Message Forums

Have you checked the water level?  Try charging the battery so it shows full and then put the meter on it whilst it is under load.

Sorry I can't be of more help.

1. Testing the mains with your multimeter will not tell whether it is calibrated on DC low voltages. A different set of internal components is used. Ina any case, mains voltage can legally chage by as much as 15%. Our mains supply at home is actually 250v. However mulimeters rarely need calibration and for this use, accuracy is not important.

2. I assume the reading of 14.5volts was when the battery was connected to your charger. This would be the charger voltage. 

I think there could be 2 possibilities. As I have said in another post, most battery chargers won't charge a fully discharged battery, and your charger would simply show charged. You would need to use a good intelligent charger which will pulse charge your battery to recover it. Pays for itself with just one use. If you have been on EHU each time, the 12v electrics would work off the caravan charging system, but that charger would not charge the battery, so it will remain discharged.

If the battery is charging each time, then you must have something in the caravan which is slowly draining the battery, and it is a slow and steay process to check through the van for each possibility. An easy way round this would be to disconnect the battery each time.

Quote: Originally posted by freeatlast on 09/12/2009

---

1. Testing the mains with your multimeter will not tell whether it is calibrated on DC low voltages. A different set of internal components is used. Ina any case, mains voltage can legally chage by as much as 15%. Our mains supply at home is actually 250v. However mulimeters rarely need calibration and for this use, accuracy is not important.

2. I assume the reading of 14.5volts was when the battery was connected to your charger. This would be the charger voltage. 

I think there could be 2 possibilities. As I have said in another post, most battery chargers won't charge a fully discharged battery, and your charger would simply show charged. You would need to use a good intelligent charger which will pulse charge your battery to recover it. Pays for itself with just one use. If you have been on EHU each time, the 12v electrics would work off the caravan charging system, but that charger would not charge the battery, so it will remain discharged.

If the battery is charging each time, then you must have something in the caravan which is slowly draining the battery, and it is a slow and steay process to check through the van for each possibility. An easy way round this would be to disconnect the battery each time.

---

i check mine regular in the van on the drive and the constant charge reading is 13.5v .having said this it is connected to EHU for 6 hours a day on a timer.just possible your meter in the caravan on the wall is faulty and giving a false reading.a faulty charger can also drain a battery very quick.

Have you checked the cells with a hydrometer

I had a problem with my leisure battery but after adding 1 litre of distilled water it charged up OK

£1.96 £2.25 inc VAT

Battery Hydrometer B55 Use hydrometer to give a fast and accurate reading of the battery condition.

Quote: Originally posted by michael on 09/12/2009

---

i check mine regular in the van on the drive and the constant charge reading is 13.5v .having said this it is connected to EHU for 6 hours a day on a timer.just possible your meter in the caravan on the wall is faulty and giving a false reading.a faulty charger can also drain a battery very quick.

---

Quote: Originally posted by JohnG on 09/12/2009

---

Have you checked the cells with a hydrometer 

---

Quote: Originally posted by steve2020 on 09/12/2009

---

Quote: Originally posted by JohnG on 09/12/2009

---

Have you checked the cells with a hydrometer 

---

No John I have'nt tested using a hydrometer, I may have to try It if i can't get any joy with other means.

thanks

---

I've got the same problem with a 110amp battery. It was new on the van in May this year, had 3 weeks of use in Cornwall back in August & won't hold its charge if left on the caravan. I've charged it in the garage & intend putting it back on the van to see how long it'll stay up for. Last time it wouldn't even light up the control panel in the van. I can see it going back under complaint because it's no use to me if it won't power the mover to get the van off the drive.

BB

Quote: Originally posted by AndrewK on 10/12/2009

---

If some of you guys have multimeters, switch everything off in the caravan then use the multimeter to measure the current drawn from the battery.   In my van, a 2006 Burstner, it's about 120mA. This would flatten the battery in 2 or 3 weeks if I hadn't fitted a battery isolator when the van was new. A Lunar Saturn I had previously has a similar current drain. My bet is that many caravans do and it is this that causes your battery to go flat in storage.

I don't actually know what causes the current drain. It's an order of magnitude too high for the aerial amplifier - but just about right for the coil current of a relay, probably in the 12V power supply - so maybe it is that.

If you discover that you have a similar problem then either disconnect the battery every time you put it in storage or turn off the caravan's battery isolator if the van has one. Alternatively, you could buy a battery isolator - you can get 100amp isolators on ebay pretty cheaply.   If you do that, it is then a practical proposition to buy yourself a small solar panel (rated at say 2 to 5W), connect it to the battery side of your isolator and leave the battery in the van permanently.

I went up to the Burstner earlier today and discovered that my 110ah battery was flat as a pancake. The van is in storage and I haven't been near it for a few months. Normally it would have been fine as I have an isolator and a 5W solar panel connected, but not if you forget to open the battery isolator!!!   When I got it home, I measured the battery voltage with a DMM - 2.67V. I've put it on charge, but the battery is probably totally goosed.   It is around 5 years old, so maybe it's time I bought a new one anyway.

Andrew

Post last edited on 10/12/2009 19:08:15

---

You can recover them if they go completely flat if you use an intelligent charger with a pulse charge facility. I am still using a battery 6-7 years old now which has been fully discharged a couple of times. Worth a try.

Quote: Originally posted by AndrewK on 10/12/2009

---

If some of you guys have multimeters, switch everything off in the caravan then use the multimeter to measure the current drawn from the battery.   In my van, a 2006 Burstner, it's about 120mA. This would flatten the battery in 2 or 3 weeks if I hadn't fitted a battery isolator when the van was new. A Lunar Saturn I had previously has a similar current drain. My bet is that many caravans do and it is this that causes your battery to go flat in storage.

I don't actually know what causes the current drain. It's an order of magnitude too high for the aerial amplifier - but just about right for the coil current of a relay, probably in the 12V power supply - so maybe it is that.

If you discover that you have a similar problem then either disconnect the battery every time you put it in storage or turn off the caravan's battery isolator if the van has one. Alternatively, you could buy a battery isolator - you can get 100amp isolators on ebay pretty cheaply.   If you do that, it is then a practical proposition to buy yourself a small solar panel (rated at say 2 to 5W), connect it to the battery side of your isolator and leave the battery in the van permanently.

I went up to the Burstner earlier today and discovered that my 110ah battery was flat as a pancake. The van is in storage and I haven't been near it for a few months. Normally it would have been fine as I have an isolator and a 5W solar panel connected, but not if you forget to open the battery isolator!!!   When I got it home, I measured the battery voltage with a DMM - 2.67V. I've put it on charge, but the battery is probably totally goosed.   It is around 5 years old, so maybe it's time I bought a new one anyway.

Andrew

Post last edited on 10/12/2009 19:08:15

---

Cheers Andrew

I think you've hit the nail on the head regarding something slowly draining the battery over a few weeks eg the coils in relays. I'm going to buy myself an isolator switch I'm sure this Is the answer. To work out how much current is being draw do you disconnect the battery to see the exact reading then reconnect and apply the multimeter then subtract the new reading from the disconnected battery reading?

-------------

Quote: Originally posted by steve2020 on 11/12/2009To work out how much current is being draw do you disconnect the battery to see the exact reading then reconnect and apply the multimeter then subtract the new reading from the disconnected battery reading?

---

---