Large
Portable

Load Cube
2500KW

Load Cube
Portable Load Bank

The Simplex Load Cube is an ultra-large capacity, fully portable, resistive/reactive Load Bank System intended for field use in testing, maintenance and performance proving of large generating systems. The Load Cube is rated 2500KW, 1875KVAR at 400-600V commercial AC voltages. The Load Cube is typically used to test large diesel generators, turbines, paralleled generators and shipboard generators.

With a purpose-built design consisting of rugged, all-welded, tubular steel frame, heavy gauge steel sides, guarded hinged doors, power-operated ventilation louvers, the Load Cube is far superior to designs which use refurbished and modified ISO shipping containers. Four-sided access allows ready service of all components and facilitates the ultra-compact design.

Compact and easily transportable, the Load Cube is ideal for rental use. With a footprint of only 8 x 10 feet and a height of less than 9 feet, the Load Cube is easily transportable by conventional-height flat bed trailer. Lifting eyes and forklift channels simplify site movement.

The Load Cube utilizes digital load control for direct access of load values, block transitions, and user programmable automation. A selection of digital power meters and data acquisition software is available.

The Simplex Load Cube represents the ultimate technology in large generator load testing performance.



Load Elements

Simplex Powr-Web:
Open wire, helically wound, chromium alloy, load element thermally derated to 60%. 5% tolerance, 2% balance. .995 p.f. Element wire mechanically supported over entire length such that if a wire should break, the broken wire segments will not short to adjacent conductors or to ground. Load elements are individually serviceable and replaceable in the field without major disassembly of the load bank. The load elements are installed in slide-out, removable trays such that any element is easily accessed without disturbing any other elements.

All materials used in the mounting and installation of the load elements are suitable for the temperatures encountered, in both normal operation and under fault conditions.Materials in direct contact with the element wire are ceramic. Other materials which structurally support the load elements and/or which form the hot air duct within which the elements are mounted are steel, stainless steel or aluminum. Plastics and glass reinforced plastic materials and flammable materials are not used for installation, support and mounting of load elements or in the construction of the load bank hot air duct.

Inductive Elements:
Non-saturable, air-gap type, iron-core power inductors. 5% tolerance, 1% waveform distortion, 0.05 power factor, 150°C rise, 220°C insulation.

Simplex Load Banks can be used to satisfy the requirements of the National Fire Protection Association (NFPA) for emergency stand-by power systems.

Powr-Web Load Element

Simplex Load Banks utilize the UL Recognized, “Powr-Web” load element. The “Powr-Web” is an advanced design, air-cooled power resistor specifically designed for application to load bank systems. The “Powr-Web” is conservatively operated at half the maximum temperature rating of the alloy and features a short-circuit-safe design based on continuous mechanical support of the resistor by high temperature, ceramic clad stainless steel rods. The “Power Webs” are assembled into discrete trays which are assembled in a vertical “stack.” Each tray in the “stack” is independently serviceable without disturbing adjacent trays.

Ratings
3333W at 120V
4170W at 139V
8333 watt 240/480V
16,777 watt at 480V

Specifications
Alloy: FeCrAl
Max. continuous temp. rating: 1920°F
Maximum operating temperature as applied in Load Bank: 1080° F
Cool down time from operating to ambient temperature: 10 seconds

Construction
Calibrated to specific ohm value
Welded lugs on each end
All load elements are continuously supported by vibration resistant, ceramic clad, stainless steel throughrods
 

Inductive Load Elements

These discrete iron-core load elements are non-saturable, air gap calibrated, air cooled devices and field replaceable. Elements may have a temperature sensor embedded in the windings used to detect element overheating and activate the malfunction detection system which disconnects the load elements and activates an alarm. Standard elements are varnish coated; epoxy coatings are available for severe environments.

Specifications
Tolerance: 5%
Maximum Harmonic Distortion: 1%
Power Factor: .05
Insulation: 220°C
Cooling: Air

 

Branch Circuit Fuse Protection

The load of a Resistive Load Bank consists of a dense array of open, uninsulated power resistors mounted within a cooling air stream. Since the elements are electrically live, it is possible for a foreign object to penetrate the element array and create a short circuit of adjacent elements or a short to ground. Since the elements are densely packed, it is possible for a short circuit, once started, to rapidly propagate through the entire element array. As a Load Bank represents a relatively large amount of power concentrated within a relatively small volume, a self-propagating, cascading short circuit would have catastrophic results.

Simplex virtually eliminates the dangers of short circuit through the use of branch circuit fuse protection of the load elements. Per NEC 110-10, protective devices shall clear a fault without “extensive damage” to the circuit components. A Simplex Load Bank is divided into branch circuits of not more than 50 KW each.