Lathem Sonachron DWA-S - Manual (Page 5)

Page 2
INTRODUCTION
The DWA-S is a single circuit signaling device which can be
used as a bell ringer or on/off controller. It is capable of retaining
up to 1440 separate events for each day of the week in memory
plus a floating lunch and break schedule which can be activated
with a single key on the keypad or a remote switch. Automatic
adjustment for daylight savings time change is also provided. A
liquid crystal display on the front of the unit displays the current
time (in 12 or 24 hour format), date, and day of the week, bell or
on/off control status, programming prompts, and indication of
operation on standby power. A 24-button keypad is used for
setting time, programming events, manual operation of bells or
controls, initiating lunch or break bells, and on/off control of the
schedule. Access to programming functions and manual keys
(MANUAL, START LUNCH, and START BREAK) is controlled by
a user defined security code.
The time keeping ability of the DWA-S is dependent on the
power source frequency. A switch setting selects operation
based on 50 or 60 Hz. During A.C. power failures, the unit
switches to a quartz crystal time base and a 6 volt battery allows
the unit to continue to keep time and retain all data for 10 days.
Upon power resumption, the battery automatically recharges with
current limited to 1.5 Amperes.