Measuring Currents; Measuring Resistance - Iso-Tech IDM 203 RMS Instruction Manual

1. Plug the black lead into the "COM" input terminal of the meter and the red lead into the "V-Ω- " input terminal.
2. Turn the function switch to the "Vd.c." or "Va.c." position.
3. Apply the probes to the source or load whose voltage is to be measured. The polarity of the red probe will be shown along
with the measurement. If the measurement is higher than the range of the meter or the range which has been set manually,
an audio signal is triggered and the most significant digit of the digital display flashes, while the three lower digits go to 0.

Measuring currents

1. Plug the black lead into the "COM" input terminal of the meter. To measure currents up to a maximum of 400 mA plug the
red lead into the "mA" input terminal and to measure currents up to a maximum of 10A plug it into the "A" input terminal.
(The meter can also measure and display currents of up to 20A but currents of this level must not be applied to it for more
than 30 seconds.)
2. Turn the rotary function switch to which ever range you require from "4mA" to "400mA" and set DC or AC with the function
button.
Note : If you do not know which range you require, start with the highest range and if need be repeat the measurement in
whichever lower range you then find to be required.
3. Connect the meter in series with the load from which a measurement is to be taken.

Measuring resistance

1. Plug the black lead into the "COM" input terminal and the red lead into the "V-Ω-Hz" input terminal.
(Note: The polarity of the red lead is positive.)
2. Turn the function switch to "Ω- " and use the function button to bring "Ω" up onto the display.
WARNING : To avoid the possibility of injury and to protect the meter from damage, make sure that the item from which
measurements are to be taken is not live.
3. Apply the probes to the item whose resistance is to be measured. To obtain the greatest possible accuracy with low resis-
tances, set the meter to the 400 Ω range, and before making a measurement short the probes together and press the
"REL" button. This will automatically correct for the resistance of the leads when subsequent measurements are made.
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