Avtron K922A, Руководство пользователя

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Introduction and General Description
Avtron Outdoor Resistive Load Bank • Part Number K922AD41523
2-2
blocks for wiring the safety components, enclosure heater, and the input control and fan power
terminal blocks. Located within the medium voltage area are the three main load connection bus
bars, CTs, PTs, configuration panel, load step contactors, a ground bus bar, and enclosure heater.
Load connections are made through center access door on side of unit. Configuration panel is on the
other side.
The Load Bank is equipped with vertical gravity exhaust hatches fabricated from unpainted stainless
steel. These are mounted to the top of the frame above each resistor stack. The hatches are designed
to open when fans are energized and close by gravity to minimize the effects of rain and snow, and
to prevent foreign objects from entering the Load Bank.
NOTE
Prior to operation, the hatch retaining clip must be unbolted from
each set. Replace retaining clip prior to transport and during storage.
The Load Bank is designed to be lifted from overhead using the four roof cleats welded to the frame
and an appropriate lifting/hoisting device. Refer to the INSTALLATION section of this manual.
Bolt holes are provided in the legs of the unit for permanent pad mounting via elevated frame
extension legs. Installation should provide minimum 30 inches clearance from bottom of fan intake
to any surface. The dimensions of the Load Bank including the exhaust hatches are 310.00 inches
long x 102 inches wide x 119.00 inches high (less extension legs), and weight is approximately
18,000 lb. (Ref. SB3671.)
The K922AD41523 Load Bank contains eight tube axial fans with eight 3-phase, 460 VAC, 60 Hz,
10 H.P., 1725 RPM fan motors, which provide the necessary cooling air for the load elements. Each
fan assembly has been designed to provide approximately 16,000 scfm at 1.7 inches of static
pressure. These motors have special bearing lubrication and embedded heaters within the motors for
special low temperature service. The fan motors are controlled by motor starter relays K1-K8. Short
circuit protection is provided by fuses F1-F24, which are dual-element, time delay, Class J, 20 amp
fuses. Overcurrent protection is provided by these fuses and overload relays.
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C A U T I O N
The Load Bank should never be used without all of the fan motors
operating. Inadequate cooling airflow will result in resistor elements
overheating and a fire hazard.
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