TYPE 08—Rauland 2410 Digital Clocks (24Vac and 120Vac)

Rauland 24Vac or 120Vac digital clocks initialize to 12:01 AM when first powered up. During normal operation, the clocks maintain time by counting the 60Hz AC line frequency. When the line voltage drops below 120Vac, the digital clocks start rapidly advancing at two minutes per second. After applying power to the master clock and entering system selection code 08, the master initializes to 12:01 AM and applies normal voltage to the digital clocks, causing them to set to 12:01 AM.

After initial power-up, any time change made at the master clock causes the SYS LED to illuminate, indicating that the digital clocks are about to be corrected. At the 56th second, the master clock removes power from the digital clocks, then at the 59th second applies low voltage to the clocks, causing them to rapidly advance to the new time.

When the new time is reached, the master clock reapplies the normal voltage. If the digital clocks become unsynchronized with the master, they can be manually reset using the [9]=SYNCH. CLOCKS function. See page 3-5.

When a manual clock advance is initiated, the SYS LED illuminates, power is removed at the 56th second, and a low voltage is applied at the 59th second, causing the clocks to advance to the current master time, at which point normal voltage is reapplied.

When a daylight saving mode, either forward or back, is initiated at 2:00 AM Sunday, the master removes power from the clocks and applies low voltage, causing the clocks to rapidly advance to the new time, either 1:00 AM or 3:00 AM, at which point normal voltage is reapplied.

Every 24 hours at 12:00:56 AM, the master clock removes power from the clocks, then reapplies power at 12:00:59 AM, causing the clocks to set to 12:01:00 AM, thereby synchronizing the clocks with the master clock.

See Figures B-10and B-11on the next page for the 120Vac and 24Vac wiring.

B-12

24A715/24A715M Master Clock Installation Manual