Simpson 260-6LPM, Инструкция по эксплуатации

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f. Read the current in mA on the black DC scale marked 0-50 for the 0.5 mA
ranges, divide the reading by 100 and 10, respectively. Read the 50 mA
range directly. Multiply the reading on the 500 mA range by 10.
g. Turn power off, disconnect test leads and return the range switch to the OFF/
TRANSIT position.
4.10.3 Measuring Direct Current: 0-5A
a. Plug the black test lead into the -5A jack and the red test lead into the +5A
jack.
b. Set the range switch to the 5A position (dual position with 5 mA).
c. With power off, open the circuit in which the current is being measured. Con-
nect the Instrument in series with the circuit. Connect the red test lead to the
positive side and the black test lead to the negative side.
d. Turn on power in the circuit under test.
NOTE: The function switch has no effect on polarity for the 5A range.
e. Read current directly on the black DC scale. Use the 0-50 figures; divide by
10 to read amperes.
f. Turn power off and disconnect test leads. Return the range switch to the
OFF/TRANSIT position.
4.11 Resistance Measurement
Before making resistance measurements, remove all power to the circuit under
test. Discharge all capacitors.
The 260’s have six resistance ranges. Two are low power ohms and the other four
are conventional ohm ranges powered by two batteries. The low power ohms
ranges are used for accurate and safe measurements of resistance in semicon-
ductors and integrated circuits. The low open-circuit voltage of 100 mV assures
that the circuit being measured will not be damaged or have its resistance affected
by conducting diodes. Depending on the range selected, the open-circuit voltage
for the conventional ohms ranges is 1.5V or 9V.
A single OHMS ADJ control is provided for all the resistance ranges. This control
compensates for variations in battery voltage and allows the user to zero the In-
strument prior to measuring resistance.
4.11.1 Measuring Resistance: Low Power Ohms Ranges
a. Turn the range switch to the desired resistance range marked in blue. Turn
the function switch to either the -DC or +DC position.
b. Plug the black test lead into the -COMMON jack and the red test lead into the
+jack.
c. With the test leads separated, rotate the OHMS ADJ control to set the Instru-
ment pointer at infinity ( ) on the blue low power ohms arc. If the pointer
cannot be adjusted to infinity ( ), replace the 1.5V battery.
d. Connect the test leads to the circuit whose resistance is to be measured.
Read the resistance on the blue arc and multiply it by the factor indicated on
the range switch.
e. Disconnect the test leads and return the range switch to the OFF/TRANSIT
position.
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