SMPTE/EBU systems are primarily used within broadcasting and television industry.

This system is characterized by serial EBU LTC (longitudal) time code control and operation of connected clocks (both analogue and digital). The time code is distributed by a Master Clock or Time Central with SMPTE/EBU LTC output. Each movement in connected clocks has its own microprocessor to receive the time code, detecting the position of the hands and thereafter automatically set the hands to correct time.

Clocks in Westerstrand SMPTE/EBU-system require mains supply of 230V AC and are connected to SMPTE/EBU code using 2-polar screw terminal. When connected clocks have received and accepted the LTC, they will step forward to correct time by rapid impulses. Digital clocks are automatically set to correct time within 2 minutes after connection. In case the LTC would disappear, the built-in quartz crystal will take over control of correct time.

In case of power failure the clocks are temporarily stopped. When power returns the hands (analogue clocks) will automatically, and rapidly, be set to 12-position and wait for an LTC message and thereafter to correct time. With the option running reserve, the clocks will continue to work during the power failure for 12 hours. Digital clocks are automatically set to correct time within 2 minutes after power has returned and the clock has recived a LTC message.