General Tools and Instruments GT310 - Manual (Page 13)

Touch the test leads to two points in a circuit at different electric
potential. A minus sign (–) at the left of the reading indicates a
negative voltage.
To switch to Manual Ranging mode, press the Range button briefly
once to remove the AUTO indication from the top left of the display.
With two exceptions (the highest ranges), each subsequent brief press
of the button decreases the measurement sensitivity (increases the
full-scale measurement range) by a factor of 10 (one decimal place).
If the measured voltage is greater than the full-scale range, the
readout will be OL. To return to Auto ranging mode, press and hold
the Range button.
In AC or DC voltage measurement mode, the meter presents an input
impedance of >10M
Ω
to the circuit under test.
MEASURING RESISTANCE OR CAPACITANCE
Before measuring resistance or capacitance, be sure to remove power
from the circuit under test and to discharge any high-voltage
capacitors in it.
Turn the rotary dial to the
Ω
position. The unit M
Ω
will appear at the
right of the display. The word AUTO will appear at the top left,
indicating that the meter is in Autoranging mode.
To measure the resistance between two points of a circuit, touch the
test leads to those two points.
To measure the capacitance between two points of a circuit, press the
Select/0-9 button briefly three times to change the M
Ω
symbol to the
letter F. Then touch the test leads to the two points of interest.
To switch to Manual Ranging mode, press the Range button briefly
once to remove the AUTO indication from the top left of the display.
Each subsequent brief press of the button decreases the measurement
sensitivity (increases the full-scale measurement range) by a factor of
10 (one decimal place).
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