ModeHold25%Range7. Main Function Operation7.1 Measurement/Output SwitchADT209 and ADT210 provide the following functions:Voltage Measurement◆Switch measure◆Current output◆Simulate transmitter output◆Current measurement◆Loop transmitter current measurement◆In the measurement/output interface, you can press to switch through above functions.7.2 Backlight Brightness AdjustmentIn any non-input screen, you can press and hold to adjust backlight brightness(3-level brightness adjustment).7.3 Keypad lockIn the measurement/output interface, you can press and hold to lock/unlock the keypad.7.4 Voltage MeasurementVoltage measurement interface can simultaneously display , youvoltage measurement value and percentage of rangecan press and hold to switch the current range, the voltage measurement has 3 ranges: 0 ~ 30V (0% ~ 100%) [default]◆ 1V ~ 5V (0% ~ 100%)◆ 0 ~ 10V (0% ~ 100%)◆6