Siemens DI-3 - User Manual

This document provides installation and wiring instructions for Siemens Smoke and Fire Detector Models DI-3, DI-3H, DI-3IS*, DI-A3, and DI-A3H. These instructions adhere to the installation guidelines of NFPA 72, National Fire Alarm Code, and CAN/ULC-S524, The Installation of Fire Alarm Systems.

Function Description

These detectors are designed to sense smoke and fire conditions within a protected area. They integrate into a compatible control unit to provide early warning of potential fire events. The DI-3IS model is specifically FM approved for intrinsically safe applications.

Important Technical Specifications

Voltage Rating: 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: 110µA maximum steady state.
Surge Current: 350µA peak surge upon application of power.
Alarm Current: 135mA maximum in alarm.
Remote Functions: Connections are available for listed remote lamps (RL-30 or equivalent), audible bases (ADB-3), or relays (RR-3), with a maximum draw of 40mA at 24V. CAUTION: Only one critical function remote should be used per circuit, as only one alarm per circuit is guaranteed.
DI-3IS Restriction: The DI-3IS model is FM listed only and should not use remote functions.
Temperature and Humidity Range:
- DI-3, DI-3H, DI-3IS, DI-A3, and DI-A3H: 32°F (0°C) to 100°F (37.8°C).
- DI-A3 and DI-A3H: 32°F (0°C) to 105°F (40.6°C).
- All models can be used in environments where the humidity does not exceed 93% (non-condensing).

Usage Features

Detector Placement: While no specific spacings are allocated for these detectors in clean air velocity applications (0 to 300 ft/min), a 30-foot center spacing (900 sq ft) from NFPA Standard 72 Chapter 5 and CAN/ULC-S524 is a practical guide. However, actual protected area may be less due to ideal conditions not always being met (e.g., smooth ceiling, no air movement, physical obstructions). It is crucial to follow installation drawings provided or approved by Siemens Industry, Inc. Detectors should be located on the ceiling, a minimum of 6 inches from a side wall, or on a wall, 6 inches from the ceiling, except in special circumstances like computer room underfloors where velocity may be between 300 and 1200 ft/min.

Special Ceiling Construction Factors: Ceiling obstructions significantly impact smoke and fire product movement. Obstructions like beams, joists, and ducts can create "dead air" spaces or channel smoke, affecting detector placement. For detailed guidance, refer to the Initiating Devices chapter of NFPA Standard 72 for specific construction types (e.g., beam, suspended, level, sloped, and peaked ceilings).

Air Currents: Air movement significantly influences how smoke and fire products travel. Detectors should be placed to intercept these products before they dissipate. Consideration must be given to windows, doors, and HVAC systems. Detectors should not be installed in the air stream of a room air supply diffuser if it may advantageously position the detector closer to an air return.

Pressure: Normal changes in atmospheric pressure have a negligible effect on detector sensitivity. However, lower air pressure at higher altitudes does have some effect on the sensitivity of ionization type detectors.

To Avoid Nuisance Alarms:

DI-3, DI-3H, DI-3IS: Do not locate where excessive smoke concentrations exist under normal conditions, in areas of prolonged high relative humidity causing condensation, or adjacent to oil burners, kitchens, or garages where exhaust fumes could trigger an alarm. Other causes include dust accumulation, high wind velocity, heavy steam concentrations, heavy pipe or cigar smoke, and certain aerosol sprays.
DI-A3, DI-A3H: Do not locate in areas of prolonged high relative humidity causing condensation, or adjacent to oil burners or in garages where exhaust fumes could trigger an alarm.

Detector Wiring: Siemens Industry, Inc. detectors are interconnected as shown in Figure 1. Wiring should be done according to the Wiring Connection drawing, the control panel manual, and the installation manual. Ensure proper documentation and adherence to the maximum number of detectors permitted per circuit.

Detector Mounting: The detector is provided with a separate base which attaches to a standard 4-inch square, 4-inch octagonal, or single gang electrical box. The depth of the box is determined by the National Electrical Code for the number and size of the conductors used.

Route all wires outward from the outlet box.
When the alarm LED wiring is critical, position the LED mark in the base in the intended direction (See Figure 2).
Mount base to outlet box and route wires through the hole in the center of the base.
Make connections directly to the base terminals, referring to Figure 1 for details.
After all bases are installed, including the end-of-line device, check loop continuity. Refer to system operation manual for procedure. If continuity is acceptable, remove jumper at each detector location and proceed with detector head installation.

Installation of Detector Head:

Align notch in detector cover to raised surface on outer ring of base (See Figure 3).
Push detector head into base and rotate clockwise to engage electrical connections. The detector will automatically stop and lock into place.
To remove, push detector head up into the base while rotating the detector head counterclockwise. Continue to rotate counterclockwise until stop is reached. Then pull downward to disengage from base.

Detector Sensitivity: The normal sensitivity range is found on the back of the detector. A decrease in sensitivity indicates the detector needs cleaning, ambient conditions have changed, or the detector is faulty.

DI-3, DI-3H, DI-3IS: Sensitivity is field adjustable via a potentiometer on the detector head face (See Figure 4). Adjustment towards "+" increases sensitivity; adjustment towards "-" decreases sensitivity. The adjustment range is ± 0.50 VDC of the nominal factory setting.
DI-A3, DI-A3H: Sensitivity is factory set and not field adjustable.

Testing: Testing should be performed by qualified personnel. Use a sensitivity jack test to directly measure detector sensitivity in its mounted position while powered by the system. Access the sensitivity test jack through five holes on the front face of the detector (See Figure 4). Use sensitivity tester Model TM-13 (P/N 315-086641). Test frequency should be in accordance with NFPA Standard 72. For GO/NO GO operation, use Siemens Test Gas, P/N 315-282747, following label instructions.

Maintenance Features

Cleaning: Dust accumulation can shift detector sensitivity. Periodic checks and light cleaning are necessary. The minimum test schedule can be found in NFPA 72, Chapter 7 (U.S.) and CAN/ULC-S537 (Canada). Cleaning intervals should be tailored to the individual detector environment. Clean by lightly brushing all open slots. Vacuum cleaning is also possible, but power should be disconnected to prevent alarms.

Repair: Detectors are not designed for thorough cleaning in the field. If sensitivity falls outside acceptable limits and cannot be adjusted back (where applicable), replace the detector head. Send removed heads to the nearest Siemens Industry, Inc. Authorized Service Center for servicing. CAUTION: Under no circumstances should the detector head be disassembled. No field repairs should be attempted. Detectors are factory repairable only.