5
AutoCheck
TM
mode (model 257 & 255 only)
This innovative
AutoCheck
TM
feature automatically selects measurement function of DCV, ACV
or Resistance (
) based on the input via the test leads.
With no input, the meter displays “Auto” when it is ready.
With no voltage signal but a resistance below 10M
(nominal) is present, the meter displays the
resistance value. When the resistance is below “Audible Threshold”, the meter further gives a
continuity beep tone.
When a signal above the voltage threshold of 1V DC or AC up to the rated 1000V is present, the
meter displays the voltage value in appropriate DC or AC, whichever larger in peak magnitude.
Note:
*Range-Lock and Function-Lock Feature:
When a measurement reading is being displayed in
AutoCheck
TM
mode, press the
RANGE
or
SELECT
button momentarily 1 time can lock the range
or function it was in. Press the button momentarily repeatedly to step through the ranges or
functions.
*As Hazardous-Alert:
When making resistance measurements in AutoCheck
TM
mode, an
unexpected display of voltage readings alerts you that the object under test is being energized.
*Ghost-voltage Buster:
Ghost-voltages are unwanted stray signals coupled from adjacent hard
signals, which confuse common multimeter voltage measurements. Our AutoCheck
TM
mode
provides low (ramp-up) input impedance (approx. 2.5kΩ at low voltage) to drain ghost voltages
leaving mainly hard signal values on meter readings. It is an invaluable feature for precise
indication of hard signals, such as distinguishing between hot and open wires (to ground) in
electrical installation applications.
