CTEK D250SE Dual Input DC-DC Charger & MPPT Solar Controller

  (3 Reviews)
Price:  £271.07   (£225.89 Exc. VAT)

Product code:  P01901
Brand:  CTEK
Current Rating  20A
Open Circuit Voltage Rating  23V



14 in stock

Note:  Cables  and fuses not included. Please download installation instructions to determine correct cable size and fuses for your application.

Using award-winning Swedish technology, the CTEK D250SE is a fully automatic, 5-stage DC-DC (battery-to-battery) charger and MPPT solar charge controller in a single, compact unit and is the successor to the hugely popular D250SA model.  It enables you to charge a second lead-acid or lithium battery on the move, ensuring it's ready to power your 12V systems when you reach your destination. It has separate inputs for alternator and solar, allowing your battery to be charged from either of these power sources or a combination of both, prioitising the solar input to ensure maximum efficiency. 5-stage, temperature-compensated charging with selectable charging profiles ensures that your battery is maintained in the best condition possible and its service life maximised.

The D250SE can work with either conventional or 'smart' (Euro 5 / 6) ECU-controlled alternators and can provide up to 20A of current to charge the second battery. When the alternator is not running, the charger isolates the starter battery from the second battery (without the need for separate diodes or VSRs) to ensure that one cannot be discharged from the other. The solar input enables a second battery to be charged at up to 20A via a built-in controller that uses the latest MPPT technology to maximise the solar energy harvested from the panel. Once the second battery is fully charged, the D250SE will use the solar input to trickle charge the starter battery to ensure that it is maintained. The solar input can also be used to connect a wind generator instead of a solar panel.

The charger has ­selectable charge algorithms for different battery types (Wet, Sealed, Ca/Ca, AGM, EFB, GEL, LiFePO4, Li-Fe, Li-iron, LFP) with two settings for AGM (14.4V & 14.7V) and a temperature sensor to ensure that the charging profile is always ­optimised for the battery temperature.


  • Fully automatic, 5-stage charging 'on-the-move' 
  • Optimised charging for maximimum battery life
  • Dual inputs from alternator and solar (or wind) for combined charging
  • Works with Euro 5/6 Smart alternators and conventional types
  • Suits all lead-acid and lithium batteries
  • Adjustable charging profiles for different battery types
  • Can be used with battery capacities of 40 - 300Ah*
  • MPPT solar controller technology
  • Temperature-compensated charging
  • Splash and dust-proof (IP65)
  • 2-year manufacturer's warranty

Further info

* For faster charging, this unit is best used with batteries up to around 110Ah capacity.  For larger batteries please look at our other battery-to-battery chargers.

Cables and fuses not included. Please download installation instructions to determine correct cable size and fuses for your application.

Please note: If used with a lithium battery and the BMS shuts down the inputs/outputs to the battery (e.g. in an under-voltage condition), this CTEK unit will not 'wake up' the BMS and so will not be able to charge the battery (this is because the CTEK unit needs to see a minimum battery voltage to commence charging). An external charging source (e.g. mains battery charger, solar charger) will need to be used that can supply a 'wake up' voltage to activate the BMS and allow re-charging.

Warning - when using with solar panels, the panel open circuit voltage must not exceed 23V DC or the CTEK unit may be damaged and the warranty voided. Do not use with panels connected in series.  If using multiple panels, connect in parallel and ensure open circuit voltage is less than 23V DC.

  • Input voltage: 11.5 - 23V DC (max. open circuit solar panel voltage 23V - DO NOT EXCEED)
  • Input current: 25A
  • Output voltage: 14.4V DC max. (Normal), 14.2V DC (Li-Ion), 14.7V DC (AGM)
  • Output current: 20A max.
  • Max. current at elevated temp: 16A @ 30°C, 13A @ 50°C
  • Standby current draw: less than 1Ah / month
  • Ripple: less than 4%
  • Operating temperature: -20°C to +50°C
  • Temperature compensation: 23mV / °C
  • Lead-acid battery types: Wet, sealed, EFB, Ca/Ca, AGM, GEL
  • Lithium battery types: Li-FePO4, Li-Fe, Li-iron, LFP
  • Battery capacity: 40-300Ah
  • Overall dimensions: 192 (L) x 110 (W) x 65(H) mm
  • Ingress protection rating: IP65 (splash and dust-proof)
  • Weight: 0.7kg
  • Solar panel power: 50-300W (max. solar panel open-circuit voltage 23V DC)

Part Number:  40-315

Bar Code:  7340103403159

Average Rating (3 Reviews):  
Write a Review and share your opinions!

Worth every penny!
01 December 2020  | 

Easy to install. Very well built. Boosted my CitroŽn Relay smart alternator charge from 14v to 14.7v. Recommended.

Great product & service
26 October 2020  | 

Great product & service

Excellent Product
17 June 2020  | 

Easy to install charger that allows you to tailor it's out put to your system. I have a smart alternator so I connected the red lead. I have a Gel Battery so i left the black lead detached. Manages the alternator and solar panel charge. Great unit. 12v Planet very good service.


CTEK is a global leader in battery management technology with a huge following in the campervan, motorhome and overland markets. This innovative Swedish company continues to improve and shape the battery management industry with its research and development, which is at the heart of all its products.

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CALL Sales & Support: 01844 885100
Email: sales@12voltplanet.co.uk
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