70
YORK INTERNATIONAL
MANUAL RESET SAFETIES (1 Fault and Lockout)
A Manual Reset Safety will shut the affected system
down and lock it out whenever the safety threshold is
exceeded.
After a system has shut down and locked out, a fault
display indicated the last system fault will appear on the
STATUS display message. This is accessible by press-
ing the STATUS key.
To reset a locked out system, turn to affected system
switch on the Microprocessor Board (Page 81) to the
OFF position.
CAUTION: Before returning a locked out system to
service, a thorough investigation of the cause
of the fault should be made. Failure to re-
pair the cause of the fault while manually
allowing repetitive restarts may cause fur-
ther expensive damage to the system.
Each of the Manual Reset Safeties will be discussed in
detail below.
High Motor Current Safety
The High Motor Current Safety assures that motor life is
not diminished due to operating beyond the current rat-
ing of the motor. The micro begins monitoring motor cur-
rent after 3 seconds of operation. If motor current ex-
ceeds 120% FLA after 3 seconds of operation, the com-
pressor will shut down. After 4 seconds of operation,
motor current must be less than 115% FLA as long as
the compressor continues to run. This safety applies to
all chillers with all versions of 031-01652-001 EPROMs.
An example of the High Motor Current display is shown
below:
NOTE: Do not confuse FLA and RLA. FLA (full load run-
ning amps) is approximately 1.2 x RLA. RLA (run-
ning load amps) specified on the motor name-
plate, is typical current demand under rated op-
erating conditions in a fully loaded system. There-
fore, do not expect to see 100% FLA when the
system is fully loaded. In this condition, currents
may run approximately 65-86% FLA.
S Y S # 1
H I G H
M T R
C U R R
S Y S # 2
H I G H
M T R
C U R R
INDIVIDUAL SYSTEM START INHIBIT SAFETIES
An Individual System Start Inhibit Safety will inhibit the
respective system from starting when a safety threshold
is exceeded and allows automatic restart after the con-
dition causing the inhibit clears. Restart will occur only
after anti-recycle timers are satisfied and demand re-
quires.
When the chiller is shut down on one of these safeties,
a message will appear on the STATUS display informing
the operator of the problem. This is accessible by press-
ing the STATUS key.
Low Oil Temperature Inhibit Safety
*
Low oil temperature assures the compressor is not al-
lowed to start until the oil is free of liquid refrigerant. This
is accomplished by assuring that the oil temperature is
a minimum of 15°F above ambient temperature.
In effect, this safety assures that the compressor oil
heater is operating and that is has been on long enough
after power application for all refrigerant to have been
expelled from the oil.
NOTE: This safety will only be operational if the chiller
is equipped with an I/O Expansion Board.
An example of the Low Oil Temp Safety is shown below:
S Y S # 1
O I L
T E M P
I N H I B
S Y S # 2
O I L
T E M P
I N H I B
* This safety applies to chillers with 031-01652-001 (CRCP Version) EPROMs, I/O Expansion Boards, and Oil Temp Sensors.
Содержание YCRJ45E00
Страница 29: ...FORM 150 24 NM27 YORK INTERNATIONAL 29 CONTROL CIRCUIT With I O Expansion Board LD02106 ...
Страница 30: ...30 YORK INTERNATIONAL FIG 9 SYSTEM WIRING ...
Страница 31: ...FORM 150 24 NM27 YORK INTERNATIONAL 31 LD02678 ...
Страница 33: ...FORM 150 24 NM27 YORK INTERNATIONAL 33 LD02357 MOTOR TERMINAL BOX WIRING WITH MODEL 31AA MOTOR PROTECTOR ...
Страница 34: ...34 YORK INTERNATIONAL FIG 10 CONNECTION DIAGRAM LD02358 MICROPANEL CONNECTION DIAGRAM WITHOUT EXPANSION BOARD ...
Страница 35: ...FORM 150 24 NM27 YORK INTERNATIONAL 35 LD02679 ...
Страница 36: ...36 YORK INTERNATIONAL MICROPANEL CONNECTION DIAGRAM With I O Expansion Board LD02107 ...
Страница 37: ...FORM 150 24 NM27 YORK INTERNATIONAL 37 LD02108 ...