Another common cable rating is cm which denotes communications cable such as cat 5e or cat 6 networking cable.
Cm rated cable means.
Such cables are limited to residential or other small applications where the number of communication cables used is very little.
Cmr cable often called riser rated cable is constructed to prevent fires from spreading floor to floor in vertical installations.
Cm cmg communications cable for general purpose use.
Among all these terms cm cmr and cmp are the most common ethernet cable ratings specified by the national electric code nec.
They can be installed anywhere except plenums.
Plenum cables are the highest standard and can safely be substituted for any other cable type such as riser cm cl2 or cl3 cables.
In the case of cm the standard outlines general use or use in cases where the fire code does not place any restrictions on cable type.
When installing ethernet cable in walls or ceilings you may encounter terms like cm cmr cmp or some others like pvc and lszh.
Cables often have a cm cmg or cmr rating as defined by the national electrical code nec.
Or cmr rated cable.
Some of the cables we carry aren t nec rated so they re missing from the table below.
In practice communications cable generally means network cable type cm cables are generally the minimum jacket ratings suitable for in wall installation of network cables and are appropriate for installation inside a residence or a single story commercial building.
These cables do not spread flame to the top.
Cm cmg are the most commonly used commercial grade communication cable.
That doesn t mean that your local electrical inspector won t allow these to be installed in wall but it does raise the possibility.
Cl2 and cl3 cable doesn t reduce smoke or gases but minimize the possibility of shock.
This is the next step up.
Cable jacket ratings uses and substitutions when installing cabling in walls and ceilings it is important to use cables that meet the local code requirements.
Local codes are typically based on the national electric code nec published by the national fire protection association.
Often this type of cable meant for home usage will carry an x suffix signifying that it is intended for use in buildings where the cable is enclosed in a non combustible conduit.
All of the canare cables belden 1808a and bjc yc 2 s video cable.
Do you know what these terms really mean and which one does your project actually need.
All of them are in practical terms suited for in wall.
A cmr rating means the cable can be used in the risers of commercial buildings because they limit the spread of flames better than cables in the cl cm family.
Cmx is a residential grade cable.
Guide to cable ratings.