EC74/50S
365-Day Four Channel Time
Control
I. INTRODUCTION
The EC74/50S is a 365-day, four channel, microprocessor-
based time control. It is ideal for lighting or HVAC control in
which time-of-day scheduling is common. The programmable
momentary feature provides a 1 to 59 second momentary
contact closure for applications such as bell ringing, urinal
flushing, synchronous wall clock correction and operating
mechanical latching relays. The enclosure is made of durable
noncorrosive plastic for years of life.
II. SPECIFICATIONS
Programming Capabilities
• Seven-day programming using 365-day calendar with
eighth day as a holiday program.
• 16 holiday durations programmable by date.
• 50 set points. A set point can be assigned to any day or to
any combination of days. Each of the 4 circuits can be
independently programmed.
• Each set point can be either an ON, OFF or momentary
type event. A programmable momentary duration of 1-59
seconds can be entered for each of the 4 circuits.
• 12-hour (A.M./P.M.) or 24-hour clock format.
• Automatic daylight-saving time changeover with yearly
compensation.
• Keyboard override until next programmed event.
• 3-second stagger up between loads.
• Leap year corrected.
• Keyboard programming.
• LCD display of time-of-day and day of week. Circuit status
indicated by LEDs (if LED is lit, output relay is energized as
a result of a programmed ON or an override).
