... years Hardness scales: HL, HRC, HRB, HV, HB, HS RS232 Interface SV-T201 Ultrasonic Thickness Gauge Handy, precise, excellent EMC performanceInstrument ... Time: about 150 hours(with backlight off)Data Memory: 200 readingsPower off: Auto power off if not working for 2 minutes, ... energy monitoring.Able to communicate with the PC via RS232 interface, and connect to the micro printer for report printing ...