What Is CL3 Cable?

CL3 security cable is a class 3 cable rated at 300 volts for use with power-limited circuits as per Article 725 of the National Electrical Code (NEC). Typical applications include signal wires, intercom wiring, security, room and wall speakers, internet and TV wall installations. Cables have pure copper conductors with color-coded PVC insulation. These cables have a semi-rigid PVC jacket and some versions have an aluminum polyester screen to prevent electromagnetic interference (EMI). The cable is similar to CL2 cables, except that CL2 cables have a lower maximum voltage rating of 150 volts.

CL3 Cable Types

Allied Wire and Cable stocks two versions of CL3 rated wire: CL3R and CL3P.

CL3R Riser Cable

You can use CL3R cable for in-wall installations and in risers but not in fabricated ducts, environment air ducts and plenum assemblies. CL3R cables may have an optional EMI shield made from aluminum/polyester foil. 

CL3P Plenum Cable

You can use CL3P cable in ventilation ducts and fabricated risers, as well as everywhere you can use CL3R wire. Apart from that, the main difference to CL3R wires is you can't get a shield with CL3P wires primarily due to its NEC rating, although you can buy it with aluminum armor.

CL3 Cable Construction

CL3R and CL3P cables have similar construction.


CL3 wire uses a solid or stranded copper wire to ASTM Standards B286, B-3 and B-8. The number of cores available is between 2 and 12.


All versions have a semi-rigid (S-R) polyvinylchloride (PVC) insulation with a minimum thickness of 0.007 inches. Conductors are color-coded.


Cables have a premium grade PVC jacket with a minimum thickness of 0.015 inches.


You can specify CL3R wires with an optional aluminum polyester foil shield.

Drain Wire

Some versions of both cable types have a separate stranded tinned copper drain wire.

Cable Applications

Although listed as a security cable, CL3 cable supports many uses, including:

  • Speaker cables: 2 core room and building speaker cables with or without a shiel
  • Ripcord: 2 core ripcord for use with power-limited circuits
  • HDMI: High-speed HDMI video cables for HDR TV and video projectors
  • Cat5 and Cat6 Ethernet cables: High bandwidth Ethernet cables
  • Alarm: Internal alarm wiring
  • CCTV: Closed-circuit TV installations

CL3 Cable Specifications

Specifications for CL3 cables include:

Conductor Materials: Solid or Stranded Copper
Number of Conductors: 2, 3, 4, 5, 6, 7, 8, 10 and 12
Wire Sizes: 20 AWG to 12 AWG
Insulation: Color-coded semi-rigid PVC
Jacket Material: Semi-rigid PVC
Drain Wire: Stranded copper drain wire in some versions
Shield: Aluminum polyester foil shield in some CL3R cables
Maximum Voltage: 300 volts
Temperature Rating CL3P Cables: 0°C to +75°C
Temperature Rating CL3R Cables: -20°C to +75°C

CL3R Compliance

  • NEC Type CL3R Cable Article 725
  • NEC Type CMR Cable Article 800
  • California State Fire Marshal for security cable
  • Restriction of Hazardous Substances (RoHS) compliant

CL3P Compliance

  • NEC Type CLP Cable Article 725
  • NEC Type CMR Cable Article 800
  • California State Fire Marshal