NF ZM2371, Instruction Manual

Page: 228 / 255

8.7 Performance Testing
8-5 ZM2371/ZM2372
8.7.3 Voltage Monitor Accuracy
Connection: H
CUR
and H
POT
terminals together → AC voltmeter input (– terminal)
L
CUR
and L
POT
terminals together → AC voltmeter input (+ terminal)
For the connection, use kelvin test lead or coaxial cable.
To use the coaxial cable, connect 4 shields all together.
The cable length should be approx 1m or less in total length.
Kelvin clip H terminal + terminal
AC voltmeter
test lead, etc. L terminal – terminal
For the multimeter, which is activated by AC power, if large
capacitance to earth is connected to L terminal, LCR meter gets
unstable and correct measurement may not be done. Therefore, we
recommend you to c/– inversely. If it is possible to make
correct measurement, no need to connect inversely.
Setting: After initializing the setting, set the measurement frequency and
measurement signal level according to the contents in table stated below.
Press the
_ AUX DISP _
key to display the auxiliary display selection menu,
and switch the auxiliary display into current monitor value and Voltage
monitor value.
Measurement:
Measure the output voltage under each condition with the AC voltmeter.
Evaluation: If the values of voltage monitor are within the specification range in table
for the specified values of voltmeter, it is normal.
Frequency
120Hz 1kHz 10kHz 100kHz
Spec. :
±
(2% + 2mVrms) Spec. :
±
(3.5% + 2mVrms)
Measurement
signal level
0.1Vrms
Monitor
Spec.
±
4.0
Difference:
mVrms
Monitor
Spec.
±
5.5
Difference:
mVrms
Voltmeter Voltmeter
1Vrms
Monitor
Spec.
±
22
Difference:
mVrms
Monitor
Spec.
±
37
Difference:
mVrms
Voltmeter Voltmeter
5Vrms
Monitor
Spec.
±
102
Difference:
mVrms
Monitor
Spec.
±
177
Difference:
mVrms
Voltmeter Voltmeter