If you maintain Edwards EST fire alarm systems, choosing the right SIGA-series intelligent detector is critical for reliable fire protection. Edwards’ Signature series offers a full range of photoelectric smoke detectors, heat detectors, multi-criteria detectors, and duct smoke detectors — each designed for specific environments and detection needs.
This guide covers every SIGA detector type, helping fire alarm technicians and building managers select the right replacement detector for their Edwards system.
Understanding the Edwards SIGA Detector Family
All SIGA (Signature) detectors share the same intelligent analog/digital communication protocol, making them compatible with EST3, EST4, iO-series, QuickStart, and EDGE fire alarm control panels. Each detector continuously reports its analog sensor value to the panel, allowing for precise sensitivity adjustment, drift compensation, and pre-alarm notification.
SIGA Photoelectric Smoke Detectors
Photoelectric smoke detectors are the most commonly installed SIGA detectors. They use a light-scattering chamber to detect smoke particles from smoldering fires:
- SIGA-PS — The original Signature photoelectric detector. Widely installed in office buildings, schools, and hospitals. Still available as a replacement part.
- SIGA-PD — Next-generation photoelectric detector with improved sensitivity and drift compensation. Direct replacement for SIGA-PS in most applications.
- SIGA-OSD — Current-production intelligent optical smoke detector. Features enhanced chamber design for better discrimination between real smoke and nuisance particles.
- 2251FB — Intelligent plug-in photoelectric detector for older EST systems. Uses the same base footprint as SIGA detectors.
Best for: General-purpose smoke detection in offices, corridors, hotel rooms, classrooms, and patient rooms.
SIGA Heat Detectors
Heat detectors are essential in environments where smoke detectors would cause false alarms — kitchens, mechanical rooms, parking garages, and dusty warehouses:
- SIGA-HRS — Intelligent fixed-temperature (135°F) heat detector with 15°F/minute rate-of-rise sensing. The most popular Edwards heat detector for general commercial applications.
- SIGA-HRD — High-temperature (190°F) fixed-temperature heat detector for boiler rooms and other high-ambient-temperature areas.
- SIGA-HFD — Fixed-temperature-only heat detector without rate-of-rise, designed for spaces with rapid normal temperature changes.
Best for: Kitchens, mechanical rooms, boiler rooms, parking garages, storage areas, and any location prone to smoke-detector false alarms.
SIGA Multi-Criteria & Multi-Sensor Detectors
These advanced detectors combine multiple sensing technologies to reduce false alarms while maintaining fast fire response:
- SIGA-PHD — Multi-sensor smoke and heat detector combining photoelectric and thermal sensing. Excellent for areas where you need both detection types in a single point.
- SIGA-IPHS — Multi-sensor detector with enhanced algorithms for discriminating between real fires and cooking/steam/dust nuisance sources.
- SIGA-OSHD / SIGA-OSHCD — Optical smoke and heat combination detector with 135°F fixed temperature and 15°F/min rate-of-rise. Available in standard (OSHD) and Canadian-listed (OSHCD) versions.
- SIGA-PHCD — Multi-sensor smoke, heat, and CO detector. The most advanced SIGA detector, providing three-criteria detection in a single device.
Best for: Areas with nuisance alarm history, mixed-use spaces, dormitories, and applications requiring sleeping-area CO detection.
SIGA Duct Smoke Detectors
Duct smoke detection is required by code in HVAC systems to prevent smoke from spreading through ductwork:
- SIGA-SD SuperDuct — Intelligent addressable duct smoke detector with field-replaceable sensor board (SIGA-SDPCB). Mounts directly to ductwork with sampling tubes.
- Air Sampling Tubes — Available in 8″ (6261-001), 42″ (6261-003), and 120″ (6261-010) lengths for different duct sizes.
- SIGA-SDPCB — Replacement PCB/intelligent sensor kit for the SuperDuct. Replace just the electronics without removing the housing from the duct.
CO Detectors
- SIGA-COD — Intelligent carbon monoxide detector for addressable systems. Can be combined with smoke detectors for multi-criteria CO/fire detection.
- 260-CO — Carbon monoxide alarm and trouble detector for conventional applications.
Detector Bases: Choosing the Right One
Every SIGA detector requires a compatible mounting base. Edwards offers several options:
- SIGA-SB — Standard 6″ detector base. The most common choice for new installations.
- SIGA-SB4 — 4″ base with trim skirt for mounting on 4″ square electrical boxes.
- SIGA-IB — Isolator base with built-in fault isolator. Required on Class A SLC loops per NFPA 72.
- SIGA-RB / SIGA-RB4 — Relay bases with Form C dry contact for local device control (fan shutdown, damper closure, etc.).
- SIGA-AB4G — Audible sounder base that emits a local alarm tone when the detector activates.
SIGA Modules for System Integration
Complete your Edwards system with SIGA intelligent modules for connecting conventional devices, controlling outputs, and monitoring waterflow/tamper switches. Popular models include the SIGA-CT1 (single input), SIGA-CR (control relay), SIGA-MM1 (monitor), and SIGA-WTM (waterflow/tamper).
Shop Edwards SIGA Detectors at Life Safety Consultants
Life Safety Consultants stocks the complete range of Edwards SIGA detectors and accessories. Most orders ship within 24-48 hours, and our team can help you identify the right detector for your application. Browse our full Edwards fire alarm parts inventory or call 1-888-557-0558 for expert assistance.
