A02_Medium_Load_Bank_Specification.docx

Equipment Design Requirements:

LOAD BANK:

10ft Containerized Load Bank Type MC1C-3125 Combined Resistive/Inductive Rated: 3125kVA @ 0.8pf 480V 3ph 50/60Hz Continuous Duty Rated Comprising: 2500kW* at 480V 3ph 60Hz 1875kVAr at 480V 3ph 60Hz Fully variable power factor capability 1kW or 1kVA nominal load step Fan Motor & Control Circuit Dual 50/60Hz 380-420V 3ph; 440-480 3ph 60Hz

ISO Style containerized construction. Vertical discharge.

Walk-in control room for easy access to control, switchgear and optional power circuit breakers Air inlet covers provide protection from dirt and moisture during transport Polycarbonate screens in control and switchgear enclosures protect all live parts from accidental contact Four Lift Frame: Quantity Four (4) integral lifting holes plus Fork Pockets Built into Container Base

Load Control – Sigma IHT3 (v4) with instrumentation and a standard 10m Lead:

The system will use a Sigma 'Intelligent Handheld Terminal’ IHT3, with full instrumentation that will be connected to the load bank with a standard 10m reinforced multi-core cable fitted with quick release plug and socket connectors.

Also a Sigma Extension Lead (100m) supplied on Reel

HMI touch screen module Multi-functional display, located inside the control room area.

It will consist of a local load selection and activation, measured power, selected power Diagnostic display down to component level.

It will consist a Sigma PC Load Control Software v2 with USB Interface.

The Sigma PC load control system software, will replace the standard IHT for control of the load bank. The Sigma PC load control system will provide enhanced load control and full data acquisition capabilities.

Construction:

The frame of the load bank will be constructed from 2mm ‘Zintec’ steel, folded and welded to form a monocoque construction. Double skinned recessed doors allow easy access to the separate enclosures for control, switch gear and power connections. The double skinned, horizontal discharge duct with stainless steel heat shield contains the resistive load elements and the cooling fan. Stainless steel mesh screens on the main air inlet and outlet provide protection against access to hazardous parts to IP1X. All electrical enclosures are to IP54. High quality two-pack industrial acrylic paint system applied to an electro-plated zinc base and low-bake finish.

Paint Finish: The container will be Brown Beige RAL1011.

Load Connections:

Load Bank will have Cam-Lock type connectors for load connection on the outside of the Load Bank enclosure.

Load Elements:

Froment load banks will use replaceable, non-finned sheathed elements. The outer sheath will made from stainless steel to give good corrosion resistance. The heating element will be an 80/20 nickel-chrome wire embedded in compacted magnesium oxide powder, giving good thermal and insulation properties. These elements are very conservatively rated and there is no need for cooling fins to dissipate the heat into the airflow. This will ensure that foreign matter or a loosely fitting fin cannot possibly cause hot spots and therefore ensures high reliability.

The elements will be designed to operate continuously at up to 800°C (red/orange). The actual temperature will be below 500°C (dull red). This will give a wide margin of safety and very long life. Load tolerance will be within 2½ % of total capacity. Elements will be continuously rated at the specific voltage. Short-term tests with fluctuations up to 10% above rated voltage will be permissible. Tests at lower voltages, with a corresponding reduction in overall rating, may be carried out. Power is proportional to voltage squared.

Auxiliary Power:

The fan and control circuit may be powered from an external auxiliary supply or from the supply on test, provided it is of the correct voltage and frequency. Lower voltages and other frequencies must be tested using the external supply. On static load banks, connection is by internal terminals. On movable load banks, an IEC 60309-2 plug and socket with a three-position switch enables quick and easy connection. Dual 50/60Hz Fan & Control Circuit: 380/420V, 50Hz and 440/480V, 60Hz.

Safety Features:

• An emergency stop/disconnect switch that gives full isolation of the fan and control supply.

• A 110 Volt AC control circuit transformer that provides isolation and operator safety.

• Stop/start buttons ensure that the load bank will not automatically restart. When a static load bank, a provision is made for the connection of remote stop/start buttons.

• The fan motor must be fully protected with fuses and a thermal overload. Movable load banks will also be fitted with phase rotation detection to automatically ensure correct airflow direction. Single phasing protection will be provided by the overload. Thermal detectors will be fitted to protect against overheating in the resistive duct and switchgear enclosure.

• Over voltage protection for the control and load circuit will be provided by Sigma load control.

• Each element group and its associated contactor will be protected by an HRC fuse. This is very important when testing large capacity power supplies, due to the possible high fault currents.

• The load contactors will be interlocked with the fan controls to ensure load can be applied only when the fan is running.

• Internal access will be restricted by key operated door catches. Polycarbonate screens behind the doors will prevent accidental contact with live parts.

Airflow and Noise Level:

Forced-air cooling is by a single axial metal-bladed airfoil fan, giving vertical discharge. Typical noise level will be less than 90dBA at 60Hz. Measurements will be taken 3 meters from the load bank and at 90º to the airflow direction. Noise readings are subject to a tolerance of ±3dBA.

Testing, Standards and Warranty:

Functional operation and load tests are completed on all load bank, before dispatch, in line with ISO 9001:2008 procedures. Froment load banks will comply with international standards and will be CE marked to confirm compliance with both the EMC and Low Voltage Directives.

Dimensions and Weight (approximate):

Height: 8.5’ Width: 8.0’, Length: 10.0’ Weight: 18,750 lbs.

TRANSFORMER:

3400kVA, dry type, Aluminum wound, VPI, special with load break (medium voltage quick-connect), 4160:480V, 3- phase, 60Hz, 150C rise, 120” long, 96” deep, 102” high, 14,000 pounds.

SEMI-TRAILER & INTERCONNECT:

Trailer for transformer and load bank, drop deck, air ride, 40-foot overall length, semi-trailer. Semi-trailer would be 102” wide, 41” high (loaded height to lower deck), 40’ long (29’ lower drop deck). It will include mounting for load bank and transformer, air brakes including ABS, air suspension, two speed front landing gear, dual axle, standard semi-trailer air hook ups, and electrical 7-way plug. Primed and finish painted black.

SKID & INTERCONNECT:

Load bank and transformer will be mounted and interconnect on a common steel skid. Skid would be 318” long, 100” wide and 16” deep. Approximate weight, with transformer, load bank, skid and interconnect, will be 40,000 pounds. This will require a double drop to ship. No fork lift, overhead lift via end cross tubes only.

NOTES:

1) Equipment de-rates at 3800/3/50

2) SIGMA does not monitor transformer losses.

MANUALS:

Manuals for the load banks, transformers and trailer with interconnect will be provided. Also wiring diagrams, interconnect diagrams and schematics will be provided.