LTRx-512 Installer’s Guide
Wiring Diagrams
32
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ELECTRONIC CODED CLOCKS
Clocks run normally with 120 VAC power. For any bells or clock correction, the generator prestart
relay (SK1) first turns on for the signal-generator to reach frequency. SK1 turns on at the 00 second
after a programmed time or manual bell time. Then relay SK2 turns on for 3 seconds, from the 10
th
to
the 13
th
second, to apply the generator signal (coded cup start signal) onto the 120 VAC. Bell circuits
then turn on for 3 seconds, in the order listed below, applying the generator signal onto the 120 VAC
for decoding by the coded cups. The bell relay contacts must connect in parallel with the normally open
contacts of relay SK2. If it is not time for a clock correction signal, then SK1 turns off at the 59
th
second. At the 57
th
minute of each hour, SK2 turns on from 57:54 to 58:02, applying the 8-second
hourly correction generator signal onto the 120 VAC. At 5:57 AM and 5:57 PM (12-hr correction),
SK2 turns on from 5:57:54 to 5:57:08, applying a 14-second 12-hour correction generator signal onto
the 120 VAC. For daylight savings, the clocks advance to the proper time by normal 12-hour
correction, not at 2:00 AM. The order of each relay operation is listed below (see NOTE for Type 15
re: SK1):
RELAY
FROM
TO
FROM
TO
SK1 Gen. Prestart (hourly corr.)
H:57:00
H:59:00
SK2 Start Signal (hourly corr.)
H:57:10
H:57:13
H:57:54 H:58:02
SK1 Gen. Prestart (12-hour corr.)
H:57:00
H:59:00
SK2 Start Signal (12 hour corr.)
5:57:10
5:57:13
5:57:54
5:58:08
SK1 Gen. Prestart (bells)
H:MM:00 H:MM:59
SK2 Start Signal (bells)
H:MM:10 H:MM:13
Bell Circuit 6
H:MM:20 H:MM:23
Bell Circuit 5
H:MM:25 H:MM:28
Bell Circuit 4
H:MM:30 H:MM:33
Bell Circuit 3
H:MM:35 H:MM:38
Bell Circuit 2
H:MM:40 H:MM:43
Bell Circuit 1
H:MM:45 H:MM:48
For Masters including firmware versions
prior to V2.17 only:
NOTE: The LTRx-512 was designed for
clocks that do not require a generator pre-
start to set the frequency level. Clocks
using this pre-start may not work with the
LTRx-512 older than V2.17
All circuits should be fused or protected by a circuit breaker (10Amp maximum)
TYPE 14
Bells should not be scheduled for:
HH:58:SS
