Introduction
The Cerberus Pyrotronics DI-3, DI-A3, and DI-B3 fire smoke detectors operate on the ionization principle, responding to visible smoke or invisible combustion products. These detectors are designed for commercial, industrial, and institutional fire detection and extinguishing applications and are approved under UL 268 & UL 268A. The DI-B3 requires a Series 3™ air duct housing.
Description
The DI-3 Series detectors are plug-in, two-wire ionization detectors. The DI-3 features adjustable sensitivity, while the DI-A3 and DI-B3 have fixed sensitivity optimized for high air flow applications. Each detector uses self-compensating dual ionization chambers and a stable solid-state amplifier-switching circuit. One chamber detects combustion products, while the other acts as a reference to stabilize sensitivity against environmental changes. When combustion products enter the sampling chamber, chamber current decreases, producing a voltage change. Upon exceeding a pre-determined threshold, an alarm is signaled to the control unit, and the detector latches until reset by the control panel.
Factory preset sensitivity can be monitored and adjusted in the field using the Cerberus Pyrotronics sensitivity tester (TM-13). A sensitivity test jack on all models and an adjustment screw on the DI-3 allow for adjustments without removing the detector head from its base.
Detectors utilize a low-profile surface mounting base (DB-3S) compatible with 4" octagonal or single gang outlet boxes, or the audible base (ADB-3) for 4" square deep wiring boxes. Both bases feature screw-clamp terminals, self-wiping contacts for reliability, and provisions for an optional concealed locking mechanism. The DI-3 is designed for open area protection with air velocities up to 300 feet per minute.
Mounting and Application Data
Mounting Data: The diagram shows the detector base (DB-3S or ADB-3) designed for mounting to standard 4-inch octagonal or square wiring boxes. It illustrates dimensions and indicates the location of the detector identification label and the red LED lens.
The DI-A3 is recommended for high air velocity applications (e.g., computer room underfloor areas) and is UL listed for 0-1200 feet per minute (FPM). The DI-B3 is specifically designed for use with Cerberus Pyrotronics Series 3 air duct housings in air duct applications with velocities of 400-4000 FPM.
Models DI-3H, DI-A3H, and DI-B3H are available for high altitude applications (3000 to 8000 feet above sea level).
The DI-3 and DI-A3 can operate remote alarm lamps (RLI1, RLI2, RL-30, RL-40) or an auxiliary relay (RR-3/3S, rated 120 VAC, 2 Amp resistive). The DI-B3 can use the remote relay from the Series 3 air duct housing (AD-3 with DA-3SR Relay Board, rated 125 VAC/24 VDC, 3 Amp resistive).
When multiple detector/relay combinations are used on one circuit, the zone module's current limit restricts the number of guaranteed actuations to one per zone.
The DI-3, DI-A3, DI-B3, DI-3H, DI-A3H, and DI-B3H ionization detectors are UL Listed and also FM, CSFM, and NYMEA approved.
An FM approved, intrinsically safe DI-3IS is available for use with System 3 intrinsically safe zone modules (ZS-30 or CZM-1).
Application Data: These detectors are compatible with other Cerberus Pyrotronics System 3 detectors and can be intermixed on the same zone circuit, with a maximum of thirty (30) detectors per circuit (excluding thermals or manual stations).
The standard spacing guideline is 30-foot centers (900 sq. ft.) per NFPA 72, applicable under ideal conditions (smooth ceiling, no air movement, no obstructions). This should be a starting point, and engineering judgment is required for detector location and spacing. Avoid mounting near ventilating or air conditioning outlets, and consider effects of exposed joists or beamed ceilings.
Engineer and Architect Specifications
- The ionization smoke detector shall be a dual chamber, plug-in unit mounting to a twist/lock base and be UL listed.
- The smoke detector shall operate on a two-wire circuit and include an alarm-indicating LED.
- DI-A3 ONLY: Specifically designed for high air velocity applications (0-1200 ft./min.). Detectors not UL listed for this range are not accepted.
- DI-B3 ONLY: Specifically designed for air ducts (400-4000 FPM) when used with Series 3 air duct housings. Detectors not UL 268A listed for this range are not accepted.
- Models DI-3H, DI-A3H, or DI-B3H are available for use in altitudes of 3000-8000 feet above sea level.
- Field adjustment and monitoring of detector sensitivity shall be possible without removing the detector head from its base, providing a discrete electrical value. Test methods not providing an output signal proportional to smoke concentration are not considered equal.
- The base assembly shall be twist/lock design with screw-clamp terminals, self-wiping contacts, and accept other compatible plug-in detectors.
- A security lock shall be installed where tamper-resistant installation is required.
Technical Specifications
| Parameter | Value |
|---|---|
| Current Requirements | Normal: 100µA (350µA peak surge upon power application) Alarm: 80mA |
| Voltage Range | 21 ±3 VDC |
| Operating Temperature | +32°F (0°C) to +100°F (38°C) per UL |
| Humidity | 0-93% Relative Humidity |
| Air Velocity |
|
Note: Consult factory for special application requirements. For additional product information, refer to Cerberus Pyrotronics DI-3 technical bulletin, P/N 315-082300.
Typical Wiring
The detector, or group of detectors, shall require a two-wire circuit using #18 AWG thermoplastic fixture wire enclosed in conduit, or #18 AWG limited energy shielded cable without conduit, if permitted by local codes.
Optional auxiliary DPDT relays or remote alarm lamps shall be installed where indicated.
The detector assembly shall be a Cerberus Pyrotronics DI (insert number) with DB-3S mounting base, ADB-3 audible base, or Series 3 air duct housing.**
*DI-3, DI-3H only
**DI-B3, DI-B3H only
Wiring Diagram Description: The schematic illustrates a typical two-wire connection to a compatible control unit initiating circuit. It shows connections to terminals 5 and 6. A break in the wire run is required under terminal 5 for supervision. The diagram also depicts an end-of-line device, noting polarity if applicable. Connections for a listed remote lamp (RL-30 or equivalent), audible base (ADB-3), or relay (RR-3) are shown, with a maximum of 40mA at 24V per detector. A caution states that only one critical function remote should be used per circuit, as only one alarm per circuit is guaranteed.
NOTE: The Models DI-3, DI-3H, DI-3IS*, DI-A3, and DI-A3H are rated at 16-25.7 VDC with a 3-volt peak to peak maximum ripple. Supervisory current is 110µA max steady state, with a 350µA peak surge upon power application, and 135mA max in alarm.
*NOTE: The DI-3IS is FM listed only. Do not use remote function with the DI-3IS.
For intrinsically safe applications utilizing the DI-3IS with a CZM-1, consult the wiring diagram on the CZM-1 catalog sheet (#5006).
Ordering Information
| Model No. | Description | Shipping Wt. | |
|---|---|---|---|
| Lb. | Kg. | ||
| DI-3 | Ionization smoke detector | 1 | .45 |
| DI-3IS | Ionization smoke detector (Intrinsically Safe) | 1 | .45 |
| DI-3H | Ionization smoke detector (High Altitude) | 1 | .45 |
| DI-A3 | Ionization smoke detector (High Air Velocity) | 1 | .45 |
| DI-A3H | Ionization smoke detector | 1 | .45 |
| DI-B3 | Ionization smoke detector (Duct Use Only) | 1 | .45 |
| DI-B3H | Ionization smoke detector (High Altitude -- Duct Use Only) | 1 | .45 |
| DB-3S | Low profile mounting base | 1 | .45 |
| ADB-3 | Audible base | 1 | .45 |
| DB-LK | Series 3 base locking kit | .5 | .23 |
| AD-3I | Series 3 air duct housing (See Catalog Sheet #6124) | 5 | 2.25 |
| DA-3SR | Duct Relay Module (Conventional) | 0.5 | .23 |
| SA-3I | Series 3 self-contained air duct housing (See Catalog Sheet #6124) | 7 | 3.15 |
| RR-3S | Remote relay (DPDT) | 1 | .45 |
| RL-30 | Remote alarm lamp (Incandescent) | 1 | .50 |
| RL-40 | Remote alarm lamp (Incandescent) | 1 | .50 |
| GP-7A | Aerosol detector tester | 7 | 3.15 |
| GC-7 | Replacement gas container for GP-7A | 1 | .45 |
| RLI-1 | Remote alarm lamp LED | .50 | .23 |
| RLI-2 | Remote alarm lamp LED | .50 | .23 |
NOTICE: The use of other than Cerberus Pyrotronics control equipment will be considered a misapplication of Cerberus Pyrotronics equipment and as such void all warranties either expressed or implied with regards to loss, damage, liabilities and/or service problems.
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