S46M5/9 High-current Coupling/Decoupling Network




The M5 configuration offers five substantial conductors capable of handling 50ampere circuits such as 3-phase, neutral, and earth. Special anti-resonance elements (See Reducing errors due to resonances in Radiated and Conducted EMC testing by R C Marshall, Paper 4F1, Zurich EMC Symposium, Feb. 18th-20th, 2003) allow the use of these conductors in M2, M3, and M4 mode without loss of accuracy, and they may also be linked in parallel pairs for two-wire 100 amp circuits.

In the M9 configuration one of the above five is split into 5 lower-current conductors for the control and sensing circuits that form part of high-current dc power supplies, for motor drives, or for energising the voltage measuring circuits of electricity meters.

This configuration also covers M6, M7 and M8 modes.

The network may be used for decoupling other cables to the EUT, and will support emission testing according to EN55022:1998.

S46M5/9 VCDN Specification

Injection/receiver circuit:

EUT rf common-mode impedance: 150W +- 20W from 0.15 to 26MHz.

150W + 60 - 45W from 26 to 80MHz.


Rf input/output: BNC socket. Maximum continuous input power 3 watts.

For E46xx only: VSWR < 2.5:1 referred to 50W.

User circuit:

This network may be configured as any of the networks for power cables described in EN61000-4-6 and for larger numbers of cores. As required in the standard the basic injection impedance of 150W in series with >30nF is applied by proportionately higher-impedance injection components connected to each core. Physically the CDN carries 4 major circuits of 4.65mm cross-section, together with 5 minor circuits of 0.6mm cross-section. The latter may be used in parallel as a ground wire for application as M1 to M5 inclusive, and used separately for M6 to M9.


Connectors: EUT and AE cables are connected to screw terminal blocks that can

accommodate 0.5 to 10mm flexible, stranded, or solid conductors.

Max volts: 440 Vac.

Max. current per core: At 30C ambient. Halve these figures if the fan is not used.

M5, M4: 50amps on 3 phase and neutral or 4 wires carrying dc.

M3: 100amps on 2 wires and 30amps on the third.

Parallel connecting cables should be used above 50amps.

M2: 100amps on 2 wires. Parallel connecting cables above 50amps.

M6-M9: The above current ratings apply to circuits 1 to 4.

Circuits 5 to 9 are rated at 6amps each.

Max. unbalanced current per cable and for M1 operation: 100mA peak or dc.

AE Filter capacitance: 22nF on each of the major circuits. 4n7 on each minor circuit.

All capacitors are safety rated.

Longitudinal conversion loss: typically > 40dB.


Cooling Fan: 12Vdc 1.3watts.


Dimensions (including projections): 280 x 180 x 105mm. Weight 1.6 Kilograms.


Accessories included: AC/DC Adaptor for fan supply (UK 13amp plug-mounted unless otherwise requested).

Comprehensive manual.

Accessories recommended: Calibration jig pair 46MZZ is essential.

46MZC Interface Adaptor between VCDN EUT interface and type N connector available for formal checking of CDN impedance. Ground plane 46GP and extension 46XP available. UKAS Certification available.

These items are components for use only in an appropriate laboratory environment and by suitably qualified and trained staff.

In the search for improved quality this specification is subject to change. Patents applied for. and Design rights reserved Richard Marshall Limited 2004