What is the difference between Category 5e network cabling that is CMP or CMR rated? What is the correct choice for my job?
All bulk format unshielded (UTP) network cable comes with different ratings, either 'CM', 'CMR' or 'CMP', as well as 'UL'. These UTP cable rating codes mean that the cables meets different UL-NEC requirements based mostly on cable jacket quality. Below is an explanation of the rating codes for each cable type.
UL - The National Electrical Code (NEC), published by the National Fire Protection Association (NFPA), details advisory safety considerations for electrical wiring. NEC Article 800 Communications Cables are manufactured to meet these different cable types. Most network cables have some sort of basic UL rating.
CMP (R-733, R-753) - The 'P' in CMP is for Plenum. Cables meeting type CMP requirements are suitable for installation in ducts and plenums without the use of conduit. These cables are designed for fire resistance and low-smoke and toxin producing characteristics. The 'P' in CMP is for Plenum.
CMR (R-731, R-751, R-756) - The 'R' in CRM is for 'Riser'. Riser type cables are engineered to prevent the spread of fire from floor to floor and are suitable for vertical shaft applications.
CM (R-732, R-752, R-757) - These are cables for general building wiring. CM cables are used in areas other than plenums and risers. These cables are resistant to the spread of fire and pass the UL 1581 Vertical Tray Flame Test.
Getting Full Category 5e Compliance
Using Category 5e cabling in your network installation does not necessarily achieve full Category 5e performance and 100BaseTX compliance. To achieve any category-rated performance, make sure all cabling components, including the modular plugs, trunk cables, and patch panels, are at least of the minimum category required. To achieve full Category 5e performance and 100TX compliance, all components must be Category 5e compliant and terminated properly according to EIA/TIA-568 TSB-36 and TSB-40 guidelines and tested with proper cable-certifying equipment.