Advantage OACS Series, Инструкция по эксплуатации

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OACS Central Chillers : with MG Series Control Instrument
Page: 25
ADVANTAGE ENGINEERING, INC.
525 East Stop 18 Road Greenwood, Indiana 46142
317-887-0729 Fax: 317-881-1277
Service Department Fax: 317-885-8683
Email: service@AdvantageEngineering.com
shaft. Correct rotation (correct phase)
is “clockwise”, when viewed from the
rear of the motor. Incorrect rotation is
“counter-clockwise” (incorrect phase)
when viewed from the rear of the
motor. If the shaft does not rotate
when the ON/OFF SWITCH is on, the
operator must identify the cause as
outlined in the troubleshooting and
repair section of this manual.
f. If the motor shaft is phased correctly
(shaft turns in a clockwise direction), continue with step C. If the motor
shaft is NOT phased correctly (shaft turns in a counter-clockwise
direction), correct as outlined in step 2.
2. If the unit is phased incorrectly, the operator must:
a. Disengage the electrical power supply to the unit at the unit’s disconnect
switch. Follow all facility proper lock-out tag-out procedures before
proceeding.
b. Once the electrical power supply is disengaged the operator can change
rotation by switching any two power conductors at the terminal block or
customer supplied main power disconnect.
C. PROCESS FLOW ADJUSTMENTS
1. The operator must determine and set proper water flow rate for the most efficient
and trouble free operation.
a. Water flow rate through the process is determined by the pressure losses
in the process loop. Generally, higher flow rates result in turbulent flow
achieving maximum temperature control and lower maintenance. Since
the evaporator in most liquid chillers is flow sensitive, the efficiency of
operation is directly related to the flow of liquid.
b. Maximum chiller efficiency is obtained at approximately 2.4 gpm per
ton of rated capacity. Low liquid flow can reduce efficiency and in some
cases allow ice to develop in the evaporator which can damage the
evaporator. Excessive liquid flow will trip the motor overload protection
circuit.
2. Excessive flow will cause the motor to operate at high amperage and
eventually open the thermal overload safety shutting off the motor. Motor
amperage rating may be acquired on the motor nameplate.
3. Low flow may result in poor temperature control and high temperature
rises. To correct this problem, a bypass system must be installed between the to
and from process lines. With the bypass valve fully closed, slowly open the valve
until the correct motor amperage is achieved. Motor amperage rating may be
acquired on the motor nameplate.
Correct shaft rotation is clockwise.