General Tools and Instruments CMR35 - Manual (Page 9)

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WARNING
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To avoid exposing yourself to a harmful or a fatal voltage and damaging the
transmitter, make sure that the potential you are attempting to measure is less
than 600VAC.
As in current measurement mode, the CMR35T automatically chooses the narrowest
measurement range that includes the tested value. The four available full-scale ranges
are 0 to 4V, 0 to 40V, 0 to 400V, and 0 to 600V.
Read the measured value once it stabilizes. When you have finished making measure -
ments, move the function switch to the OFF position.
MEASURING RESISTANCE
To measure the resistance between two points of an electrical or electronic circuit, first
make sure that the circuit you are measuring is not carrying any current. Then move the
function switch to the Ω /
position. The display should then read “O.L”, with
the symbol “MΩ” at the upper right.
Plug the rubber-covered end of the black probe into the COM jack of the transmitter and
the rubber-covered end of the red probe into the
jack. Then touch the metal ends of
the black and red probes to the points between which you wish to measure the
resistance. To avoid affecting the measurement, make sure not to touch the metal tip of
either probe.
The CMR35T automatically chooses the narrowest measurement range that includes the
tested resistance value. The six available full-scale ranges are 0 to 400Ω, 0 to 4kΩ, 0 to
40kΩ, 0 to 400kΩ, 0 to 4MΩ, and 0 to 40MΩ
Read the measured value once it stabilizes. When you have finished making resistance
measurements, move the function switch to the OFF position.
TESTING DIODES AND CHECKING CONTINUITY
To test the integrity of a diode, move the function switch to the Ω /
position. Press the REL./SEL. button until the
symbol appears in the top row of the
display, as shown in Fig. 2. Plug the rubber-covered end of the black probe into the COM
jack of the transmitter and the rubber-covered end of the red probe into the
jack.
The CMR35T supports both forward-bias and reverse-bias diode testing. To perform a
forward-bias test, first make sure that the diode you are measuring is not carrying any
current. Then touch the tip of the red probe to the diode’s anode (+ lead) and the tip of
the black probe to the diode’s cathode (- lead), as shown in part A of the figure on
page 10.
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CMR35 Manual FINAL4_020911:awb 2/9/11 11:54 AM Page 9