Merlin

Features

Load Element

• Simplex Powr-Web chromium alloy, open wire, continuously supported, power resistor.

Load Elements

• Simplex Load Banks utilize UL rated, industry leading "Powr-Web" load elements specifically designed for load banks.


• The "Powr-Web" elements are 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.


• "Powr-Webs" are assembled into discrete trays which are inserted into a vertical "stack." Each tray in the "stack" is independently serviceable without disturbing adjacent trays.

Ratings (typical)

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

All load elements are continuously supported by vibration resistant, ceramic clad, stainless steel through-rods.

System Controls

• Digital Meter (100KW-400KW).
• Fan Reversal, Load Voltage Selector, and Control Voltage Selector switches.
• Operator indicator lights: normal operation, over-voltage, fan failure / over-temperature.
• Master load toggle switch and load step toggle switches.

Cooling

• 3-phase, direct drive fan, 6,000-8,000CFM (depending on load configuration).
• Casts aluminum air foil type, shrouder propeller fan.
• Horizontal airflow - cold air intake from front, hot air exhaust out the rear.

System Protections

• Sensors, alarms (alarm message on remote operator interface terminal), lockouts as appropriate, for the following: fan failure, high exhaust temperature, high intake temperature, high interior temperature (sensed at three points).
• Load Circuit Protection: branch circuit fuses. One set of fuses each 50KW branch. Fuses are current limiting type, 200,000 AIC, 600V, enabling safe use on large generating or UPS system.

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.

Load Control

• Master load toggle switch and load step toggle switches.
• 3-pole magnetic contactors.

Power

• Operator selectable fan/control power-source:
  • Internal Power: fan and control circuits powered internally, does not require external power.
  • External Power: fan and control circuits powered from external 3-phase outlet or other external source.

Connections

• Control Wiring: 105°C, color coded.
• Power Wiring: 150°C XLP color-coded.

Load Connection

• 100KW-400KW: 12' connection cable set including 3-phase power cables, ground cable and external control power cord.
• 500KW: cam-type connectors and external control power cord.

Enclosure

• Exceptionally rugged, all welded, formed steel chassis.
• Portability features: lifting eyes, forklift channels, casters and moving handle.

Technical Documents

• Merlin 100KW, 150KW Load Bank - Pictorial Drawing
• Merlin 200KW-300KW Load Bank - Pictorial Drawing
• Merlin 350KW-400KW Load Bank - Pictorial Drawing
• Merlin - Product Brochure
• Merlin 500 - Product Brochure
• Merlin 100KW-400KW Load Bank - Dimensions & Key Features

Options

• Cam-type power connections (standard for 500KW)
• Vinyl cover