meter counter: 1,ratio: 100:1,200:1,400:1 ... 1 3,Voltage:3.5v to 6.5v ISO9001: 2008 meter counterKey Technical IndexJD series Electronic Type Counter for Electric Energy ... minus 40 to plus 706, Working frequency: 6Hz7,Motor torque output: 30mNm8,Service life: greater than10yearsAnti-vibration and anti-impact property ... with GB/T17215Note: technical indexes for JDC3 double rate meter are identical.