LCX_UserManual_en_08_1.pdf - 第59页

Measurement setups R&S ® LCX Series 59 User Manual 1 179.2260.02 ─ 08 Figure 6-6: R&S LCX-Z1 1 BNC-to-BNC extension The extension also provides four BNC measurement ports for connecting a test fixture or establis…

100%1 / 265
Measurement setups
R&S
®
LCX Series
58User Manual 1179.2260.02 ─ 08
Figure 6-5: R&S
LCX-Z5 transformer test fixture and test cables
The test fixture comes with four test leads equipped with alligator clips, to contact the
primary and secondary circuits of the measurement sample. The BNC connectors on
the right and left outside are intended to contact the circuit with the higher number of
windings. The two BNC connectors in the middle are intended for the circuit with lower
number of windings.
As an alternative, it is possible to install a user-specific test setup at the BNC connec-
tors directly.
6.1.6 BNC-to-BNC extension
The R&S LCX-Z11 BNC-to-BNC extension (1m) enables you to place the test setup in
the distance of 1 m from the site of the R&S LCX.
About test fixtures
Measurement setups
R&S
®
LCX Series
59User Manual 1179.2260.02 ─ 08
Figure 6-6: R&S
LCX-Z11 BNC-to-BNC extension
The extension also provides four BNC measurement ports for connecting a test fixture
or establish user-specific connection.
When you use the R&S LCX-Z11 BNC-to-BNC extension, you must set the cable
length to 1 m in the measurement settings for cable length compensation, see Sec-
tion 8.6.1, "Measurement parameter settings", on page 78.
How to: see "Connecting a test fixture with the BNC-to-BNC extension" on page 26
6.2 Configuring the test signal
The accuracy of the measured impedance depends mainly on the test frequency and
level. Therefore, each measurement requires that you specify the test signal to obtain
results under defined conditions.
In addition to the frequency and level settings, e.g. to measure at a certain working
point, you can define a measurement range. E.g., if you want to analyze the behavior
of a component over a certain range. For measurements of coils or capacitors you can
superimpose a current, or voltage bias, respectively.
We assume that you have set up the R&S LCX as described in Section 4.1.4, "Setting
up the R&S LCX", on page 19. For basic information on setting up a measurement,
including the test signal, see the example in "Basic measurement steps" on page 34.
For details on the setting parameters, see Section 8, "Instrument functions",
on page 70.
The following sections provide additional information to be considered for the specific
measurements.
Configuring the test signal
Measurement setups
R&S
®
LCX Series
60User Manual 1179.2260.02 ─ 08
Depending on a bias required for your measurement, see Section 6.3, "Configuring
BIAS", on page 61 on how to proceed.
Considerations for test signal configuration
●
Dependency of the selected impedance range and the low impedance mea-
surement setting
The impedance range depends on various settings, e..g., the range selection and
the setting of the "LowZ" state.
The following overview explains the corresponding setting (in quotes) for the impe-
dance in the expected range:
LowZ Mode > ON
– ≤10 Ω
"3 Ω": measures values from 0 Ω to ≈3 Ω
– >10 Ω
"10 Ω": measures all values but with limited accuracy
"30 Ω": measures values from 30 Ω up to infinity
LowZ Mode > OFF
– ≤100 Ω
"3 Ω": measures values from 0 Ω to ≈3 Ω
– >100 Ω
"100 Ω": measures all values but with limited accuracy
"300 Ω": measures values from 300 Ω up to infinity
To achieve best measurement results for the expected sample component, select
the range as close to these limits as possible.
Examples for LowZ Mode > OFF, based on the range settings 3 Ω, 10 Ω, 30 Ω,
100 Ω, 300 Ω, 1 kΩ, 3 kΩ, ...:
– 1.2 Ω DUT > select 3 Ω range
– 3.1 Ω DUT > select 10 Ω range
– 150 Ω DUT > select 100 Ω range
– 310 Ω DUT > select 300 Ω range
Auto range
The auto range function selects the range that fits best automatically.
●
Dependency of the mains frequency and the test signal frequency for high
impedances
Measuring high impedances with a signal frequency of ≈100 Hz or 120 Hz lead to
inaccurate readings as the mains frequency with usually 50 Hz / 60 Hz interferes
the test signal frequency.
For an example on how to configure the test signal parameters, see "Setting up the
test signal" on page 35.
Configuring the test signal