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The Siemens OP921 is a commercial smoke detector designed for compatible Cerberus PRO and Siemens fire alarm systems. It uses optical light-scattering technology to detect smoke while continuously monitoring its sensitivity and operating condition.
The detector features a low-profile housing, tri-color LED indication, automatic environmental compensation, and built-in ISOtechnology for improved signaling-line-circuit reliability. Siemens currently lists the OP921 as an active product.
The OP921 connects to a compatible Siemens two-wire signaling line circuit and occupies one device address. It is polarity-insensitive during standard Class B installation, although installers must maintain polarity when using Class X isolation operation.
The detector communicates alarm, trouble, sensitivity, and maintenance information to the connected control panel.
The OP921 installs on a compatible Siemens DB-11 or DB-11E detector base. These bases support standard 4-inch square, octagonal, or single-gang electrical boxes.
An optional LK-11 locking kit helps prevent unauthorized detector removal.
Suitable for:
The OP921 is designed for compatible Siemens systems, including selected:
Always verify panel firmware, detector-base compatibility, and project approvals before installation.
Manufacturer: Siemens
Model: OP921
Stock Number: S54320-F4-A2
Product Type: Commercial Optical Smoke Detector
Detection Technology: Light-Scattering Optical Sensing
Wiring: Two-Wire Signaling Line Circuit
Device Addresses Required: One
Status Indicator: Tri-Color LED
Isolation: Built-In ISOtechnology
Operating Temperature: 32°F to 120°F (0°C to 49°C)
Mounting Bases: DB-11 or DB-11E
Open-Area Listing: UL 268
Duct Listing: UL 268A
Canadian Listings: ULC S529 and ULC S530
Approvals: UL, ULC, FM, and CSFM
Product Status: Active
Always verify electrical ratings and approvals using the label and documentation supplied with the specific detector.
The Siemens OP921 is commonly installed in commercial fire alarm systems requiring dependable smoke detection, individual device identification, continuous diagnostics, and built-in circuit isolation.
| Weight | 2 lbs |
|---|---|
| Dimensions | 5 × 5 × 5 in |
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The Siemens OP921 is a commercial smoke detector designed for compatible Cerberus PRO and Siemens fire alarm systems. It uses optical light-scattering technology to detect smoke while continuously monitoring its sensitivity and operating condition.
The detector features a low-profile housing, tri-color LED indication, automatic environmental compensation, and built-in ISOtechnology for improved signaling-line-circuit reliability. Siemens currently lists the OP921 as an active product.
The OP921 connects to a compatible Siemens two-wire signaling line circuit and occupies one device address. It is polarity-insensitive during standard Class B installation, although installers must maintain polarity when using Class X isolation operation.
The detector communicates alarm, trouble, sensitivity, and maintenance information to the connected control panel.
The OP921 installs on a compatible Siemens DB-11 or DB-11E detector base. These bases support standard 4-inch square, octagonal, or single-gang electrical boxes.
An optional LK-11 locking kit helps prevent unauthorized detector removal.
Suitable for:
The OP921 is designed for compatible Siemens systems, including selected:
Always verify panel firmware, detector-base compatibility, and project approvals before installation.
Manufacturer: Siemens
Model: OP921
Stock Number: S54320-F4-A2
Product Type: Commercial Optical Smoke Detector
Detection Technology: Light-Scattering Optical Sensing
Wiring: Two-Wire Signaling Line Circuit
Device Addresses Required: One
Status Indicator: Tri-Color LED
Isolation: Built-In ISOtechnology
Operating Temperature: 32°F to 120°F (0°C to 49°C)
Mounting Bases: DB-11 or DB-11E
Open-Area Listing: UL 268
Duct Listing: UL 268A
Canadian Listings: ULC S529 and ULC S530
Approvals: UL, ULC, FM, and CSFM
Product Status: Active
Always verify electrical ratings and approvals using the label and documentation supplied with the specific detector.
The Siemens OP921 is commonly installed in commercial fire alarm systems requiring dependable smoke detection, individual device identification, continuous diagnostics, and built-in circuit isolation.
| Weight | 2 lbs |
|---|---|
| Dimensions | 5 × 5 × 5 in |
Your Payment information is processed securely. We do not store credit card details, nor have access to your credit card information.
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