CMR Cable (Riser Rated Cable)
Full Name: Communications Riser Cable.
CMR cable is specifically designed for vertical riser or shaft installations between building floors. Subjected to more rigorous testing and constructed with enhanced flame-retardant materials, CMR cable meets stricter NEC fire resistance requirements to prevent fire from spreading across floors. Consequently, its superior fire safety performance typically results in a higher cost compared to standard CM cables.
- Key Characteristic: This rating is for fire resistance in vertical shafts. It passes a test (UL 1666) that measures the cable’s ability to prevent flames from propagating from one floor to another through a vertical riser shaft.
- Typical Use: Primarily for vertical runs between floors inside a dedicated riser shaft or space (like a elevator shaft or conduit). It is not rated for use in air plenums.
Specification
28AWGX1PAIR+26AWGX2C
| Item Name | 28AWGX1PAIR | 26AWGX2C |
| Conductor: | TS7/0.127±0.007 | TS7/0.16±0.007 |
| Insulation Diameter: | 0.85±0.08 | 1.00±0.10 |
| Jacket Overall Diameter: | 3.90±0.20 |
24AWGX1PR / 24AWGX2PR / 24AWGX3PR / 24AWGX4PR
| Item Name | Conductor | Insulation Diameter | Jacket Overall Diameter |
| 24AWGX1PAIR | TS7/0.20±0.007 | 0.98±0.08 | 3.40±0.20 |
| 24AWGX2PAIR | TS7/0.20±0.007 | 0.98±0.08 | 4.80±0.20 |
| 24AWGX3PAIR | TS7/0.20±0.007 | 0.98±0.08 | 5.00±0.30 |
| 24AWGX4PAIR | TS7/0.20±0.007 | 0.98±0.08 | 5.50±0.30 |