EXTECH MG325 [7/18] Operating instructions

7 MG325-en-GB_v1.1 3/16

6. OperatingInstructions

WARNING: Risk of electrocution. High-voltage circuits, both AC and DC, are very dangerous and should be

measured with great care.

1. ALWAYS turn the function switch to the OFF position when the meter is not in use.

2. If “>” appears in the display during a measurement, the value exceeds the maximum range of

the meter.

6.1 Display Backlight

Press and hold the button to switch the backlight on or off. Excessive use of the backlight will

cause the batteries to drain quicker.

6.2 Data Hold

The Data Hold function freezes the reading in the display. To freeze or unfreeze the reading, press

H (Data Hold) key. The H icon is shown when data hold is active. This mode is only available for the

AC/DC Voltage, Resistance, and Capacitance modes.

6.3 Low Battery Indication

When the icon appears in the display, the battery must be replaced. See the Maintenance

section for details on battery and fuse replacement.

6.4 DC VOLTAGE MEASUREMENTS

CAUTION:

When the measured voltage is > 42VDC or 600VAC the meter flashes the warning icon on the upper left.

Do not measure DC voltages if a motor on the circuit is being switched ON or OFF. Large voltage surges may

occur that can damage the meter.

1. Set the function switch to the position.

2. Insert the black test lead banana plug into the negative EARTH jack

(6).

Insert the red test lead banana plug into the positive V jack (7).

3. Touch the black test probe tip to the negative side of the circuit.

Touch the red test probe tip to the positive side of the circuit.

4. Read the Voltage in the main display and in the lower bargraph.

5. Press the

button to store the reading.

6. Short press the H (Hold) button to freeze (H icon displayed) or

unfreeze (no H icon displayed) the displayed reading.

7. Note that the Auto Power OFF function activates after 10 minutes of

inactivity. The meter will audibly beep just prior to shutting off.

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