"1 Phase & 3 Phase systems -11 to 300V(L-N), 19 to 519V(L-L) measurement -Accuracy of ± 0.5% of voltage, ±1% of current, ±0.1Hz of frequency -±0.5% for RPM & ±1% for run hour -3 rows 3 digits LCD display with back light -Panel mount -Supply voltage of 230 V AC ± 20%, 110 V AC ± 20%"