Decoupling Networks (CDNs) for IEC / EN 61000-4-6 Testing
Com-Power CDNs are designed and constructed to comply with standard EN 61000-4-6 Immunity to Conducted Disturbances Induced by Radio Frequency Fields (also IEC-1000-4-6 and CISPR 16). Electronic products can be susceptible to interference from nearby transmitters due to signal coupling to external I/O cables of the product's This is especially true for products with long external power, communication and interface cables. The level of interference that product must be able withstand is defined in the standard. A CDN is used to couple the disturbing signals to the product I/O cables. These levels are are injected into the CDN using a suitable power amplifier (similar to Com-Power ACS-181 or ACS-230) and an RF signal generator.
The CDN consists of circuits for coupling and decoupling injected RF signals. The the coupling circuit injects the disturbing signal into the cables under test.. The decoupling circuit prevents the injected signal from reaching the auxiliary equipment (AE) connected to the EUT.
Each CDN is specific to the type of cable and corresponding connector. Com-Power offers an extensive range of CDNs to test most standard cable types. You may require additional CDNs to decouple or isolate all other cables that are not subjected to the test, but are connected to the EUT. EN 61000-4-6 standard requires that an appropriate CDN be connected in this situation.
Each CDN is calibrated to meet the performance requirement given in IEC-61000-4-6 standard prior to shipment. The impedance data and certificate of calibration is shipped with each unit.
Below is a brief description of each CDN type available from Com-Power:
series CDNs for power line cables
Coupling Decoupling Networks are recommenced for all power supplies connections. The disturbing signals are to coupled to each conductor in the supply lines according to EN 61000-4-6 standard.
The standard M series CDNs have a current rating of 25 Amps. Com-Power CDNs are available for power supplies from 1 to 5 conductors. These CDNs cover the frequency range of 150 kHz - 230 MHz.
series CDNs for shielded coax cables
series CDNs are for coupling disturbing signals on to 50
Ohm (CDN-C50) and 75 Ohm (CDN-C75) shielded coax cables. These
CDN have BNC connectors for EUT and AE connections.
series CDNs for unshielded signal cables
series CDNs are for unshielded cables with two, four and eight
conductors carrying low current. AF series CDNs are supplied with
S Series CDNs for shielded signal cables
series CDNs are for shielded cables with single or multiple
conductors. These CDNs are supplied with professional audio (RCA),
D type and Centronics connectors.
series CDNs for unshielded balanced pairs
series CDNs are for cables with unshielded balanced conductor
pairs typically found in ISDN, DSL and Ethernet data transfer
Calibration accessories for The CDN
The RF disturbance levels that EUT has to be subjected to (1 V/m, 3 V/m, 10 V/m RMS) is specified in EN-61000-4-6. The conducted immunity setup must be calibrated make sure the proper levels are being generated during the compliance test. This setup includes signal generator, power amplifier, directional coupler, CDN, attenuator, cables, etc. In order determine disturbance levels being generated the following additional accessories are needed. These adapters are made according to the requirements specified in EN-61000-4-6.
- One set of shorting adapters for each type of CDN - Part# ADA-xxx ( xxx = model number)
- Two 150 Ohm to 50 Ohm adapter - ADA-515
- 50 Ohm terminator - Part # - TEP -050