Testing your battery

It's not just Halfords who have the current loading tool necessary for testing a battery's condition, your nearest tyre and exhaust centre will also have one - assuming that they sell battery's, which most do.

The C&CC have an excellent guide to leisure batteries 

http://www.campingandcaravanningclub.co.uk/helpandadvice/technicalhelp/power/a-guide-to-leisure-batteries/

Perhaps one of the Mods could make it live. The pamphlet is also downloadable as a .pdf, We keep a copy in our caravan.

I might have missed the point here but here goes:-

Switch meter on.

Select DC.

Press the 'Range' button 3 or 4 times (It's 4 times on my meter).

Clamp or touch probes on to the battery....observe the + and -.

It should read about 12 volts......if you get a silly reading it's probably the range. Tap the button and keep trying until you get a sensible reading.

12.5 volts plus is OK.

12.4 volts and below requires charging.

After charging it takes many hours to 'settle' and give a correct reading.

If I have not understood your original question....Sorry!

PS. It makes a lot of sense to check your battery on an add hoc basis.......a drop test should be the last resort which is normally not worth the bother!

I think EJB that you may not fully understand the issues being discussed and which the OP didn't understand well enough to ask the question. What you describe is a simple voltage test which may well give a favourable reading eg 12.5V even though the battery has lost the ability to support a load for a reasonable period, for example 85Amps for an hour or 85 hours at 1 Amp. In practice the discharge rate isn't linear, but my example will do. The discharge test which people are referring to is used to ascertain the battery's ability to deliver and sustain a current loading (in Amps, not volts). Anyone planning to go off EHU for a few days, without a means of topping up such as a solar panel, could find themselves with a flat battery, sooner than hoped, despite having charged it to above 12.5V immediately before departure If the battery's capacity in Ampere hours has diminished.

I will be interested to know exactly what the OP was asking - ....

Thanks for your advice Jenny.

Having made simple voltage checks in caravans and MHs for over 50 years it has never let me down.

I don't want to extend my comments any further as they are quite understandable and concise!

As a retired spark I don't need to make things too complicated!

Drop testing a battery went out of vouge years ago.  I haven't used one for at least 20 years, we use conduction testers now far more accurate.

Our golf pro was keen to find a way of testing trolley batteries and asked my advice. In theory there are instruments that will do this but batteries are all slightly different and the tests are not reliable. in short, the method other pros use involves a discharge test over a few hours using a resistance test bank. This is probably the best way as it simulates something like the actual conditions of use.

I am not sure that a drop test is ideal for a leisure battery as it is not designed for this. It also needs expertise in interpretation.

A voltage test after charging, repeated over a week or so will tell you if it is holding charge for a short period (look to maintain 12.7 volts) other than that I have tried a 12 volt halogen bulb and plotted the discharge Voltage but it is trial and error.

I think that if you take the battery off the van then charge it with a decent charger like a Ctek, you should get an idea of how long it is lasting off EHU. Most Caravan chargers will not recharge a discharged battery properly when on EHU.

Hi all

 Thank you all for your comments however I am now more confused. 

We are totally new to caravaning so please excuse my stupid questions. 

We a have 2 berth sprite alpine with motor movers fitted and my main concern is after we have been on rallys will my motor movers still get our caravan on the drive so wanted to be able to test the battery 

Take care

Andy

Perhaps Andy you just go and do what you want to do and find out, but have a (borrowed) spare battery waiting at home just in case.

If your car & caravan are wired correctly, your caravan will be charging while on your way home.

As jennyc suggests, even a battery showing 12.7 volts on the meter could still be on its last legs, it depends on how long it takes to discharge. Think of a mobile phone, when new, the battery will last longer than it does when it's 12/18 months old. Your car's & caravan's battery is the same.

Getting your caravan onvthe drive when you get home? You've always got your car