Riser cable (CMR) / backbone cable is a cable that is run between floors in non-plenum areas. The fire requirements on riser cables are not as strict as the requirements on Plenum cables (CMP). There are both Cat5e riser (CMR) cables and Cat6 riser (CMR) cables.
It is always possible to use a plenum cable in place of a riser cable, but it is not possible to utilize a riser cable in areas designated for plenum cable. Many different types of cable, including twisted-pair, coaxial, HDMI, and DVI, are created in both plenum and riser.
This cable is essential in multi-story structures, as it runs from the service entrance point up through the different levels of the building, supplying voice, data, and video services. The name is derived from its purpose of 'rising' between the floors.
The cable is part of a building’s backbone system. Other components of the backbone system include cable pathways, telecommunications closets, equipment rooms, and related hardware, as well as support facilities.
A riser cable, as the name suggests, is a type of cable designed specifically for vertical applications. It serves as a conduit for transmitting signals and power between different floors of a building, making it an indispensable component of modern infrastructure. Riser cables are commonly used in office buildings, residential complexes, data centers, and other commercial structures where efficient communication and connectivity are paramount.
These cables are meticulously engineered to adhere to safety and performance standards, ensuring reliable and secure data transmission across various levels of a building. Riser cables are constructed with fire-resistant materials to mitigate the risk of fire spreading between floors, making them suitable for installations where fire safety is a concern.
Riser cables come in various types, each designed to cater to specific requirements and environments. Some of the most common types of riser cables include:
Optical Fiber Riser Cables: These cables utilize optical fibers to transmit data using light signals. Optical fiber riser cables offer high bandwidth and are capable of transmitting large amounts of data over long distances, making them ideal for applications such as high-speed internet connections and data centers.
Coaxial Riser Cables: Coaxial riser cables consist of a central conductor surrounded by insulating and shielding layers. They are commonly used for transmitting cable television signals, internet connectivity, and surveillance camera feeds.
Twisted Pair Riser Cables: Twisted pair cables consist of pairs of insulated copper wires twisted together. They are commonly used for transmitting telephone and Ethernet signals within a building.
Composite Riser Cables: These cables combine multiple types of cables, such as optical fibers and copper wires, within a single sheath. Composite riser cables provide versatility and can accommodate various communication needs simultaneously.
Riser cables find applications in a wide range of scenarios, enabling efficient communication and connectivity across different floors of a building. Some notable applications include:
Data Centers: In data centers, where the processing and storage of vast amounts of information take place, riser cables play a pivotal role in connecting servers, switches, and networking equipment across different floors. These cables ensure uninterrupted data flow and support the seamless operation of critical IT infrastructure.
Office Buildings: Modern office spaces demand reliable connectivity for various operations, such as internet access, VoIP communication, and video conferencing. Riser cables facilitate the transmission of data and voice signals between different floors, enabling efficient communication and collaboration.
Residential Complexes: In residential buildings, riser cables provide residents with essential services like cable television, broadband internet, and landline telephone connections. These cables ensure that occupants can stay connected and entertained while enjoying the comforts of their homes.
Educational Institutions: Schools and universities often require interconnected communication systems to support online learning, campus-wide Wi-Fi, and administrative operations. Riser cables establish the necessary connectivity infrastructure for these educational institutions.
Healthcare Facilities: In hospitals and medical facilities, reliable communication is crucial for patient care and administrative tasks. Riser cables enable the seamless exchange of medical data, electronic health records, and communication between different departments.
One of the most critical aspects of riser cables is their fire-resistant properties. Riser cables are subjected to strict fire safety standards to prevent the spread of fire between different floors of a building. In the event of a fire, these cables are designed to withstand high temperatures and emit minimal smoke, reducing the risk of fire-related casualties and damage.
Riser cables are typically labeled with fire safety ratings, such as "CMP" (Communications Plenum) or "CMR" (Communications Riser), indicating their suitability for specific installation environments. CMP cables are suitable for use in plenum spaces – the air-handling areas of a building – where fire safety regulations are particularly stringent. CMR cables, on the other hand, are designed for installation in riser areas and provide a higher level of fire resistance compared to standard cables.
It is important to note that using non-compliant or inadequate cables in a riser environment can pose significant safety risks and lead to regulatory violations. Proper selection and installation of riser cables are crucial to ensuring the safety of building occupants and the overall integrity of the infrastructure.
Installation Best Practices
When installing riser cables, adherence to best practices is essential to ensure optimal performance, safety, and longevity. Some key installation considerations include:
Cable Pathway: Plan the cable pathway carefully to minimize bends, kinks, and stress on the cables. Proper cable management helps maintain signal integrity and reduces the risk of damage during installation and maintenance.
Support and Securing: Use appropriate cable supports, such as J-hooks and cable trays, to secure the cables and prevent sagging. Proper support prevents strain on the cables and ensures they are not exposed to unnecessary tension.
Bundling: Avoid overbundling or tightly packing multiple cables together, as this can lead to overheating and signal interference. Maintain proper spacing between cables to allow for adequate ventilation.
Connector Integrity: Ensure connectors are properly terminated and securely fastened to prevent signal loss and maintain data integrity.
Labeling and Documentation: Clearly label cables and maintain accurate documentation of the installation. This simplifies troubleshooting, maintenance, and future upgrades.
Planning for the Future
Since cable requirements are different for the various services, planning for future use needs can be tricky. Especially since future uses of the backbone wiring can range from the predictable to the entirely unknown. Due to this unknown variable, it is typically suggested to separate riser systems for different applications (such as voice and data) that follow parallel routes through pathways, closets, and equipment rooms.
A riser cable is a type of conduit that runs vertically between floors of a multi-story structure, connecting the service entrance point to all the different levels of the building, through which voice, data, and video are distributed.
