Masterlink BTM-III. 12/24v DC. A Mastervolt battery monitoring panel brings an end to nasty surprises, like a sudden shortage of battery power. The Masterlink BTM-III battery monitor provides an accurate indication of the current, amperage, remaining time and remaining capacity of battery bank 1, and the current and estimated capacity of battery banks 2 and 3. The built-in microprocessor calculates the remaining capacity and stores historic data. The Masterlink BTM-3 includes ten languages English, French, German, Spanish, Italian, Dutch, Norwegian, Danish, Swedish and Finnish. 12/24v DC. A Mastervolt battery monitoring panel brings an end to nasty surprises, like a sudden sho The Masterlink BTM-III battery monitor provides an accurate indication of the current, amperage, rem