A new EMC 2004/108/EC Directive became effective on 20th July, 2007.
The EMC Directive requires that products must not generate unwanted electromagnetic pollution, or interference, and that products must be immune to a reasonable amount of interference.
Cable glands, which are not considered to fall under the scope of the EMC as they are neither capable of emitting electromagnetic interference nor being susceptible to it, may be used to contribute to the electromagnetic compatibility of installations. Several industry studies have been conducted as to the effect of cable terminations in systems that are required to provide a specified degree of EMC protection.
CMP Products has carried out 3 Metre Class B Radiated Emission Measurement tests in accordance with EN 55022 to verify the performance of cable sealing glands that are terminated on screened and armoured cables using a 360º termination of the metallic cable sheath. The typical results of these CNE measurement tests are shown below, with the noise reduction performance levels seen to be significantly improved in figure ii when the cable has been correctly terminated in the CMP cable gland. Figure i. shows that when the cable has not been terminated in such cable gland, the noise levels recorded are far higher than the acceptable Class B noise floor shown.
Comparison Noise Emission Measurement Test - CMP Armoured Cable Gland. Cable Without Cable Gland Terminated & Sealed.
Comparison Noise Emission Measurement Test - CMP Armoured Cable Gland. Cable With Cable Gland Terminated & Sealed
For further information, reference should also be made to applicable installation standards, e.g. IEC 61000-5-2: - Electromagnetic compatibility (EMC). Installation and mitigation guidelines - Earthing and cabling.