... -wire connection; regardless positive and negative class, all in one main line System specificationsHost Capacity 60pcs/80pcs/100pcs Maximum communicate ... or 110V,60HZStatic power consumption 25W Workin a row main line voltage 19V±1V ambient temperature 0-40°C ... report the call number synchronously.2. Display in English: LCD displayer, Main menu operated in English, show operation process, time, calls ...