| 摘要 |
A vehicle security system for a curtain-sided trailer 1 has a TIR cord 6 which passes around substantially all of the circumference of the cargo area, the security system comprising means for passing a signal through the cord 6, and means for monitoring the signal, the monitoring means being arranged to detect that the signal remains within one or more predetermined boundaries, and to activate an alarm if the signal moves outside of the boundaries. The signal may be electrical, ultrasonic or optical. |
