SELENA
Multifunctional LED Clock
USER MANUAL V32D
KERA TECHNOLOGIES INC. 2013
www.ledclocks.com
38
clock will ignore the data received too soon after the previous packet.
One ASCII time code packet must be broadcast by the Master once every second ( in Lathem protocol once a minute ), at the
beginning of each second.
Data structure is shown below:
Format 0: (CR)(LF)I(^)(^)DDD(^)HH:MM:SS(^)DTZ=XX(CR)(LF)
Format 1: (CR)(LF)I(^)WWW(^)DDMMMYY(^)HH:MM:SS(CR)(LF)
Format 2: (CR)(LF)IQYY(^)DDD(^)HH:MM:SS.sss(^)LD
Format 3: 0003(^)YYYYmmdd(^)/-)HdHdMdMdD#(CR)(LF)
where:
CR = Carriage Return
LF = Line Feed
I = Time Sync Status (space, ?, *)
^ = space separator
DDD = Day of Year (001 - 366)
DD = Numerical day of month ( ^1 - 31 )
YYYY = Year ( 2002, 2003, 2004, etc… )
WWW = Day of Week ( MON, TUE, WED.. etc..)
MMM = Month ( JAN, FEB, MAR...etc…)
YY = Year without century ( 02, 03, 03 etc…)
HH = Hours ( 00-23 )
: = Colon separator
. = Decimal separator
+,- = positive or negative UTC offset ( time difference from UTC )
# = On-Time point
MM = Minutes ( 00-59 )
SS = Seconds ( 00 - 60 )
sss = Miliseconds ( 000 - 999 )
L = Leap second Indicator ( Space, L )
HdHd = UTC time difference hours ( 00 - 23 )
MdMd = UTC time difference minutes ( 00 - 59 )
D = Daylight Savings Time indicator ( S,I,D,0 )
TZ = Time Zone
XX = Time Zone Switch Setting ( 00-23 )
NOTE:
To use the
SELENA clock as the Master in the ASCII Time Code Format “0 or 3”
enable both
Fn 32 and Fn 46
and select the required Format with Functions Fn 11, Fn 12 and Fn 13.
Note, that only the Format 0 or 3 may be selected in the Master.
NOTE: ONLY
ONE
MASTER IS ALLOWED TO OPERATE ON THE SAME NETWORK OR A COLLISION WILL OCCUR.
A Twisted Pair cable must be connected
“IN PARALLEL”
to all clocks in the system. Additional clocks may be added at any
time and/or taken away from the system either by Selecting/Deselecting the appropriate Sync Control functions or physically.
Clocks that are not enabled as slaves may continue to operate as stand alone.
Normally, up to 64 clocks can operate within a single RS485 communication network wiring without additional signal boosting.
It is advisable that for each 64 slaves one
Opto-Repeater
be used to amplify the signal. Such repeater is an Option #841 in
SELENA systems and is normally installed inside the clock that is purchased with that option, or a third party signal booster
may be installed.
MINUTE IMPULSE Sync System
for 2-wire, 3-wire and Reverse Polarity 1 Minute and 1/2 Minute Impulse
( Optional Feature )
The MINUTE IMPULSE Synchronization slave mode may be activated by enabling the Function
Fn 47
.
ONLY 2 WIRES, Line A is used by the SELENA clocks to achieve successful synchronization.
SELENA clocks will respond to the Minute Pulses within the range of + 5 to + 35 VDC presented at the appropriate external
inputs.
The current load requirement on Line A inputs are very low and are equivalent to an Input Resistance of 4.7 to 10 Kohm per
input.
The functions Fn 11 and Fn 12 select the specific protocol for the Minute Pulse sync as follows:
