York MAXE OPTIVIEW YK, Service Instructions Manual

Page: 70 / 180

YORK INTERNATIONAL
70
FORM 160.54-M1(503)
• Kilowatt Hours (KWH) Reset - This allows the ac-
cu mu lat ed KWH to be set to a desired starting val ue
in the event the BRAM has to be
fi eld re placed. This
must never be arbitrarily performed.
To assure the chiller is not permitted to run for ex tend ed
periods with the supply line voltage outside of ac cept able
limits, the Logic/Trigger Board compares the ac tu al 3-
phase line voltage to the thresholds established with
the Supply Line Voltage Range setpoint. Each sup ply
voltage application has an allowable upper and low er
limit. If the supply voltage goes above or below these
limits continuously for 20 seconds, the logic trig ger
Board initiates a Cycling shutdown and displays “
LC-
SSS - HIGH SUPPLY LINE VOLTAGE ” or “ LCSSS
- LOW SUPPLY LINE VOLTAGE ” as ap pro pri ate.
The chiller will automatically restart when the line volt-
age is within the acceptable range.
While the chiller is running, the Microboard will close
or inhibit opening of the Pre-rotation Vanes (PRV), as
re quired, to limit the compressor motor current to the
Cur rent Limit or Pulldown Demand Limit setpoint (30%
to 100% FLA) that is in effect. The Microboard cal cu lates
the “% Full Load Amps” (FLA) by dividing the high-
est phase of the 3-phase motor current, re ceived from
the Logic/Trig ger Board, by the value pro grammed for
the
FULL LOAD AMPS setpoint. “ % FULL LOAD
AMPS ” is displayed on the MOTOR Screen. If the
motor current increases to the extent that the “ % FULL
LOAD AMPS ” reaches 100% of the Current Limit
Setpoint, the PRV are inhibited from further open ing
until the motor cur rent decreases to <98% of the Cur-
rent Lim it setpoint. If the motor current increases to the
ex tent that the “
% FULL LOAD AMPS ” is 104% of the
Current Limit setpoint, the PRV will be driven closed
until the “
% FULL LOAD AMPS ” de creas es to 102%
of the Cur rent Limit setpoint. The PRV open ing will
then be in hib it ed until the “
% FULL LOAD AMPS ”
decreases to <98% of the Current Lim it setpoint.
LD04648
NOTES:
9 – “CONDOR” Power Supply; 13 – “POWER ONE” Power Supply
*
FIG. 39 – MOD “B” LIQUID COOLED SOLID STATE STARTER (LCSSS) - INTERFACE
POWER
SUPPLY
MICRO
BOARD
I/O
BOARD
LCSSS
LOGIC / TRIGGER
BOARD
STOP CONTACTS
SERIAL COMMUNICATIONS
CONTROL CENTER
SOLID STATE STARTER
GND
+24 VDC
J15
6
*
J30 / P30
6
12
J1
J19
J2
2 36 37
3
2
1
MO
T
O
R
CONTR
O
LLER
SHUTDO
WNS
ST
OP
ST
AR
T
GND
RX
TX
5
4
3
2
1
TB2
TB1
24
16
53
START / STOP
STARTER (MOTOR CONTROLLER) INITIATED SHUTDOWN
115VAC
16
53
1
TB6
– TB6 –
25 24
2 36 37
25
16
1
TB5
TB1
J2
Solid State Starters