Important notice.

Please be aware that the AL-C20 and AL-BK20 are no longer available and as some parts are obsolete repair of these products is often not possible. Both of these item have been superseded by the BC-520. For more information or a price please use the contact/enquiry form.

The ArSilicii range of products are well made and sophisticated, but they are not designed to support a battery past it's best and/or an enlarged battery bank. The AL110, AL310 and AL-C20 are no longer current products. These have been superseded.  

If you have a battery bank larger than that recommended by the manufacturer, both the Battery bank and the Charger life will be shortened for two reasons.

The first is because the AL110 and AL310 (both low power 10amp mains 230v chargers) will support a habitation battery bank no greater than about 90Ah. Remember that these units, like AL320, charges BOTH the Habitation battery and the Starter Battery so it already on the limit

Secondly the unit controls all charge to the habitation battery whether from Solar (inbuilt Solar reg), Alternator or mains charger. If a second, big, battery is fitted this increases the current through the unit from the Alternator, which the Spade connector type of plugs struggle to handle, resulting in a burnt front connector and PCB. 

See the photo below showing a badly burnt White Habitation battery connector and Red Starter battery connector just starting to fail. This unit only had a single habitation battery fitted, but the battery was poor.

Two big batteries + the Fridge 12v power can draw upto 40amps from the Alternator, all of which goes in through the bottom left Red socket. 

This current is then split, the Fridge 14amps going out the Green Socket to the Fridge and the Habitation charge going out through the habitation White socket.


Excess current may also be passed through the unit if the Habitation battery is allowed to become poor, as the Alternator can be working harder for longer, so again over powering the front connectors. The damage shown in the photo above is becoming more common and it isn't just the connectors that are burnt, but the circuit board behind. Usually rendering the unit scrap.

The later 20amp units have uprated RAST5 front connectors which will take a little more current, but the practical restriction is still no more than a 160Ah TOTAL battery bank, which remember includes the Starter battery which it also looks after. We would suggest a habitation battery bank of 140Ah is the practical limit for the later chargers and 90Ah for the early AL320's and all the AL310's.

The AL120 restrictions are as per the AL320.

If you upgrade from an old unit to a late unit, the connector plugs in the cable harness will also require upgrading. 


The AL310/AL320 all have an inbuilt Solar regulator that will handle a 100watt Solar Panel. Just plug the Panel cabling into the centre front 2 pin connector. MAKE SURE THE POLARITY IS CORRECT OR YOU WILL DAMAGE THE UNIT. The polarity is marked on the front of the Arsilicii box.

Note the later RAST5 connectors on the latest unit above.


That is not just our advice. Arcillisi were asked their view on long term battery charging, here is the reply from ArSilicii Technical :

"If you have the motorhome parked, we suggest to not connect the 220V continuously".

We suggest you connect it to the mains supply once every 3 weeks for about 2 - 3 days. See our "EHU Full Time - Yes or No" page for the reasons why.


For more information on how to contact us use the Contact Us page.




Pictures and Guidance on the various Arsilicii systems : 

Arsilicii AL120 operation and wiring notes.pdf Arsilicii AL120 operation and wiring notes.pdf
Size : 161.954 Kb
Type : pdf
Arsilicii AL320 architecture instructions.pdf Arsilicii AL320 architecture instructions.pdf
Size : 872.27 Kb
Type : pdf

A Arsillici V3 Fuse Board.