18/4 Riser Security Alarm Cable - CMR/CL3R Rated, 7 Strand Copper, 1000ft Gray

This is the four-conductor riser cable for the devices on a security system that need power and signal in one pull: four 18 AWG stranded bare copper conductors, black, red, white, and green, under a gray PVC jacket listed CL3R under NEC Article 725 for Class 3 power-limited circuits (and by the code's substitution rules for Class 2 as well), CMR under Article 800 for communications, and FPLR under Article 760 for power-limited fire alarm circuits. A keypad with power and a data bus, a motion detector with power and a tamper loop, a siren with drive and tamper, an intercom station with power and audio, a door with a strike and a request-to-exit: each is a four-conductor run, and 18 AWG is heavy enough to carry the power leg a long way without the voltage drop that 22 AWG would give. The 7-strand conductors bend around a wall cavity and land in a terminal block more easily than solid wire.

CL3R and CMR cover the vertical runs between floors of a multi-story building and every ordinary in-wall and in-ceiling run that isn't a return-air plenum. It's unshielded, which is the right construction for power, contacts, and the low-speed keypad buses most panels use, and it keeps the cable slim and the price down. The cable is ETL Listed and RoHS compliant, and it comes in a 1000 ft pull box with sequential footage marks on the jacket.

Features

• Riser rated three ways. CL3R under NEC Article 725, CMR under Article 800, and FPLR under Article 760, so it's listed for riser shafts, vertical runs between floors, and general in-wall and in-ceiling use on security, control, communications, and fire alarm circuits alike, and the CL3R listing covers Class 2 circuits under the code's substitution rules.
• Four 18 AWG stranded bare copper conductors. Power and signal in one pull, with about half the loop resistance of 22 AWG, on 7-strand conductors that bend around a wall cavity and seat in a terminal block without fighting.
• Black, red, white, and green. The standard four-conductor coding, so power and data pairs are identifiable at both ends without a meter.
• Unshielded. The right construction for power, contacts, and low-speed keypad buses, and the easier one to terminate.
• PVC insulation and jacket. Flexible, with a 0.015 in jacket wall that strips cleanly.
• Gray jacket. Reads as general-purpose low-voltage in a wall or a tray, and stays distinct from red fire alarm and blue data cable.
• 300 V, 75 °C. The ratings a Class 2, Class 3, or power-limited fire alarm circuit calls for.
• 4.78 mm outer diameter. Slim enough to bundle and fish through a wall or a tight ceiling.
• ETL Listed, RoHS compliant.
• 1000 ft pull box. Sequential footage marks on the jacket; pays out from the box without a spool stand, and the box stacks in a van.

Where It Fits

It suits security keypads and touchscreens on a four-wire panel bus, motion detectors and glass-break sensors with power and a tamper loop, sirens and strobes with drive and tamper conductors, intercom and entry-phone stations with power and audio, access control doors that need a strike and a request-to-exit in one pull, riser runs between a security panel and a floor's zone expander, and any four-conductor low-voltage run through the walls and risers of a home, apartment building, office, or store where the ceiling space isn't a return-air plenum.

Good to Know

Run the voltage-drop calculation on the pair that carries power. An 18 AWG pair is about 13 ohms per 1000 ft round trip, so a 12 V keypad drawing 150 mA at 300 ft loses about 0.6 V, and a 12 V siren drawing 1 A at 200 ft loses about 2.6 V; for a heavy siren or a strike on a long run, keep the run short or move the power supply closer. Most panel keypad buses are low-speed and run fine on untwisted conductors, but check the panel manufacturer's wiring guide for the maximum bus length at 18 AWG and for any panel that specifies a twisted or shielded pair. Keep the circuits in their classes: Class 2 and Class 3 circuits can use this cable, but a Class 1 circuit can't, and the NEC requires power-limited wiring to stay separated from power conductors in raceways and boxes. Stranded conductors want a ferrule or a proper fold-back before they go under a screw terminal; a stray strand is the short that takes a zone into trouble. CL3R and CMR cover risers and general use but not return-air plenums; a run through a plenum ceiling needs the CL3P version. The jacket isn't UV stabilized or rated for wet locations or burial, so an outdoor siren or contact should be fed through conduit or from a cable rated for it.

Specifications

Usually ships in 1 - 2 business days.