The Battery Master will not allow any charge to flow in the other direction, from the engine battery to the leisure battery.
This clever bit of wizardry addresses a common issue in modern motorhomes. The often ignored engine battery gets used a lot, but only gets charged when driving. Alarms drain the battery as does using the cigarette lighter.
How frustrating when you about to go on a trip and the engine battery is flat or after a week’s stay on a site, charging phones, listening to the radio etc. you discover, just as you are leaving, that the engine battery is flat. Even though you have been on a hookup!
The Battery Master keeps your engine battery safely topped up. Whenever you have surplus power from a hook-up, a solar panel or generator. It has a maximum charging current of 1.1 amps, which copes with these low-level losses from the starter battery.
We would not be without a Battery Master, we know that whenever we turn the key to start our motorhome our engine battery is always fully charged, even if we’ve left it for a month or two in a Welsh winter. Cold weather drains the battery and of course alarms are always sipping away slowly stealing all its power. But this matters not. If we are hooked up or the sun is on our solar panels, then any surplus power is used to keep the engine battery in tiptop condition.
It is fully waterproof and its British made and designed. This is the original and the best. There are cheaper copies of this product out there on eBay, but for me at least, with a product that is going to sit in my motorhome attached to my batteries; I did not fancy risking it with an inferior product.
The Battery Master is really easy to install and comes complete with instructions. It has three short leads which connect to the starter battery positive; the leisure battery positive; and to the vehicle earth (negative). The instructions are clear and comprehensive.