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SamP

Psu

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Hi

 

I suspect the PSU is failing in my van. My battery is never getting fully charged and after a couple of hours of using lights etc they are going dim and the pump struggles. Battery readout is down to about 9 volts. The reason I believe it is the PSU is because it should also be able to act as a transformer to power the vans 12v system without a battery connected. If I do this the read out on the display is lower still and the 12v system becomes next to useless. The next morning the battery level will be up to around 12v and will be fine again until we put a heavier load on the battery in the evening.

 

Do you think my logic seems reasonable? I was thinking of buying a cheap trickle charger to put on the battery a few days before we next use the van and then taking it with us and leaving it on whilst away, and if this resolves the issue I'll replace the PSU with one of these https://www. amazon. co. uk/Amperor-Leisure-Battery-MV3-180/dp/B001CVUXKI

 

Thanks

 

Sam

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I suspect your battery needs replacing. take it to somewhere like Halfords and they will check it for you.

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Indeed my thoughts on battery life. ..how old is it?...did it come with the 'van?

 

geoff

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You will be doing the battery no favours with using it without recharging. Get that battery on a good charger asap if not tonight!

 

A depleted battery might raise from 9V to 12V overnight with a rest, but should be 12. 7V fully charged. Even leisure batteries don't like being left discharged for extended periods.

 

Your description does sound like the psu has done one of the following:

Failed,

Lost its mains supply (check mains fuse, switch, mcb and input volts terminals (with an ac meter if you know how to do so safely)

Blown a fuse between its output and the battery / rest of the 12V systems (check circuit diagrams, 12V fuse panels etc,.,)

 

 

If not competent / practical minded get a service technician (AWS mobile?) to check it out for you and diagnose the fault, and how to best fix it.

 

The Swift technical bods on their forum may have specific knowledge on the precise kit fitted in your caravan and the likeliest fault points?

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Doesn't sound like the battery if the 12v rail is low when the battery is disconnected. Don't know your van, some older models needed a battery, but all modern vans I've come across the PSU will provide a decent supply without a battery.

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Battery is a 110 amp and is coming up to 5 years old, so I know the battery is a possibility. But in my mind the symptoms point to the PSU, though I suspect I will end up having to replace both PSU and battery!

 

I can see from the readout on the control panel that the PSU is supplying voltage to the battery as when you switch the mains off the voltage drops right down. Will bring the van home on Wednesday and hopefully get sorted, just wanted to see a couple of people thinking along the same lines as me.

 

Thanks

Sam


Doesn't sound like the battery if the 12v rail is low when the battery is disconnected. Don't know your van, some older models needed a battery, but all modern vans I've come across the PSU will provide a decent supply without a battery.

Yes I always used to be able to run the 12v system perfectly without a battery, but not any more!

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I used an Aldi charger for a few months when the van PSU failed and have carried one since for emergencies. It's only 3A or so thus not a replacement. I disconnected the PSU first.

I assume you have actually disconnected the battery to test out the PSU?

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I used an Aldi charger for a few months when the van PSU failed and have carried one since for emergencies. It's only 3A or so thus not a replacement. I disconnected the PSU first.

I assume you have actually disconnected the battery to test out the PSU?

I used a previous generation smart charger, rated at 4 amps, for nearly 30 years - first caravan had no PSU - this arrangement worked better than the onboard PSU in the second.

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I don't know what charger your swift has, but the 2017 model Conqueror has a 3 stage 25amp one, Swift say not to be used with out a battery.

 

Same a Tinshack i also carry a Lidle charger for emergencies, its surprising light in weight.

The Amperor is a good choice, and can be used without a battery according to Amperor, but for the little extra i would go for the 25amp version.

Edited by xtrailman

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I think I would change the battery first as a quick test . As said most batteries sit in storage at winter discharged which they don't like .

 

 

2007 PSU ? Not sure if it would playing up in that time .

 

 

 

Dave

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Try connecting your car battery up to the charger in the caravan that way may prove the psu faulty or not.

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The battery will be toast if it's spent any time at those sort of low voltages so I'd replace that as a matter of coarse, if the psu hasn't been completely knackered by trying to maintain a rubbish battery it might soldier on for a bit, I'd just fir the amperor (which I have done on ours) otherwise it'll just go kaput when it's inconvenient and not when you have the luxury of changing it on the driveway!

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I don't know what charger your swift has, but the 2017 model Conqueror has a 3 stage 25amp one, Swift say not to be used with out a battery.

And yet during the service on our last van, a Swift, one of the tests was measuring the PSU output with the battery disconnected. Maybe they disconnected more than the battery. Easiest test is as suggested, just pop another battery in temporarily if in any doubt.

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And yet during the service on our last van, a Swift, one of the tests was measuring the PSU output with the battery disconnected. Maybe they disconnected more than the battery. Easiest test is as suggested, just pop another battery in temporarily if in any doubt.

 

The swift has a battery for the alarm and another for the EC600 unit, so unless the charger is permanently on power these batteries will start to discharge.

 

I believe this is the reasoning behind it.

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Well I've got the Amperor unti here ready to fit tonight. Had another play around with it today. With the battery disconnected it shows 14v on the readout, as soon as you switch on a single light it drops straight down to 8v and the light is very dim. So I'm convinced the PSU is shot. The battery's not been left to go flat, the PSU does charge it up when left with no load overnight, thought I suspect it's not holding charge for as long as it should so the battery will be replaced next month when I have a bit more cash. I'd rather do it this way round so that I'm not putting a new battery onto a knackered PSU as we are out in the van this weekend.

Edited by SamP

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Well I've got the Amperor unti here ready to fit tonight. Had another play around with it today. With the battery disconnected it shows 14v on the readout, as soon as you switch on a single light it drops straight down to 8v and the light is very dim. So I'm convinced the PSU is shot. The battery's not been left to go flat, the PSU does charge it up when left with no load overnight, thought I suspect it's not holding charge for as long as it should so the battery will be replaced next month when I have a bit more cash. I'd rather do it this way round so that I'm not putting a new battery onto a knackered PSU as we are out in the van this weekend.

 

If switching a light on (which draws current) causes the PSU output to drop substanyially then connecting the PSU to the battery (which also draws current) will likewise cause the PSU output voltage to drop so it won't and won't be able to charge the battery.

 

However I would ensure that it is the output of the PSU that is dropping and that it is not the caravan wiring or connections that are the problem. If you have a voltmeter (which your text suggests you do) connect it to the output connector of the PSU whilst it is still connected to the caravan and look for change there under load. If the voltage drops it is the PSU, but if it doesn't go looking for a connection problem. One thing to look at carefully is the in-line fuse between the battery and PSU and check it is in good condition - corrosion could cause a resistive connection which will result in voltage drop.

 

Given the way that switched mode power supplies work it is unlikely to be a mains supply problem so either the switching section of the power supply or (more likely) the output regulation has gone for a burton. In you position I would change the PSU first.

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Well it's changed and seems to have resolved the issue. Took a bit longer than expected as I ended up stripping down the existing PSU and removing the charger just leaving the 230V as is. Connected some new mains flex to the existing power switch for the battery charger (which is part of the original PSU) and ran it down to the battery box where I monunted the new charger. I wanted to keep it as OEM as possible and keep it on the existing power switch. Nice neat job and the lights don't flash when the pump runs now! New battery next month.

 

Thanks for all your suggestions.

 

Sam

Edited by SamP

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New battery next month.

I'd monitor the existing battery - having recharged it properly first. OK it has been abused a bit by the original charger-psu failure but - unless you do a lot of off EHU caravanning - it may still hold charge enough for your normal use?

 

I'd want to be sure I needed a new battery before shelling out on one, personally ;)

 

http://www. batteryfaq. org/ is worth a read through wrt to measuring voltages on batteries etc. ,.

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I'd monitor the existing battery - having recharged it properly first. OK it has been abused a bit by the original charger-psu failure but - unless you do a lot of off EHU caravanning - it may still hold charge enough for your normal use?

 

I'd want to be sure I needed a new battery before shelling out on one, personally ;)

 

http://www. batteryfaq. org/ is worth a read through wrt to measuring voltages on batteries etc. ,.

The big test will be how long the motor mover is usable for at the weekend!

Edited by SamP

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I've never had a mover expire a battery, even at 9 years old.

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