge would stop working on ANY power source, including Gas.

 

[Obanboy666]

I am not sure that it is a common feature, but it is certainly a very useful feature to be able to totally isolate the batteries. (I recommend these to anyone asking me about electrics upgrades and installations).

It is not something you would use on a regular basis though and is very much a maintenance/layup/emergency feature.


The setup where all the habitation electrics are disabled when the engine is running is certainly very common on British Manufactured Motorhomes, but is not a legal requirement and you don't tend to see this on European built Motorhomes. I would say you see it on Autosleepers, Autotrails, Swifts, Elddis, etc as they all use Systems that are fitted in Caravans as well and it makes sense to disable everything in a caravan when towing it.

My first motorhome 2013 Swift, all hab electrics were disabled when engine running. Present 2019 Pilote, if I don’t turn off the switch for the control panel / digital tablet controller then everything is on.
I asked the dealer about it as I thought there was a fault and apparently that is how they are set up. Probably me being paranoid but I always turn it off when on the move.

 

[trevskoda]

My first motorhome 2013 Swift, all hab electrics were disabled when engine running. Present 2019 Pilote, if I don’t turn off the switch for the control panel / digital tablet controller then everything is on.
I asked the dealer about it as I thought there was a fault and apparently that is how they are set up. Probably me being paranoid but I always turn it off when on the move.

How is the batteries getting a charge, and or tablets usb toys getting charged, i have isolation switches for hab bats but only there in case of electric short causing a fire, there is also a master kill for all electrics fitted from new on top of the dashboard.

 

[Obanboy666]

How is the batteries getting a charge, and or tablets usb toys getting charged, i have isolation switches for hab bats but only there in case of electric short causing a fire, there is also a master kill for all electrics fitted from new on top of the dashboard.View attachment 60821

Didn’t say the hab batteries were disconnected, they charge from alternator when on the move.
When I turn off the control panel / tablet touch display it disables the pump, lights, and auxiliary which includes the usb sockets etc.
If I need to charge anything when on the move I use the 2 usb and 1 12v socket in the Fiat front end. Rarely have to do this as have plenty of leisure batteries and solar to keep leisure batteries topped up when I charge my Tablet, laptop, ecigs etc when static.

 

[Alan Sh]

What's an "eberspacher"?

 

[TJBi]

What's an "eberspacher"?

A heater, typically diesel-fired, but they also do petrol-fired versions and now electric heaters (for use in electric vehicles).

 

[Deleted member 144]

This all baffles me, my van has a button on the control panel that turns Off all the 12 volt in the hab area, I never turn the 12 volt off however, the fridge has a permanent 12 volt feed always on for control purposes, and the fridge runs on 12 volt when engine running it is automatic 3 way selection gas mains 12 volt but has to be turned on to automatic by a button on the fridge or Off completely by another button. Fridge aside why would I turn the 12 volt off to the habitation at any time driving or not mine is left permantly on. When the engine is running two Hab batteries are being charged from alternator on demand from the batteries and the Solar panels are also operating whether driving or engine off again charging batteries on demand from them, I assume the solar regulatorr takes care of all that? So in summary I do nothing to interrupt the the 12 volt feed to the Hab area and never have and in 6 years of having this van I have never had any problems with the 12.volt system, so what am I missing here?

 

[Pudsey Bear]

Not all vans work the same way, I'm sure there will be a reason why most automatically kill most of the habs 12v.

 

[TimSands]

Fascinating thread. Having only owned french vans, I had no idea this was a thing

 

[TR5]

All habitation electric are turned off when the engine starts usually by the Seargent small controller. This apparently is a legal requirement as I understand it to stop the tv being on and distracting following drivers, a law introduced for coaches but it also covers campers. As the controls are factory fitted they operate in this way in case a tv is fitted later. The switch you are talking about is an isolator for the habitation batteries should you wish to ensure no power loss when stored or if you are working on the habitation electrics. Leave it on at all other times for battery charging via the alternator. Without seeing it that is the best conclusion I can come to.

This shutdown is allegedly due to EMC regulations. Whilst any Electrical device can be used in a vehicle while it is static, only those devices tested to conform to certain 'electrical interference' tests may be 'powered' while the vehicle is in motion.

Motorhomes, do not require their habitation electrical systems to be disabled when the engine is started as is commonly believed. It is the path taken by UK Motorhome builders to save them conformance testing each installed product.

There is no law saying Motorhomes (or coaches, or anything else) 'Must have the lights, etc, 12v deactivated once the engine starts'.

 

[Markd]

My 2004 Bessacarr like pretty well all British motorhomes turns off hab circuits on engine start.
However the hab battery charge circuit then becomes energised through a split charge relay. Realising that this circuit only use 4mm² cable to and from the battery with a run of c10m each way - I improved the charge capability by putting in a second 10mm² cable on a direct path of c4m with chassis return again with a D+ relay to switch it in.
I get a much better charge rate - obviously not as good as B2B but it only cost a few pounds

I have a couple of cigarette lighter type 12v outlets in the hab area fed off the starter battery which look a bit original (very small wires!) but they may have been added by previous owner who knows/cares? They are handy to have for rear seat passengers or to charge tablet etc on the move. Just have to remember to not leave anything significant connected when stationary.

 

[Deleted member 144]

Fascinating thread. Having only owned french vans, I had no idea this was a thing

AHHH Glorious French Vans, mine is a Chausson So Viva La France hee hee, my previous van was an Hymer and electrics worked as described in my earlier post and never turned OFF ?

 

[Minisorella]

My 12v in the hab area switches off automatically with the ignition, so I take gizmos to the front to charge whilst driving. Oh and yes, the alternator still charges the hab batteries and I’ve got an extra meaty cable for that now, with a Cyrix battery combiner thingy. There are a few relays in the back… don’t ask me what… I know nothing! One of them must be for the fridge though because it switches to 12v with the ignition key. For a long time I thought all this was normal for all vans and none of it has been a problem in the least… unless it’s already dark when I realise I haven’t wound up the electric cab window after waving hello to everyone when I arrived

 

[Lefty107]

My old girl is 1999 and also a Hobby but no switch which is handy as I can leave the TV on and watch it in the rear view mirror and also use the toilet with flush if needed on the M25 car park.

 

[El radge]

I've owned a few vans , British , Spanish and French conversions . All of them turned off habitation when engine running

 

[DTDOG]

If habitation electrics are disabled..
Surely that would mean no fridge on 12V....The alternative being to power it by gas whilst running. I suggest this is more risky and potentially catastrophic !

No. The fridge is on a separate wiring system and runs from the alternator. It will only work while the engine is running.

 

[DTDOG]

Unusual. When the engine is started on mine, the leisure side is automatically disconnected. I only found out when I moved the van with an internal light on.

You're not alone. I only found out last week after driving along and (desperately!!) needing the toilet so pulled over in a layby and nipped to the loo (yes, it was a close call thing so left the engine running!!). Tried to flush the toilet, no power!! Thinks, I'll need to look at that when I stop. Then realised it was that the power is disconnected while engine is running.

We learn new things every day.