CTEK D250SA - 12v 20A DC to DC Charger and MPPT Solar Controller. £100 for a Used Ctek D250SA unit in good working condition and works for Lead Acid batteries including AGM. Manual can be downloaded from there web site but it's very easy to do (NOTE:This CTEK 250SA unit is not compatible with lithium batteries.) This CTEK 250SA allows you to charge your vehicle leisure battery from your engine alternator and from the solar panels on your roof simultaneously. When the leisure battery is full, it will start to charge your engine battery from solar panels. This was removed, working from my camper van. I have upgraded to a Renogy Lithium Battery and Renogy 30 DC-DC Mttp, (i.e. a charger that could handle charging a lithium battery)
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