Biral BTD-350 Thunderstorm Detector

Description

Standalone Thunderstorm Detection to 83km

The BTD-350 Thunderstorm Detector by Senseca UK (formerly Biral) is a standalone sensor that reliably detects all forms of lightning activity within a range of 83km (45 nautical miles). Its unique quasi-electrostatic operating principle delivers an exceptionally low false alarm rate and — uniquely — the ability to warn of overhead lightning risk before the first discharge occurs.

Key Features

• 83km Detection Range — Exceeds US FAA requirements for aerodrome use
• Pre-flash Warning — Detects strong electric fields and charged precipitation to warn of lightning risk before the first strike
• All Lightning Types — Detects cloud-to-ground, cloud-to-cloud, and intra-cloud lightning discharges
• Very Low False Alarm Rate — Passive electrostatic principle is immune to radio interference (the primary cause of false alarms in traditional detectors)
• High Detection Efficiency — 95% for single flash; 99% for storms with 2 flashes; 99.9% for storms with 3+ flashes
• Rapid Response — Lightning flashes detected and ranged within 2 seconds; electric field alerts within 5 seconds
• Optional Direction Finder — Reports direction to nearest degree using electromagnetic wave detection (3kHz–1MHz band)
• Flexible Communication — Ethernet or RS422 serial output; ASCII data string for easy integration
• Virtually Maintenance Free — No moving parts; passive sensing principle
• Marine Certified — Salt spray, vibration, and EMC certified for on and offshore marine applications
• Aviation Compliant — Meets FAA performance requirements; supports enhanced CAP437 thunderstorm reporting

How It Works

The BTD-350 operates by sensing changes in the atmospheric electric field in the frequency band of 1–47 Hz — the electrostatic signature of lightning charge transfer, corona discharge, and strongly-charged aerosol movement. Because radio emissions occur at far higher frequencies, the sensor is inherently immune to radio interference. Mains power noise (50/60 Hz) is removed by both analogue and digital filtering.

Electric field disturbances from developing overhead thunderstorms can trigger a warning alert within 5 seconds — providing advance warning before any lightning has struck. Once lightning begins, each flash is detected, ranged, and logged within 2 seconds of initiation.

Certifications & Compliance

• CE Certified — EMC General: EN 61326:2013
• CE Certified — EMC Marine: EN 60945:2002
• Corrosion resistance: EN 60945:2002 / EN 60068-2-52:1996
• Vibration: EN 60068-2-6:2008
• EN50536:2011+A1:2012 — Class 1 Detector
• IEC 62793 — Class A Detector
• RoHS and WEEE Compliant

Applications

• Aviation — airports, helipads, aerodrome weather stations
• Marine & offshore — vessels, rigs, ports
• Wind energy sites and solar farms
• Mining, construction, and outdoor industrial operations
• Sports venues, events, and recreation facilities
• Military and defence installations
• Meteorological and research stations