Extech Instruments 470 User Manual

Page 8

V5.0 5/04

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 “OL” appears in the display during a measurement, the value

exceeds the range you have selected. Change to a higher range.

NOTE:: On some low AC and DC voltage ranges, with the test

leads not connected to a device, the display may show a
random, changing reading. This response is normal and is
caused by the high-input sensitivity. The reading will stabilize
and give a proper measurement when connected to a circuit.

DC VOLTAGE MEASUREMENTS

CAUTION: 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 green

V position.

2. Press the SELECT button to indicate

“DC” on the display.

3. Insert the black test lead banana

plug into the negative COM jack.
Insert the red test lead banana plug
into the positive V jack.

4. 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.

5. Read the voltage in the display.