DEIF AL8-2

Technical Specifications Channels: 8 independent alarm inputs Input Voltage: 48 V DC (standard; 24 V DC and 110 V DC variants available) Input Type: Dry contact (open/closed) or NPN/PNP transistor, configurable Indicator: High-brightness LED per channel, color-coded lens (red standard) Audible Alarm: Integrated electromechanical horn or piezoelectric buzzer, ≥ 80 dB at 1 m Relay Outputs: 8 form-C (SPDT) alarm relays, 5 A @ 250 V AC Common Relay: 1 group alarm relay, 5 A @ 250 V AC Power Consumption: ≤ 15 W at nominal voltage Operating Temperature: -10 °C to +55 °C Storage Temperature: -25 °C to +70 °C Humidity: 5 % to 95 % RH, non-condensing Protection: IP40 front panel (IP54 with gasket option) Mounting: 19-inch rack mount, 3U height, or panel mount Weight: Approximately 1.2 kg Approvals: IEC 60068, IEC 60945, DNV, ABS, BV marine type approval

Functional Features First-up alarm identification with flashing indicator and latch Selectable alarm sequence: ISA 18.1 standard sequences (A-1 through F-1) Push-button controls: Acknowledge, Reset, Lamp Test, Silence Group alarm relay for remote SCADA or DCS integration LED brightness adjustment for day/night operation Configurable fail-safe (energized-to-alarm) or non-fail-safe input logic

Application Scenarios Marine engine rooms, switchgear rooms, and cargo control stations Power plant and substation auxiliary alarm systems Industrial process plants requiring hardwired alarm backup to DCS HVAC and fire-safety monitoring panels in commercial buildings

Material Composition Enclosure: Cold-rolled steel sheet, powder-coated RAL 7035 Front Fascia: Polycarbonate film with engraved alarm labels Indicators: Diffused polycarbonate lenses with surface-mount LEDs Printed Circuit Board: FR-4 with conformal coating Relays: Industrial-grade plug-in relays with silver-nickel contacts Horn: ABS housing with piezoelectric diaphragm

Structural Features 3U 19-inch rack-mount chassis with removable terminal blocks Eight labeled alarm windows arranged in two rows of four Four membrane push buttons below indicator array Integrated horn grille on front panel Rear terminal strip for power, inputs, and relay outputs

Working Principle Each alarm input is optically isolated and monitored by a microcontroller. When an input changes to alarm state, the corresponding LED flashes, the common horn sounds, and the channel relay energizes. Pressing Acknowledge latches the alarm (LED steady, horn silence); Reset clears only after the fault condition returns to normal.

Installation Requirements Mount in a clean, dry control panel with access to rear terminals Wire inputs in shielded cable, separate from AC power wiring Connect common negative of all field contacts to annunciator common terminal Use fuse or circuit breaker rated 2 A upstream of power input Observe polarity for DC-powered inputs and horn circuit

Usage Precautions Do not exceed relay contact ratings; use interposing relays for heavy loads Perform lamp test and acknowledge/reset sequence during commissioning Verify fail-safe logic matches safety requirement before energizing field Replace blown indicator LEDs only with same voltage and color Keep front-panel labels legible; replace film if worn or faded