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Solid State Starters
SOLID STATE STARTERS
The OptiView Control Center will accommodate either
of two dif fer ent YORK Liquid Cooled Solid State Start-
ers (LCSSS). Later production chillers are equipped with
the Mod "B" LCSSS. This style LCSSS contains the
Sil i con Con trolled Rectifi er (SCR) as sem blies, an in te -
grat ed Log ic/Trigger Board and in ter fac es the OptiView
Con trol Cen ter via a serial data com mu ni ca tions link
and hardwired re lay contacts. Ear li er vintage chillers
are equipped with the pre vi ous ver sion LCSSS that in-
ter fac es the OptiView Control Center via a mul ti plexed
data in ter face and hardwired relay contacts. This earlier
vintage LCSSS hous es the SCR as sem blies and Trig-
ger Board; a sep a rate Logic Board is located inside the
OptiView Con trol Cen ter. Microboard Pro gram Jumper
JP39 must be po si tioned to invoke the appropriate
Microboard/Pro gram op er a tion for the start er applied
(refer to Table 1).
Mod "B" Serial Interface LCSSS (Refer to Fig. 39)
A complete description, theory of operation and trou-
ble shoot ing instructions of this LCSSS are contained
in YORK Service Manual 160.00-O2. The following
de scribes the interface and interaction of the LCSSS
with the OptiView Control Center.
As shown in Figure 39, the LCSSS contains a single
Logic/Trigger printed circuit board. This board per forms
the following functions:
• Generates the SCR trigger pulses
• Receives start/stop commands from the
Microboard
• Transmits status and fault data to the Microboard
• Generates all LCSSS initiated Safety and Cycling
shutdowns.
The Logic/Trigger Board is powered by +24VDC
from the OptiView Control Center Power Sup ply. The
OptiView Control Center Microboard (J15) com mu -
ni cates with this board via a 1200 baud 0/+5VDC serial
data com mu ni ca tions link. If this communications link
does not operate prop er ly, cor rect Microboard J15 se ri al
port op er a tion can be ver i fi ed using the Serial In puts and
Out puts di ag nos tic pro ce dure in the "Di ag nos tics and
68
SECTION 11
SOLID STATE STARTERS
(REFER TO FIG. 39 - 41)
Trou ble shoot ing" section of this book. The STOP re lay
con tacts on the Logic/Trig ger Board as sure a pos i tive
shut down on all LCSSS ini ti at ed shut downs.
After power has been applied to the system, the
Microboard will attempt to establish com mu ni ca tions
with the Logic/Trigger Board. If unsuccessful within 10
at tempts, the Microboard initiates a Cycling shutdown
and dis plays "LCSSS INITIALIZATION FAILED"
on the System Details line of the OptiView Control Cen-
ter dis play. The Microboard will continue to establish
com mu ni ca tions until successful. Also, at power-up, the
Log ic/Trigger Board reads wire jumpers in its connec-
tor J1 to de ter mine the LCSSS model applied (refer to
160.00-O2). If an invalid jumper con fi g u ra tion is read,
the Logic/trig ger Board ini tiates a Cycling shutdown
and "LCSSS - IN VALID CUR RENT SCALE SE-
LEC TION" is dis played on the Sys tem Details line of
the OptiView Con trol Cen ter Display. The model des ig -
na tion is trans mit ted to the Microboard for display on
the MO TOR Screen. This des ig na tion de ter mines the
al low able range for the Full Load Amps (FLA) Setpoint
and Start Cur rent Setpoint. There are 4 LCSSS models:
7L, 14L, 26L and 33L. Each model has an al low able
Full Load Amps (FLA) range and Start Current range
as list ed below.
Communications between the Microboard and Logic/
Trig ger Board are in the form of master/slave. The
Microboard is the master and the Logic/Trigger Board is the
slave. The Logic/Trigger Board sends two types of data to
the Microboard: Status data and Fault data. Af ter suc cess ful
ini tial iza tion, the Microboard sends a data re quest every 2
sec onds. Normally, the Logic/Trig ger Board re sponds to
each request. However, if the Microboard does not re ceive
a response to 10 con sec u tive requests, the Microboard
ini tiates a Cycling shutdown and displays "LCSSS - SE-
RI AL COM MU NI CA TIONS" on the System De tails
line of the OptiView Con trol Center display. In ad di tion,
the Log ic/Trigger Board will initiate the same Cy cling
shut down if it does not re ceive a data request from the
Microboard after 10 suc ces sive attempts to send data.
Anytime the Logic/Trigger Board initiates a Cycling or
Safety shutdown, it opens its STOP contacts that are
connected in series with the OptiView Control Cen ter's
1R (K18) RUN relay coil. The contacts re main open as
long as the condition exists. The open STOP contacts
interrupt the circuit to 1R causing it to
FORM 160.54-M1(503)
YORK INTERNATIONAL
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