25Model UT58D: OPERATING MANUALSleep ModeTo preserve battery life, the Meter automatically turns offif you do not turn the rotary switch or press any button foraround 15 minutes. When the Meter is under sleep mode,it consumes 10μA current.To activate the Meter, press POWER for two times.Operation of Hold ModeWarningTo avoid possibility of electric shock, do not use Holdmode to determine if circuits are without power. TheHold mode will not capture unstable or noisy readings.