Charging battery on site

[DerekBrad]

Hello all,

I have just fitted a new Nordellec 143 DU to my van (now on the third one!). I am due to go off to France in about a week's time and feeling rather unconfident about the new unit, will be taking my Aldi battery charger along for the ride. If I should need to use it,should I disconnect the leads in the battery box before connecting the crocodile clips of the charger? I rather think that I should but would appreciate the real "gen" from one or more of you boffins out there! Thanks in advance.
Regards
Derek

 

[Dustydog]

Derek
What is the output , charge rate , of your Aldi charger?
If it's less than the OME there shouldn't be a problem unless it has unknown peaks / spikes.
I have charged both car and caravan without disconnecting but then my charger does turn out far less than the Bailey unit. Car wise the chargers output is way below the alternator.
If you have a non sealed battery then open the top distilled water vents / fillers and leave the battery box open as a precaution.

 

[ProfJohnL]

Hello Derek,

I dont anticipate a problem with connecting the ALDI charger whilst the battery is still connected to the caravan. The output from the Aldi unit that I have will not exceed the safe working voltage of the 12V system.

The unit I have has a maximum output of 3A which is far less than the caravans internal charger system, so whilst Dusty's advice is not wrong I dont think it will be necessary to open the door.

 

[DerekBrad]

Hello Prof,
Thanks for the reply, but I was concerned about the van still being connected to the mains supply when the charger is on.
Regards
Derek

 

[ProfJohnL]

Hello Derek,

I belive that both chargers will have varoius sensing devices that are designed to monitor the battery condition. As I don't have details of what and how they work I cannot predict what would happen if both chargers were connceted at the same time. In point of fact, I cant see why you might want to have both connected simultaneously, and I couldn't recommend it.

I suggest you run with built in charger and assume it works, but at the first sign of trouble, disconnect Nordlec, and replace it withe th Aldi

 

[waffler]

Beware if you connect the aldi charger with the battery connected to the caravan. The aldi charger will surely output 14.4 volts which will blow your 12 v lights and possibly the fridge electronics. Caravan chargers do so at 13.8 volts which won't blow lamps. Modern expensive van chargers now charge at 14.4 volts when no susceptible lamps etc are switched on.

 

[Damian]

Quote" The aldi charger will surely output 14.4 volts which will blow your 12 v lights and possibly the fridge electronics"

No it will not damage any 12v items!
All 12v items have a tolerance of voltage and will work on any voltage between 10.5 and 15.5v

 

[ProfJohnL]

Hello Waffler.

You may be right about the peak out put from the Aldi unit, however I have not heard about the most recent chargers pushing 14.4V, but I havent looked at the latest regs.

Before 1985 most caravan power supplies were actually pretty basic chargers. Even with a battery in circuit the ripple from the charging current could easily impose peak voltage in the region 18V Most caravan applicnces would function.

 

[DerekBrad]

Hello again Prof,
I would not be having both chargers connected at the same time....I would only use the Aldi charger in the event of the Nordelec breaking down. Referring to your last sentence, I ask the original question: "Should I disconnect the van battery leads before clipping on the Aldi croc clips?" How would one disconnect the Nordelec whilst leaving all other electrics operative?
Sorry to seem a bit thick!
Regards
Derek

 

[ProfJohnL]

Hello Derek,
Ah - now that bit I can't give you chapter and verse on because I don't know the details of your wiring instalation. Suffice to say that for 100% copper bottomed assurance, then yes; you will need to unclip the battery from the caravan when recharging with the Aldi.
But thinking about it a bit more, It all depends on how the Nordelec fails. If it simply goes open circuit, then the addition of the Aldi charger whilst the faulty Nordelec unit is still connected would have no ill effects.
It may be sufficient to simply turn off the mains power to the Nordelec.
Or you may need to physically remove the Nordelec, But with some caravan charger systems thats not possible because the battery circuit is routed through the charger and so you woudl loose battery supply to the caravan.
There could be other options but as I say without acces to your wiring I cannot give you all the options.
You will have to try it and see.
But hopefully you will find teh Nordelec behaves its self this time.

Best of luck

 

[Damian]

Quote "But hopefully you will find teh Nordelec behaves its self this time"

Dont hold your breath,,,,,,,,,they are the biggest single mistake Swift have made fitting them.

 

[DerekBrad]

I couldn't agree more Damian! The problem even manages to put the damper on hols not yet taken!! Fingers crossed that maybe my third unit will be ok. Many thanks , Prof, for the answer that I was really looking for regarding disconnection of the battery from the van before clipping on the Aldi charger (should the occasion arise!)
Regards and thanks
Derek