caravan charger questions

[jayjay]

Hi Ant (or anyone else who could help!!)

I have a charger in the front storage thingy on my caravan which is a Lucas charger. It has a rocker switch with three settings - on/off/battery. It has a connection to the leisure battery with clamps and I wondered whether this charges the battery whilst on EHU and which setting to put it on if so.

I've connected the EHU and the needle is moving from zero (in the red) on the battery switch, just wondered if this was actually charging the leisure battery (also housed in the storage thingy). It doesn't move on the off position (not surprising as off is off) and also the needle doesn't move if I switch it to on. But it starts going up when switched to battery.

Sorry if I haven't explained myself very well, first time I've seen one of these.

The caravan also has twin electric sockets although I only have single (for the indicators and so on... I believe that the twin socket only keeps your fridge going on 12v whilst you're moving anyway, so I don't think it matters if I don't have twin electrics whilst on the move - or is that how the charger works?

Thanks for any replies! Here's a pic of the gadjet....

[peterholden]

Ant will no doubt have more information about your charger but in general british caravans tend to be fitted with the twin connection to the car. The black (called 12N) provides all the road type connections such as lights and the grey (called 12S) provides the habitation side of things - that is power for the fridge and power to the leisure battery to charge it. Both these systems require some kind of relay at the car engine end so that power is taken from the alternator. The wires also should be thicker than most other wires to reduce the voltage drop.. This side of the electrics can become troublesome with age because of poor connections in the plug/socket and corrosion where wires join leading to high resistances. The charging the battery from the car bit is only really successful if you are on the move regularly. If you are going to use EHU I would keep it simple and not bother with the grey. By the way most older continental caravans (apart from really expensive ones - usually german) don't have the grey electrics.

[jayjay]

Thaks for the info, Pete.

This is a Dutch Kip and 1982, so high spec then as it has both the black and grey connectors! However, at the car end I only have the black or 12N to connect as I only have a towbar with single electrics.

What I was wanting to know was if this charger charges the leisure battery whilst on EHU. I plugged in the EHU today and switched it to battery on the rocker switch and the needle went up a bit, so I was just wondering if it would charge from the EHu when connected and standing (so I can charge before I go and charge when I'm pitched on site), rather than charging from the car whilst on the move.

[peterholden]

If the Lucas thingy is indeed a working charger it will charge your battery whilst on hook up. It may be that whoever imported the caravan to the UK fitted the greycables etc - some importers but not all did that to appeal to the british market. we used to have a Freedom caravan and when we bought it in 1995 we were asked if we wanted their"UK" electrics package and we said no - the only bit that we chose was the part that allowed us to charge the battery from the car. we never had EHU on that van.

[ant]

Hi Jay Jay.
I'm afraid I don't think your thingy is a charger, from the picture it looks like a switch and metre that allows you to charge from the car when travelling ( on) switch it all off (off) and use the caravan battery for lights etc ( Battery).
I suspect if you had a 12S cable connected and turned the thingy on with the car running the metre would show the charge voltage. When you switch it to battery the metre shows the battery condition.
Ant

[jayjay]

Thanks for that, Ant (and Peter).

I'll have to use a trickle charger for now then, unless I get a grey lead connected to my car... not that I'm that bothered really as I'll have ehu most of the time.

I'm just trying to find out how things work! It's so different (and seems more complicated) than the little campervan!

Pete, it would make sense that this has been upgraded to twin electrics as it doesn't have a fridge just yet. I've bought one ready to put in, but the leisure battery looks like a later addition as well, so that would bear out what you said about older continental styles.

Thanks for all your help!

Will be back with more stupid questions later.... Wish I could get hold of a manual for it, life would be much easier.