... Resolution:0.001ohm,0.05mA 4.RS232 ETCR2100C+ Clamp on ground resistance tester . Introduction ETCR new Clamp Earth Resistance ... tone, Alarm Symbol Flashing, Press AL key to turn on, turn off Alarm or set Alarm Threshold.Interference Signal ... .minisite.productShow(); oProductShow.init( { 'aImgSrc': aBigImageSrc } ); } )(); ETCR2100C+ Clamp on ground resistance tester ----ISO,CE,OEM,ODM.RS232 Interface