The VD 500 seismic detector provides reliable detection and high immunity to false alarms when mounted on steel or concrete objects such as firearm cabinets, payment terminals, ATMs, safes, concrete walls etc. It detects intrusion attempts with explosives and mechanical tools such as diamond drills, cutting discs, grinding and thermal tools. The VD 500 includes digital signal processing (DSP) with an advanced detection algorithm. As a result, the detector is high performing with high immunity to external disturbances. The device has 3 separate detection channels: integration channel (detects weak signals), count channel (up to 4 events) and explosion channel (detects strong signals with short duration). The sensitivity and type of object to be protected is selected via a DIP switch.