Technical Specifications

8/2012-Rev A (LCV)
2.2 MATERIAL AND CONSTRUCTION
A. The load bank shall be outdoor construction housed in 40' ISO style container (tall cube 9'-6")
with vertical air flow suitable for permanent operation.
B. The ISO style load bank container shall be fabricated from formed and welded steel, making a
rigid, drip-proof structure. The container shall be primed on the inside and out with catalyzed
epoxy primer and catalyst. Finish shall be two coats of ANSI 61 Gray urethane, Polane S. Total
dry film thickness to be 4.8-6.2 milage less spatter top coat if applied.
C. Primary load connection will be to copper load bus bars housed in a recessed lockable
compartment (external access).
D. The main medium voltage input load bus and medium voltage vacuum load contactors, shall be
located within a dedicated local load bank enclosure.
E. An integral low voltage enclosure shall be provided to house control devices, fuses, fan
starter/control relays and safety circuits. Thermostatically controlled heaters shall be located
within the control section to provide protection to the control devices from the effects of low
temperature, moisture and condensation.
F. Airflow through the load bank resistor section shall be vertical. Ambient intake cooling air shall be
drawn in at the bottom of the unit and heated air exhausted out the top. Intake openings shall be
designed to prevent objects greater than 12mm (0.50") diameter from entering the unit.
G. The load bank exhaust hoods shall be angled and include interior baffle plates to direct falling rain
from the interior of the load bank.
H. Load elements shall be contained in multiple resistor cases or trays. Each can be removed in it’s
entirety as a unit for inspection or service.
2.3 RESISTIVE LOAD ELEMENTS
A. Load elements shall be Avtron Helidyne™, helically open wound nickel/chromium alloy,
rated to operate at approximately half of maximum continuous temperature rating of wire.
Elements must be fully supported across the entire length within the air stream by
segmented ceramic insulators on stainless steel rods. Materials in direct contact with
resistors shall be ceramic. Element supports shall be designed to prevent a short circuit to
adjacent elements or to ground.
B. The change in resistance due to temperature shall be minimized by maintaining conservative
watt densities.
C. The overall tolerance of the load bank shall be –0% to +5% KW at rated voltage. A –5%,
+5% rating allows the load bank to deliver less than rated KW and shall not be used. The
load bank must deliver full rated KW at rated voltage.
2.4 COOLING
A. The load bank shall be cooled by integral TEFC or TEAO motors which are direct coupled to
the cooling fan blade. Each fan motor must be electrically protected against overload using a
motor overload device and short circuit protected using three (3) current limiting fuses with
an interrupting rating of 200K A.I.C.
B. The fan blade is to be an airfoil design constructed from aluminum or non-corroding material.