• Frequency and Duty Cycle Measurement
Do not measure the frequency on high voltage (>1,000V) to avoid electrical shock hazard
and/or damage to the instrument.
The meter can measure frequency or duty cycle while making either an AC voltage or AC current measurement.
To measure frequency:
1. Set the rotary switch to the desired function (AC voltage or AC current) and press Hz/DUTY.
2. Read the displayed frequency of the AC signal.
3. To make a duty cycle measurement, press Hz/DUTY again.
4. Read the displayed duty cycle.
5. Set the rotary switch to the Hz range.
6. Connect the black and red test leads to the COM and Hz terminals respectively.
7. Connect the test leads in parallel to the circuit being measured. Do not touch any electrical conductors.
8. At frequency measurement status, press Hz/DUTY to enter the duty cycle measurement status. Press
again to return to the enter frequency measurement status.
9. Read the displayed value.
NOTE: In a noisy environment, use a shielded cable for measuring small signals.
• Temperature Measurement
To avoid electrical shock and/or damage to the instrument, do not apply more than 1,000VDC
or 1,000VAC RMS between the °C terminal and the COM terminal.
To avoid electrical shock, do not use this instrument when voltages at the measurement
surface exceed 60VDC or 24VAC rms.
To measure temperature:
1. Set the rotary switch to °C range. The LCD will show the current environment temperature.
2. Insert the "K" type thermocouples into the multi-function socket. Take care to observe the correct polarity.
3. Touch the object with the thermocouple probe for measurement.
4. Read the LCD.
• Current Measurement
To avoid damage to the meter or injury in case of a fuse blow, never attempt an in-circuit
current measurement where the open-circuit potential to earth is higher than 600V.
To avoid damage to the meter, check the meter's fuse before proceeding. Use the proper
terminals, function and range for your measurement. Never place the test leads in parallel with
a circuit or component when the leads are plugged into the current terminals.
The meter's ranges are 400.0µA, 40.00µA, 400.0mA, 4.000A and 10.00A.
To measure current:
1. Turn off the power of the measured circuit. Discharge all the high-voltage capacitors.
2. Set the rotary switch to the proper range.
3. Press SELECT to select the DCA or ACA measuring mode.
4. Connect the black test lead to the COM terminal and the red test lead to the mA terminal for a maximum of
400mA. For a maximum of 10A, move the red test lead to the 10A terminal.
5. Break the circuit path to be tested. Connect the black test lead to the more negative side of the break;
connect the red test lead to the more positive side of the break (reversing the leads will give a negative
reading, but will not damage the meter).
6. Turn on the power of the measured circuit and read the display. Be sure to note the measurement units at
the right side of the display (µA, mA or A). When only the figure "OL" is displayed, it indicates over range
situation and a higher range has to be selected.
DVM1100
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VELLEMAN