Logic/Trigger Board Indicator Leds; Relay Functions; Figure 6 - Lcsss - Logic/Trigger Board Detail - York SSS 7L-B Operation Manual

SECTION 3 – LOGIC/TRIGGER BOARD

LOGIC/TRIGGER BOARD INDICATOR LEDS

The Logic/Trigger Board contains only two LEDs.
Since all of the shutdown messages are displayed on
the OptiView Control Center, there is no need for
LEDs to annunciate a shutdown condition. The two
LEDs are used to verify that the serial communications
link is working.
CR6 is the Receive LED. This LED will flash green
every 2 seconds to indicate that the Logic/Trigger
Board has received data from the OptiView Control
Center. (Refer to Figure 6 on page 18 for location
of LED.)
CR7 is the Transmit LED. This LED will flash red ev-
ery 2 seconds to indicate that the Logic/Trigger Board
has sent data to the OptiView Control Center. (Refer to
Figure 6 on page 18 for location of LED.)

RELAY FUNCTIONS

Relay K1 shall provide a hardware shutdown signal to
the OptiView Control Center via wires 16 and 53. The
relay will provide a normally open set of contacts that
are driven closed when the LCSSS is operating satis-
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J1
TB-2 TB-1 J4
FIGURE 6 - LCSSS – LOGIC/TRIGGER BOARD DETAIL
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factorily, and the contacts will open when the LCSSS
initiates a Cycling or Safety shutdown. These contacts
will remain open until the cause of the shutdown has
been rectified.
Relay K2 controls the operation of the closed loop
coolant pump. When the Micro Board commands the
LCSSS to run, the main system microprocessor, via an
output driver, causes the K2 relay contacts to close. As
long as the K2 contacts are closed, the closed loop cool-
ant pump will run. When the Micro Board commands
the LCSSS to stop, the main system microprocessor, via
an output driver, causes the K2 relay contacts to open
(provided all of the thermistor temperatures are below
110°F). This will stop the closed loop coolant pump.
Therefore, the closed loop coolant pump may start and
stop with the compressor motor. Also, the K2 relay will
be energized by the main system microprocessor when
any heatsink temperature exceeds 110°F regardless
of whether the chiller is running or not. When the
temperature falls below 110°F, the main system micro-
processor will de-energize K2 relay causing the pump
to stop.
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CR7 CR6 U15 RAM CHIP
FORM 160.00-O2
ISSUE DATE: 04/30/2019
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00287VIP
U16 EPROM
JOHNSON CONTROLS
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