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FORM 201.10-NM1
109
YORK INTERNATIONAL
NOTE: Do not confuse FLA and RLA. FLA (full load
amps) is approximately 1.2 x RLA. RLA (running
load amps) specified on the motor / chiller 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 a fully loaded condi-
tion, expect motor currents to run 65 - 85% FLA.
Six internal sensors are built into the motor (3 on each
end). These sensors are wired into the Motor Protector
Module located inside the Motor Terminal Box. As the
windings heat and cool, the resistance of the motor tem-
perature sensors will change. If the windings overheat,
the change in resistance in the sensors will be sensed
by the Motor Protector Module. The module will open its
MP contacts breaking the 115VAC fed to the 1CR (Sys
1) or 2CR (Sys 2) control relay.When a control relay is
de-energized, power is removed from the compressor
contactor which shuts the compressor off. When the motor
contactor de-energizes, motor current falls to zero. The
low motor current is sensed by the microprocessor and
the system is shut down.
Auto-restart will not be permitted after shutdown or a
motor protector module trip. The motor sensors must
cool and control power must be removed from the
control panel to reset the MP contacts. A fault lockout
will automatically occur after the micro attempts 2 more
starts with the MP contacts open.
Each compressor is protected by an External Motor Over-
load (OL) Relay responsive to motor current. When the
overload relay senses single phase operation, locked rotor
current in excess of 10 seconds, or sustained current
overloads in excess of 140% of RLA, the device will trip.
This opens the 1 OL (Sys 1) or 2 OL (Sys 2) contacts
which de-energizes 1CR (Sys 1) or 2CR (Sys 2) control
relay. When a control relay de-energizes, power is re-
moved from the compressor contactors which shuts the
compressor off. When the motor contactor de-energizes,
motor current falls to zero. The low motor current is sensed
by the microprocessor and the system is shut down.
The OL relay setting should never be altered. If for some
reason the Overload Relay is replaced, the following pro-
cedure is used for set-up.
A/L Start:
C.T’s sense total compressor current so
OL Relay Dial Setting =
(1.1 x RLA)
350
WYE-Delta Start:
C.T.’s sense 58% of total compressor current so
Relay Dial Setting
=
(1.1 x 0.58 x RLA)
350
Anytime the External Motor Overload Relay trips, a
manual reset of the device is required to restart the com-
pressor. After the first fault, the micro will try two more
restarts, but with the External Motor Overload Relay
tripped, no restart can occur. The micro will then lock out
the system. In addition to manually resetting the Exter-
nal Motor Overload Relay, the fault will also require reset
by turning the system switch of problem system off.
Assure that the cause of the fault is determined before
returning the system to service.
The HP (High Pressure) Cut-out will also cause the low
current safety to activate. If discharge pressure exceeds
405 PSIG (HP Cut-out), the cut-out will open. When the
cut-out opens, 115VAC power will be removed from the
Motor Protector Module. When power is removed from
the module, its MP contacts will open, breaking the
115VAC fed to the 1CR (Sys 1) or 2CR (Sys 2) control
relay. When a control relay is de-energized, power is re-
moved from the compressor contactors which shuts the
compressor off. When the motor contactor de-energizes,
motor current falls to zero. The low motor current is sensed
by the microprocessor and the system is shut down.
Auto-restart will be permitted after shutdown, when dis-
charge pressure drops below 330 PSIG and the HP con-
tacts close. A fault lock-out will result if safety thresh-
olds are exceeded three times in a 90 minute period.
Motor Current Unbalance Safety
The Motor Current Unbalance Safety assures that cur-
rent balance between each of the three phases is within
an acceptable limit. This provided further motor protec-
tion by preventing operation which could overheat one
winding causing damage to the motor. It also provides an
early warning of problems such as contactor contact wear,
loose power wiring connections, and voltage problems in
building power sources. This safety is an alternative and
an enhancement to the internal thermal protection already
provided by the motor protector.
After 1 second of operation, the current of any phase
must be or - 40% of the average current of the
three phases. Exceeding these limits for greater than 3
seconds will cause the compressor to shut down.
An example of the Motor Current Unbalance Fault mes-
sage is shown below:
High Oil Temperature Safety
This safety assures that oil temperature does not ex-
ceed a safe operating temperature due to a system prob-
lem in the oil cooling circuit which could cause damage
S Y S
1
M T R
C U R R
U N B A L
S Y S
2
M T R
C U R R
U N B A L
Содержание Millennium YCAS 316
Страница 11: ...FORM 201 10 NM1 11 YORK INTERNATIONAL YCAS 140 246 DIMENSIONS English LD01444 LD01446...
Страница 13: ...FORM 201 10 NM1 13 YORK INTERNATIONAL YCAS 140 246 DIMENSIONS SI LD01440 LD01442...
Страница 15: ...FORM 201 10 NM1 15 YORK INTERNATIONAL YCAS 216X 266X DIMENSIONS English LD01454 LD01454...
Страница 17: ...FORM 201 10 NM1 17 YORK INTERNATIONAL YCAS 216X 266X DIMENSIONS SI LD01450 LD01448...
Страница 33: ...FORM 201 10 NM1 33 YORK INTERNATIONAL 28514A FILTER DRYER LIQUID STOP VALVE...
Страница 37: ...FORM 201 10 NM1 37 YORK INTERNATIONAL LD01285 FIG 3 SCREW CHILLER REFIGERANT FLOW DIAGRAM...
Страница 54: ...54 YORK INTERNATIONAL FIG 9 SYSTEM WIRING YCAS 140 246 CONNECTION DIAGRAM SYSTEM WIRING LD01466 D...
Страница 59: ...FORM 201 10 NM1 59 YORK INTERNATIONAL FIG 11 CONTINUED LD01465 D...
Страница 60: ...60 YORK INTERNATIONAL FIG 12 CONNECTION DIAGRAM WYE DELTA YCAS 140 246 CONNECTION DIAGRAM WYE DELTA LD01458 D...
Страница 61: ...FORM 201 10 NM1 61 YORK INTERNATIONAL FIG 12 CONTINUED LD01458 D...
Страница 69: ...FORM 201 10 NM1 69 YORK INTERNATIONAL FIG 16 CONTINUED LD01206 D...
Страница 71: ...FORM 201 10 NM1 71 YORK INTERNATIONAL FIG 17 CONTINUED LD01202 D...