DDSY6789 single phase prepayment electric energy meter, LED display, long terminal block ... phase AC active electric energy.2. Power-down, the table for more than 10 years date retention ... , can produce sound and light alarm and power failure alarm, timely prompts the user enough ... meter maximum current of 1.5-2 times. 7. Unique anti-static mount IC design, can withstand 8KV ESD attack. Power meter ...