OPTEX SL Beams & Enclosures — Photoelectric Specification and Selection Guide

Photoelectric specification and selection guide covering OPTEX's active infrared perimeter beam detectors (AX and SL Series) and TW-Series beam enclosures — a first line of defense for perimeter security.

Overview

OPTEX active infrared photoelectric beam detectors create a virtual trip wire at the perimeter (the "A Zone"), point-to-point. The lineup ranges from hardwired Standard/Advanced/Professional beam models to battery-powered, wireless-ready and iSeries units that need no trenching, plus TW-Series tower enclosures that conceal beam height/location for added security.

Standard, Advanced & Professional Beam Models (Hardwired)

All are Quad-beam, 99% beam blocking ratio, with 4-channel selectable frequencies, IP65 rated, ±90° horizontal / ±10° vertical alignment angle, operating range -31° to 140°F (-35 to 60°C), dimensions 17.6 x 3.1 x 3.8 in., powered 10.5–30VDC (QN/QDM) or 10.5–28VDC (QDP/QDM). Optional HU-3 heating unit extends the low end to -30°C.

Battery-Powered / Wire-Free Options

Wireless-ready versions (non-i, e.g. SL-350QFR) ship with an empty backbox that accepts any manufacturer's wireless transmitter. iSeries versions come with an Inovonics EN1941 wireless transmitter pre-installed, monitoring the DQ circuit, tamper, and primary alarm, plus an included BCU-4 module for low-battery monitoring.

Value of battery-powered systems: avoids costly/labor-intensive trenching; works where power isn't available (rooftops, remote sites); zero downtime for the end-user during install; flexible for changing site conditions (e.g. construction sites); easy add-on to existing video/access systems.

Key Features Explained

Sniper Viewfinder™

2x magnification telescope lens for high-visibility optical alignment even over long distances — standard on all SL models.

BAU-4 Automatic Beam Alignment Unit (optional, SL Series only)

Automatically and accurately adjusts optical alignment to peak performance, letting one technician align long-distance beams without help.

A.T.P.C. — Automatic Transmit Power Control (SL-QDM only, patent pending)

Automatically controls, adjusts, and optimizes beam power to maintain performance and decrease false/missed alarms caused by fog, frost, cross-talk, and signal saturation (e.g. from rising/setting sun).

Sunshine Protection Technology (SL-QDM / SL-QDP only)

Triple-layer construction for better performance against external light sources (sun, mercury-vapor and fluorescent lights): a front cover filter that removes visible light, IR-bandpass photodiodes tuned to the beam wavelength, and a light-disturbance compensation circuit that differentiates the double-modulated beam signal from other light sources.

D.Q. Output (Environmental Disqualification)

Sends a trouble signal when beam strength drops below acceptable levels for more than 20–40 seconds due to fog, snow, or heavy rain. Available on: AX-100TF/200TF/100TFR/200TFR/100TFRi/200TFRi, SL-350QFR/QFRi, SL-350QDP/650QDP, SL-350QDM/650QDM.

Four-Channel Selectable Frequencies

Lets you stack two photobeams (e.g. on a pole or in an AX-TW200 enclosure) for added perimeter protection without frequency interference. Available on most AX/SL models except the base QN line.

Hardwired Installation Tips

• Distance: longer runs cause bigger voltage drops, which can cause missed/false alarms — use thicker gauge wire for long runs (max 18 gauge).
• Power supply: choose one rated for the correct amperage to cover the beam's current draw.
• Wiring: select conductor count based on which outputs you need to monitor (tamper, alarm, D.Q., power — varies by model).
• Zoning: home-run wiring is recommended even when beams could be series-wired, for easier troubleshooting and zone identification.

Beam Enclosures (TW Series)

Suited for all OPTEX AX and SL Series wired, IP, and wireless battery-powered beam models. Concealing beams in an enclosure hides their number and mounting height from potential intruders, increasing security, and allows lighting or a fixed camera to be added in a special top housing.

• Free-standing AX-TW models: 360° unobstructed view, enabling back-to-back installation to cover a full perimeter.
• Free-standing AX-TWS models: 180° view for side detection where wall mounting isn't practical.
• Wall-mounted AX-TWM models: 180° view, flush mount.
• Available heights: 20", 3'3", 6'6", 9'9".
• Durable extruded/anodized aluminum frame with acrylic materials; beams mountable at any height/direction inside the tower.
• Optional housing for lighting or a fixed camera; anti-tamper and beam mounting plates included.
• Free enclosure assembly when a site plan is provided.

Enclosure Part Numbers

Concrete Mounting (AX-TWEB)

1. Dig an 18"x18"x18" (minimum) hole; add rebar/support if needed and pour concrete.
2. Insert the TWEB bracket and cable access conduit while the concrete is still wet.
3. Secure the enclosure base to the TWEB bracket bolt heads using the included redhead bolts (bolts can also be added to existing concrete).
4. Assemble the enclosure body and covers onto the base.

Common Enclosure Accessories

• AX-TWLUXE: head extension for lighting (bulb not included).
• AX-TWEB: concrete floor bracket for free-standing floor-mount enclosures.
• AX-TWH24V: 12V or 24V, 250mA non-polarity heater and thermostat.
• AX-TWFAN 12V/24V: 100mA (12V) or 150mA (24V) fan.
• AX-TWCAM: CCTV extension head for enclosure (camera not included).
• AX-TWAA: anti-climb tamper.
• AX-TWCAB: guy wires for enclosures in extreme wind conditions.
• AX-TWSTB: lateral supports for enclosures.
• AX-TWSM: pole/wall mount L bracket for AX-TW50/100/200/300.
• BAU-4: automatic beam alignment tool (SL series only).

Other Common Accessories

• PIE-1 PoE Encoder: integrates beams with leading IP camera control systems (order in pairs).
• ABC-4 Anti-Bird Cap: keeps birds/small animals off the detector and protects it from rain/snow.
• HU-3 Heating Unit: for hardwired SL models and AX-TN/AX-TP models.
• BC-4 Back Cover: conceals the rear of a pole-mounted SL Series detector.
• PSC-4 Pole Side Cover: conceals the gap between two back-to-back pole-mounted SL Series detectors.
• CBR-4 Conduit Bracket: required to run conduit to SL Series detectors.

Total Security Solutions — Layered Perimeter Example

OPTEX beams pair well with additional outdoor motion detection to build strategic detection zones inside the perimeter without running additional wiring, and can trigger cameras, lights, or notify authorities on detection. Example product families referenced in this guide: SIP-5030 (outdoor PIR for CCTV activation), REDSCAN RLS-3060SH (laser plane/wall detector with 8 independently adjustable zones, integrates with leading VMS/access/analog platforms), BX-80NRi and HX-40RAMi (battery-powered outdoor dual-PIR detectors), and VXI-RDAMi (battery-powered dual-technology detector) — paired with Inovonics EN5040T repeaters and EN7290/EN4232MR receivers.

About OPTEX

Founded over 30 years ago, OPTEX has built a worldwide reputation for quality, innovation, and technical excellence in perimeter security, from residential to critical infrastructure applications.

Support

OPTEX, Inc. — Security Division, 18730 S. Wilmington Ave., Unit 100, Rancho Dominguez, CA 90220. Phone: 800-966-7839. Email: sales@optexamerica.com. www.optexamerica.com | www.optex-vms.com