Ac Effective Common-Mode Rejection Test; Dc Voltmeter Input Resistance Test; Ac Voltmeter Input Impedance Test - HP 3465B Operating And Service Manual

Section V PERFORMANCE TESTS Model 3465B
AC CALIBRATOR
hp 745A*
□ □ D OD
(SQ I I I I I I I I
cm I I I I I m
O
OR EQUIVALENT
ELECTRONIC COUNTER
hp 5300A*
o c
o o o
I.OuF
—
I
DIGITAL MULTIMETER
hp 3465
1
jjjjjj jjjjjjj
o ,
o
Figure 5-5. AC Normal-Mode Rejection Test.
5-21. AC Effective Common-Mode Rejection Test.
b. Set the Multi
5-22. An AC Calibrator, an Electronic Counter and a 1 kf2
± 1% resistor are required for this test.
a. Connect a 1 kfi resistor between the Vf2 and COM
terminals.
b. Set the Multimeter function to DCV ( V) and
range to 20 mV. Note the Multimeter indication.
c. Connect the AC Calibrator to the Multimeter as
shown in Figure 5-6.
d. Using the Electronic Counter as a monitor, set the
AC Calibrator frequency to 60 Hz ± 0.1% (50 Hz ± 0.1% if
operating Multimeter from a 50 Hz source).
e. Adjust the Calibrator output to 7.07 V rms (10 V
peak).
f. Note the Multimeter indication. The reading should
not vary more than 10 microvolts from the reading noted in
Step b verifying an ac common-mode rejection of greater
than 120 dB.
5-23. DC Voltmeter input Resistance Test.
5-24. A DC Standard and a 10 Mf2 ± 0.1% resistor (or
equivalent) are required for this test,
a. Connect the Multimeter, DC Standard and resistor as
shown in Figure 5-7.
meter function to DCV ( V) and
range to 20 V.
c. Cormect a jumper across the 10 MJ2 resistor and
adjust the DC Standard to provide a Multimeter display of
+ 10.000.
d. Remove the jumper from the 10 Mf2 resistor. The
Multimeter display should indicate 4.975 to 5.025 veri
fying an input resistance of 10 Mf2 ± 1% on the 20 V
through 1000 V ranges.
e. Change the DC Standard output to 0 V and change
the Multimeter range to 2 V.
f. Connect a jumper across the 10 Mf2 resistor and
adjust the DC Standard to provide a Multimeter display of
+ 1.0000.
g. Remove the jumper from the 10 Mf2 resistor. The
Multimeter display should indicate .9990 or greater veri
fying an input resistance of > 10'° on the 20 mV through
2 V ranges.
5-25. AC Voltmeter Input Impedance Test.
5-26. An AC Calibrator and a 1 Mfl ±0.1% resistor (or
equivalent) are required for this test.
a. Connect the AC Calibrator and a 1 Mfl resistor as
shown in Figure 5-8. Connect a jumper across the resistor.
AC CALIBRATOR
hp 745A»
D □
0 DD
o
in
rm I I I I I □□
O
*0R EQUIVALENT
ELECTRONIC COUNTER
hp 5300A*
DIGITAL MULTIMETER
hp 3465
o c
c
go
o o o
3465-B'4269
Figure 5-6. AC Effective Common-Mode Rejection Test.
5-6