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Dumb question time again!
The battery on the Duchess is low, good enough to run the systems but not enough to crank. Can I hook up my (not particularly powerful) charger straight in there and avoid all the tedious window setting, radio codes etc?
It isn't a trickle charger, but seeing as you can hook up a whole car to jump start I don't see why it would be an issue except various google searches warn against this.

So, I thought I'd ask experts instead of Google :)

edit: very low :( 8.1V

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Due to low mileage I do that on a regular basis and, so far, nowt has been damaged. 8 years and counting!

However my charger is an old Woolworths (remember them) metal box unit of may be mid - late 1960's vintage up gunned with a mil-spec low ripple transformer and high power diodes around about 1980 (ish) when the original innards went pear shape. When things have been lying around in lab stores for a decade or more its a shame not to actually use them. Happily bounces the (supposed) 6 amp max reading meter off the end stop for the first hour at full charge rate! One day I might actually measure what it pumps out on high range. Voltages are correct as its what the transformer was made for with high and low output windings for both 6 and 12 volt (nominal) batteries. Lord knows what the transformer actually cost Her Maj back in the day. Or what the equivalent would cost now. Something scary no doubt.

Clive

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I've got a very elderly boost charger. It was originally used to charge the batteries used to power old valve based Pye Westminster two way radios that were installed in all mail trains after the great train robbery. My predecessors at work would meet the mail train, provide it with fully charged batteries every evening and swap them for the ones that had been there since the previous day and get them charged ready for the next day. I sort of inherited it..... According to the meter on the front, it's capable of charging at up to 30A but I tend to keep it down below 5A so I don't cook anything and have never had a problem even on a P38. If I crank it up, it'll get a battery from flat to capable of starting the car in half an hour but I only do that if the battery is disconnected though.

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Just buy a trickle charger Morat....mine's an Accumate Pro - 12v/24v, polarity protection built in. Run it for 5+ years, good piece of kit

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I’ve just changed a battery in the car, onlyused 3 amps but it did the job no problem

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Thanks Folks!
I'll look up the specs on my charger again, but it's only a tiddler with a 10A fuse on the 12V output. A trickle charger is definitely the correct solution. Maybe even solar in the current weather?

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Solar isn't likely to do anything here without a big panel and a proper controller.

I've had various power supplies connected to mine without problem, including a cheapish ring 25amp noisy thing. Could hear the 50hz hum through the stereo but the car wasn't bothered. That said I prefer using a nicer supply, and often have mine connected to my Ctek when I know it'll be sat for a long time. Despite no RF interference problems. I don't leave either of my cars without the ctek if they're going to be left a long time :)

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A smart charger is best. It splits the charging into stages, usually 4 stages but sometimes more and it adjusts itself accordingly.
The last stage puts the voltage up by about 1 volt ( to around 14.5v from memory) to squeeze the last bit in to give it 100% charge.
You can leave them connected continuously without damaging the battery. It can also often resurrect a duff battery.

Ctek are good, I have a small 3 amp one, but they are overpriced. I bought a couple of smart chargers from Lidl I think it was (maybe it was Alde) for about £12. Been very good. I use one permanently on the caravan in the drive.

A tip I learned on one of the forums was to charge the car through the white 12S towing plug. I made up a special plug for this purpose and I leave the charger, which is fairly waterproof, under the car. Handy if you have a flat battery and can't get in the boot.

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Mine is a smart charger, with four stages - just not a huge one. I'm thinking Solar just to keep things topped up and avoid running cables out the front of the garage. I've seen THIS one on Amazon that connects through the OBD port.

Right, I'll hook it up tonight and see how it goes!
Cheers all.

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But you don't need a huge one and a four stage smart charger will do a much better job than a solar panel. I bought one of the Lidl copy of a Ctek for just over a tenner which I connected up to trickle charge a battery. Worked fine for a while but then decided it was going to run flat out all the time, toasted the battery and got so hot the plastic casing melted. So I'd be very wary of leaving one of them connected permanently.

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Ctek chargers are expensive but I'd trust them more than a cheapie left connected unattended - for exactly that reason. Mine is the MXS 5.0 - middle of the road model I think. What's nice is it can be used to (slowly) charge a dead 130ah battery, or small 7ah SLA battery without causing it to swell by using the 'motorbike' ie low current setting. It has brought a couple of dead dead SLAs back to life.

I have the 50amp anderson connector in the load space of my P38 that is used for the Waeco fridge - so I made up a Ctek to anderson adapter, and then sit the charger in the load space and run an extension lead in through the tailgate seal, which can close on the cable without crushing it or preventing the upper tailgate from closing properly.

So long as I don't forget about it and drive off....

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Not completely sure about the LiDL "Ultimate Speed" branded smart chargers. Good value but I left the Norton connected to one over winter the other year and it killed the twin 14AH batteries. So only got a single summers use out of them.

Now I tend to use the LiDL chargers in short bursts, a day or so max every few weeks to bring the bike and generator back up when they are not being used. (Had the generator 5 years now and only test run it. Its one of the old whisper quiet Honda ones so if I do need it its not going to upset the neighbours.) However I imagine our big Range Rover batteries are a lot more tolerant than itty bitty bike ones.

Clive

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Well, I've snipped the blue/white wire on the switch side of the connector to stop the door latch saying the door is ajar (connects to the purple/white wire on the door side). Sadly the little clip that keeps the loom out of the way of the window must have fallen out so now there's some taping up to be done :/

But, now I can shut and lock the vehicle without the alarm going off every few hours and hopefully that will let the BeCM go to sleep and let the battery catch up again!

Still got the viscous to do... but I'm taking her Ladyship out tonight for her birthday. I don't think that the smell of ATF would be appreciated :)

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My Accumate Pro ( smart charger) has been connected for 4+ years continuously in the garage beneath my house to recharge a 24V Toylander which often needs a full recharge after use. It has never caused any issues. Often used on the P38 too. You can also buy multiple connectors ie other than Croc clips, perhaps not a towing socket, although I'll have to investigate