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1 6 452 A Liqu id di electric tes t fix ture T erminal connector : 4- T er minal P air , SM A Dimensions ( appr o x.): 8 5 (H) x 85 ( W ) x 37 (D ) [mm ] Wei gh t (ap pr ox .): 14 0 0 g Measur ement accuracy: A + B + C […

16451B Dielectric test fixture continued

Compensation and measurement: There are three measurement methods for the

16451B. They are the Contacting Electrode Method (used with 16451B’s rigid metal

electrode, without any electrodes on the material under test), the Contacting Electrode

Method (used with thin film electrodes made on the material under test), and the Non-

Contacting Electrode (Air Gap method). Select the suitable measurement method and

the suitable electrode for the material under test according to the following table.

Summary of measurement method

Open and short compensations are recommended in combination with the cable length

compensation before measurement. When measuring above 5 MHz with the E4990A,

load compensation is also recommended. First, set the instrument’s cable length

compensation function to 1 m. Then, open and short compensation is performed by

using the furnished electrode attachment. Load compensation is performed, by prepar-

ing a working standard. After performing open, short and load compensations, the MUT

is sandwiched by the parallel electrodes and the capacitance is measured. Relative

permittivity is calculated from the measured capacitance in the following manner:

× C

εr�=

π × (—)

× ε

εr� : Relative permittivity

: Capacitance (measurement data)

: 8.854 × 10

–12

[F/m]

: Average thickness of test material

d : Diameter of guarded electrode

Up to 120 MHz (4-Terminal Pair): Material continued

Measurement

method

Contacting electrode method (used with

rigid metal electrode)

Contacting electrode method (used

with thin film electrode)

Non-contacting electrode method

Accuracy Low > High

Operation Simple > Complex

Applicable

materials

Thick, solid and smooth materials Materials on which thin film can

be applied without changing its

characteristics

Thick, and soft materials Rough

materials also

25 | Keysight | Accessories Catalog for Impedance Measurements - Catalog

16452A Liquid dielectric test fixture

Terminal connector: 4-Terminal Pair, SMA

Dimensions (approx.): 8

5 (H) x 85 (W) x 37 (D) [mm]

Weight (approx.): 1400 g

Measurement accuracy: A + B + C [%]

Up to 120 MHz (4-Terminal Pair): Material continued

Description: This test fixture provides accurate dielectric constant and impedance

measurements of liquid materials. The 16452A employs the parallel plate method,

which sandwiches the liquid material between two electrodes to form a capacitor.

A LCR meter or an impedance analyzer is then used to measure the capacitance

created from the fixture.

Applicable instruments: E4980A/AL, E4990A

Frequency: 20 Hz to 30 MHz

Operating temperature: –20 to 125°C

Maximum voltage: 30 Vrms

Material capacity: Required sample liquid capacity depends on the gap of the electrodes.

Furnished accessories:

Requires the following interface cables to connect to a measurement instrument. Select

accordingly to the required temperature conditions.

* Four BNC(m) to BNC(m) adapters (P/N 1250-0216) are needed to connect

the 16048G/H and 16452A.

Error B [%]

Error A [%]

Error C [%] = Measurement Error of Instrument

LCR meter with 16452A

(A)

(H)

(B)

(I)

(C)

(F)

(E)

(D)

(G)

Gap of electrodes 0.3 mm 0.5 mm 1 mm 2 mm

Air capacitance 34.9 pF ±25% 21.2 pF ±15% 10.9 pF ±10% 5.5 pF ±10%

Sample liquid capacity 3.4 ml 3.8 ml 4.8 ml 6.8 ml

Applicable frequency 20 Hz – 30 MHz

Temperature Model# or P/N Cable length (approx.)

0 to 55°C 16048A 0.94 m

–20 to 150°C 16048G* for E4990A only 1 m

–20 to 150°C 16048H* for E4990A only 2 m

Description P/N Qty.

Shorting plate 16092-08010 1 E

O-ring for liquid outlet 0905-1277 1 D

Spacer (1.3 mm thickness) 16452-00601 1 F

Spacer (1.5 mm thickness) 16452-00602 1 F

Spacer (2.0 mm thickness) 16452-00603 1 F

Spacer (3.0 mm thickness) 16452-00604 1 F

Lid of liquid outlet 16452-24002 1 G

SMA-BNC adapter 1250-1200 4 H

Waterproof cap for BNC connector 1252-5821 4 I

Carrying case 16452-60111 1 –

Operation and service manual 16452-90020 1 –

Angle iron of stand body for fixture stand 16452-01201 2 –

Screw of stand body or fixture stand 0515-0914 4 C

Screw for fixture stand 0515-0914 4 –

Stand foot

16452-00611

1 –

Electrode (high and low) NA 2 A.B

26 | Keysight | Accessories Catalog for Impedance Measurements - Catalog

Up to 120 MHz (4-Terminal Pair): Material continued

Compensation and measurement: Short compensation is recommended

in combination with the cable length compensation before measurement.

First, set the instrument’s cable length compensation function to 1 m. Then,

short compensation is performed by using the furnished shorting plate. Open

compensation is not performed, but its values are used in the dielectric constant

equation as shown below:

Cp 1

= α (

– j

_______

)

Co ω CoRp

α : Correction coefficient

: Relative dielectric constant

Cp : Liquid capacitance (measurement data)

Co : Air capacitance (measurement data) or open compensation data

Rp : Equivalent parallel resistance (measurement data)

ω : Angular frequency (ω= 2πf)

The following figures below show how compensation and measurement is

performed.

Note: The 16452A is not capable of measuring salt or ionic solutions or other

liquids with bulk conductivity due to the electrode polarization phenomenon.

Keysight is not responsible for any damage (e.g., corrosion, smear) to the 16452A

caused by the reaction between the liquid under test and the 16452A.

Test fixture overview

Short compensation

Method of connection

Pouring the liquid into the fixture

Fixture materials

Electrode: Ni plated Cobal

(Fe 54%, Co 17%, Ni 29%)

Insulator: Alumina (Al

)

O-ring: Viton (Fluro rubber)

16452A Liquid dielectric test fixture continued

27 | Keysight | Accessories Catalog for Impedance Measurements - Catalog