... rail installation 7 digits LCD display, 5+2 digits(99999.91kWh CT operation Class 1 accurancy MB421AC energy meter ... bottom, outlet from top), use CT connect operation, may select 27 CT ratio, the meter will read directly ... by CT rate. 4. 7 digits LCD display, 5+2 digits(99999.91kWh, Only when CT ratio 5:5A) ... display. It is choose by the CT ratio which is set. 5. Six LED instructions power supply state ...