Drager 8312088 PCB Safety Module PAC 5500
The Drager 8312088 is a printed circuit board designed for use in the PAC 5500 safety module system, part of Drager's gas detection and control equipment. This PCB functions as a power supply and logic controller, converting 230V AC input (50-60Hz) to 24V DC output (0.42A) for powering sensors, relays, and communication interfaces. It is typically installed in a control cabinet for industrial safety monitoring.
Electrical Specifications
Input voltage: 230V AC (nominal, range 207–253V), frequency 47–63 Hz. Input current: 0.15A typical. Output: 24V DC regulated, 0.42A (10W), with short-circuit and overvoltage protection. Ripple and noise: < 50 mVpp. Efficiency: 80% typical. The board includes a non-replaceable 1.6A slow-blow fuse on the primary side (soldered).
Circuit Functions
Key components: a switching regulator (Power Integrations TOPSwitch), a 24V to 5V linear regulator (LM7805) for logic, and an optocoupler-isolated relay driver. The board also includes a watchdog timer (TLC555) that resets the microcontroller if the program stalls. A green LED (PWR) indicates output voltage presence; a red LED (FAULT) indicates overcurrent or overtemperature.
Physical Characteristics
Board dimensions: 120 mm x 80 mm (Eurocard format). Thickness: 1.6 mm, FR-4 material. Mounting holes: 4 x M3 at corners. Connectors: a 6-pin terminal block (screw type) for AC input and 24V output, and a 10-pin header for connecting to the main logic board. The board is conformally coated (acrylic) for protection against condensation and dust.
Environmental Ratings
Operating temperature: -20°C to +55°C; storage: -40°C to +85°C. Humidity: 10% to 95% non-condensing. The board meets IP00 (bare board) but when installed in a PAC 5500 enclosure, the system achieves IP54. Vibration: 2 g (10–55 Hz). The board complies with UL 61010-1 and CE (EMC Directive).
Integration with PAC 5500 System
The 8312088 is a spare part for the Drager PAC 5500 controller, which monitors up to 8 gas sensors (for toxic gases, oxygen, or combustible gases). The PCB supplies power to the sensor input cards and the main CPU. It also provides isolated 24V for external alarm relays. In case of power failure, the board retains status via an optional backup capacitor (not included).
Diagnostics and Safety Features
The board includes a primary-side voltage monitor that shuts down the output if input exceeds 280V. It also has a thermal shutdown at 85°C case temperature. The output is protected against continuous short circuits by current foldback (limit 0.6A). A relay (normally energized) deactivates on fault, signaling a loss of power to the host controller.
Typical Applications
Used in industrial gas detection systems for chemical plants, refineries, and wastewater treatment facilities. The PCB is also compatible with Drager REGARD 3000 and REGARD 4000 controllers.
Ordering and Documentation
Drager part number: 8312088. The board is supplied in an anti-static bag. Manual: PAC 5500 Service Manual (Doc. No. 9023791). RoHS compliant (lead-free).
