18/4 AWG Riser Security Alarm Cable - CMR/CL3R Rated, Shielded, 1000ft Gray

This is the four-conductor shielded riser cable for the devices on a security or access control system that need power and signal in one pull on a noisy route: four 18 AWG stranded bare copper conductors, black, red, white, and green, under an overall aluminum foil shield and 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 card reader with power and a data pair, a keypad with power and a bus pair, a motion detector with power and a tamper loop, an intercom station with power and audio: each is a four-conductor run, the shield keeps the data or audio pair quiet past the lighting and power wiring it shares a riser or a wall with, 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, and FPLR covers the same spaces on a fire alarm system. 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.
• Overall aluminum foil shield. 100% coverage against induced noise from lighting, motor, and power circuits sharing the riser or the wall, for the reader, keypad, and audio conductors in the bundle.
• Black, red, white, and green. The standard four-conductor coding, so power and data pairs are identifiable at both ends without a meter.
• PVC insulation and jacket. Flexible, with a 0.015 in jacket wall over the shield.
• 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.
• 4.88 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 card readers and keypads on access control doors that need power and a data pair in one pull, security keypads and touchscreens on a four-wire panel bus routed past lighting or motor circuits, motion detectors and glass-break sensors with power and a tamper loop, intercom and entry-phone stations with power and audio, RS-485 and panel bus runs where the manufacturer accepts a shielded untwisted pair, riser runs between a security panel and a floor's zone expander or reader controller alongside power wiring, power-limited fire alarm circuits that call for a shielded stranded four-conductor cable, 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 and the route is electrically noisy.

Good to Know

Ground the shield's drain at the panel or controller end only and tape it back at the device end; a shield grounded at both ends becomes a loop that picks up the noise it was meant to reject. Check the reader or panel manufacturer's wiring guide before you pull, since Wiegand and RS-485 runs have maximum lengths at 18 AWG and some specify a twisted pair, and a foil shield adds capacitance that can shorten the rated run on a high-speed bus. 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 reader drawing 200 mA at 300 ft loses about 0.8 V, and a 12 V strike drawing 0.5 A at 200 ft loses about 1.3 V; keep a strike or maglock off the same cable as a reader if you can, and if you can't, put the data pair farthest from the power pair, since the shield helps against noise from outside the cable but does nothing about crosstalk inside it. Keep the circuits in their classes: Class 2 and Class 3 circuits can share this cable, but a Class 1 circuit can't, a fire alarm circuit can't share a cable with a security circuit, 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, CMR, and FPLR cover risers and general use but not return-air plenums; a run through a plenum ceiling needs a CL3P cable. If the route is quiet, the unshielded 18/4 riser does the same job for less and terminates faster. The jacket isn't UV stabilized or rated for wet locations or burial, so an outdoor reader or keypad should be fed through conduit or from a cable rated for it.

Specifications