Votronic 12V StandBy Charger (DC-DC Trickle Charger)

  (14 Reviews)
Price:  £42.50   (£35.42 Exc. VAT)

Product code:  P01899
Brand:  Votronic
Voltage  12-12V
Current Rating  3A



13 in stock

The Votronic StandBy Charger enables simultaneous trickle charging of your starter battery whilst your leisure / auxiliary battery is being charged from a mains charger, solar panel or generator. This is ideal if the charging source connected to your leisure battery has only one output, but you want to be able to provide a maintenance charge to your starter battery to keep it topped up.  Ideal for over-wintering campervans, motorhomes or boats.

Activation of the unit is automatic and it only operates when it senses a charging voltage at the leisure battery, keeping the batteries electrically separated otherwise. The amount of current diverted from the charging source will vary depending on the charging conditions but it is limited to 3A maximum. The starter battery cannot be over-charged because the charging voltage is reduced by 0.6V before reaching the starter battery.

Fitting is very easy and does not require any re-configuration of existing electrical systems. The unit simply needs small gauge cable and suitable fuses to be fitted between its terminals and the positive terminals of the two batteries. 

Suitable for use with lead-acid batteries only (not for use with lithium technology) where both batteries have a nominal system voltage of 12V.

Designed and manufactured in Germany with a 3-year manufacturer's warranty.

Further information

  • Use 1.5 - 2.5mm² cable with 10A fuses
  • Negative terminals of both batteries must be electrically connected (directly or indirectly)
  • System voltage: 12V DC
  • Output current: 3A max.
  • Battery types: Lead-acid only (flooded, sealed, AGM, gel etc.)
  • Working temperature: -20 to +40°C
  • Protection class: IP20
  • Overall dimensions: 90 (L) x 60 (D) x 38 (H) mm

Part Number:  C8451

Bar Code:  4250683601988

Average Rating (14 Reviews):  
Write a Review and share your opinions!

Peace of mind for £40
27 January 2024  | 

Title says it all. You can pay loads for dc to dc charging, and in some cases that might be perfectly justified. For my setup - Vivaro campervan used at weekends through the season - what I needed was a simple way to have my leisure battery (charged by 200w solar roof panel) take care of my starter battery as well. We all know the dreadful sound of a diesel trying to spin over from a flat battery following a few weeks of not being run! As far as I can tell this little box is doing just that.

I used the split charge +ve feed wire from my starter battery, popped this little box in on the starter battery side of that feed (NOT the relay controled side) and ran a new wire to my solar-charged leisure battery. Van has started first time ever since... just two wires to consider!

Make sure you read the instructions and all will be well (don't forget to fit the supplied inline fuse for safety.)


Thank you for this great review!

Voltronic Charger
25 February 2022  | 

Simple to fit and does what it says on the packet!

motorhome leisure
11 February 2021  | 

Excellent for keeping engine battery alive from solar/leisure battery.

All good
03 February 2021  | 

Does the job. Is keeping the starter battery healthy from the solar panels.

Great addition to any motorhome
06 January 2021  | 

This is the best bit of kit that I have bought for the price. Wired it in and it instantly started working. Now when I have it on electric hook-up it keeps both batteries charged up. Very pleased with it especially for the price.

Excellent Product and Service
08 December 2020  | 

I had installed a solar system for my leisure batteries but as we've not got out much this year, my starter battery went flat - this little gizmo allows the energy from the solar to also trickle charge the starter battery. 12Vplanet were ace - delivery was before expected date - all good, added to my favourite vendors and would recommend.

Just the job
19 November 2020  | 

This is the second one I have bought for our campervans. They appear to work well, keeping the starter battery charged. Obviously it all depends on the size of each battery and if the inbuilt charger is switched on. So, in summery as long as the charger is on then the starter battery will receive a TRICKLE charge.

Great product
11 November 2020  | 

Works very well and easy to install, using on motorhome to keep cab battery charged

Motorhome Leisure and Starter Charge system
07 October 2020  | 

This allows the Solar panel to charge the Leisure battery and a lesser amount of charge is diverted to the Starter battery.
Very useful to maintain starter battery, with the vehicle alarm and tracker systems draining down the Starter battery. Good product, great idea.

Great service
06 October 2020  | 

The service 12volt planet gave was excellent. Order arrived quickly and they were very helpful over the phone giving me advice as I needed it.Would highly recommend

Read all 14 customer reviews...


Votronic is a German company that has been designing and manufacturing high-end electrical and electronic products for the camper, caravan, marine and 'blue light' vehicle markets since 1987. Offering charging, solar, inverter and control technology, its focus is on innovative and extremely reliable products.

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Business Hours: Mon - Fri | 9am - 5pm
CALL Sales & Support: 01844 885100
Email: sales@12voltplanet.co.uk
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