The TD450 is a four channel detector with advanced “logic” features. These include direction sensing and delay / extend timing for queue detection and traffic phase extensions.
The TD450L has programmable speed / vehicle headway thresholds for controlling “too fast / too close” warning signs.
879FT0022 - TD452L 4 Channel logic - 240V AC (Pre-Order)
879FT0036 - TD454L - 12/24V AC/DC (Pre-Order)