Simpson 260-6LPM, Инструкция по эксплуатации

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4.9 Measuring Decibels
To read voltages in terms of decibels, use the decibel (dB) scale on the bottom of
the dial marked from -20 to +10. Read the dB scale by first following the instruc-
tions for measuring AC. When the range switch is set on the 2.5V position, read
the dB scale directly. The dB readings on the scale are referenced to zero dB
power level of 0.001W into 600V, or 0.775 VAC across 600 . For the 10V range,
read the dB scale and add +11 dB to the reading. For the 25V range, read the dB
scale and add +19 dB to the reading. On the 100V range, read the dB scale and
add +31 dB to the reading; on the 250V range, add +39 dB to the reading.
4.10 Direct Current Measurements
While the circuit is energized do not change the setting of the Function or Range
switches. Never disconnect the test leads.
Always turn the power off and discharge all the capacitors before resetting the
switches, or disconnecting the leads.
Always connect the Instrument in series with the ground side of the circuit under
measurement and never exceed the circuit to ground voltage (Table 1-1, item 7).
4.10.1 Measuring Direct Current: 0-50 μ A
a. Set the function switch to +DC.
b. Plug the black test lead into the –COMMON jack and the red test lead into the
+50
μ A/250V jack.
c. Set the range switch at the 25V (50 μ A) position.
d. Be sure the power is off in the circuit being measured and all capacitors are
discharged.
e. Open the circuit in which the current is to be measured. Connect the red test
lead at the positive side and the black test lead at the negative side.
f. Turn the power on and read the current on the black DC scale. Use the 0-50
figures to read directly in
μ A.
g. Turn the power off, disconnect test leads and return the range switch to the
OFF/TRANSIT position.
NOTE: In all direct current measurements make certain that the power to the cir-
cuit being tested has been turned off before connecting and disconnecting test
leads or restoring circuit continuity.
4.10.2 Measuring Direct Current: 0-0.5 through 0-500 mA
a. Set the function switch to +DC.
b. Plug the black test lead into the –COMMON jack and the red test lead into the
+jack.
c. Set the range switch at one of the four range positions marked 0.5 mA, 5 mA
or 500 mA.
d. Turn the power off, discharge all capacitors, and open the circuit in which the
current is being measured. Connect 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.
e. Turn on the power to the circuit under test.
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