Sealey TM103 - Manual (Page 5)

4. 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
reading. This is normal and is caused by the high-input sensitivity. The reading will stabilise and give a proper measurement when
connected to a circuit.
4.1. MODE BUTTON
4.1.1. To select Diode / Continuity, DC / AC Hz / %Duty.
4.2. RANGE BUTTON
When the meter is first turned on, it automatically goes into Auto Ranging. This automatically selects the best range for the
measurements being made and is generally the best mode for most measurements. For measurement situations requiring
that a range be manually selected, perform the following:
4.2.1. Press the RANGE button. The “AUTO” display indicator will turn off.
4.2.2. Press the RANGE button to step through the available ranges until you select the range you want.
4.2.2. Press and hold the RANGE button for 2 seconds to exit the Manual Ranging mode and return to Auto Ranging.
4.3. DATA HOLD BUTTON
The Data Hold function allows the meter to “freeze” a measurement for later reference.
4.3.1. Press the DATA HOLD button to “freeze” the reading on the indicator. The indicator “HOLD” will be appear in the display.
4.3.2. Press the DATA HOLD button to return to normal operation.
4.4. RELATIVE BUTTON
The relative measurement feature allows you to make measurements relative to a stored reference value. A reference
voltage, current, etc. can be stored and measurements made in comparison to that value. The displayed value is the
difference between the reference value and the measured value.
4.4.1. Perform any measurement as described in the operating instructions.
4.4.2. Press the RELATIVE button to store the reading in the display and the “REL” indicator will appear on the display.
4.4.3. The display will now indicate the difference between the stored value and the measured value.
4.4.4. Press the RELATIVE button to return to normal operation.
4.5. 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.
4.5.1. Set the function switch to the V AC / DC position, press the Mode button to select DC.
4.5.2. Insert the black test lead banana plug into the negative (COM) jack. Insert the red test lead banana
plug into the positive (V) jack.
4.5.3. 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.
4.5.4. Read the voltage in the display. AutoRanging will select the correct range, or manually select the
desired range (see 4.2) to obtain a higher resolution reading. The display will indicate the proper
decimal point and value. If the polarity is reversed, the display will show (-) minus before the value.
.
4.6. AC VOLTAGE MEASUREMENTS

WARNING! Risk of Electrocution. The probe tips may not be long enough to contact the live parts inside some 240V
outlets for appliances because the contacts are recessed deep in the outlets.
As a result, the reading may show 0 volts when the outlet actually has voltage on it.
Make sure the probe tips are touching the metal contacts inside the outlet before assuming that
no voltage is present.
CAUTION: Do not measure AC voltages if a motor on the circuit is being switched ON or OFF.
Large voltage surges may occur that can damage the meter.
4.6.1. Set the function switch to the V AC / DC position. press the Mode button to select AC.
4.6.2. Insert the black test lead banana plug into the negative (COM) jack.
Insert red test lead banana plug into the positive (V) jack.
4.6.3. 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.
4.6.4. Read the voltage in the display. AutoRanging will select the correct range, or manually select the
desired range (see 4.2) to obtain a higher resolution reading. The display will indicate the proper
decimal point and value. If the polarity is reversed, the display will show (-) minus before the value.
TM103 Issue No: 2(I) - 18/06/14 © Jack Sealey limited Original Language Version