Simpson 270-5, Инструкция по эксплуатации

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Turn off power to the circuit and wait until the meter indicates zero before discon-
necting the test leads.
4.11 Output Voltage Measurement
Measuring the AC component of an Output Voltage where both AC and DC volt-
age levels exist is sometimes necessary. This occurs primarily in amplifier cir-
cuits. The 270 has a 0.1 mfd, 400 volt capacitor in series with the OUTPUT jack.
The capacitor blocks the DC component of the current in the test circuit, but
allows the AC or desired component to pass on to the indicating instrument
circuit. The blocking capacitor may alter the AC response at low frequencies but
is usually ignored at audio frequencies (Figure 4-4).
Do not connect the OUTPUT jack to a circuit in which the DC voltage component
exceeds 350V.
Before proceeding with the following steps, review the Safety Precautions in
Paragraph 4.1.
a.
Set the function switch at AC (Figure 4-5).
b. Plug the black test lead into the - COMMON jack and the red test lead into the
OUTPUT jack.
c. Set the range switch at one of the range positions marked 2.5V, 10V, 50V, or
250V.
!
Figure 4-4. Frequency Response Output Ranges
PERCENT RELA
TIVE ERR
O
R
+10
+8
+6
+4
+2
0
-2
-4
-6
-8
-10
10Hz 100Hz 1KHz
10KHz
100KHz
FREQUENCY
2.5 VAC RANGE
10VAC RANGE
50 VAC RANGE
250 VAC RANGE
OUTPUT RANGES
1MHz