Compact Motor Soft Starter adapts to application needs.

Press Release Summary:

Available in 23 models and 5 frame sizes from 21-1,600 A, VLT® Soft Starter MCD500 features Adaptive Acceleration Control that lets users select different acceleration and deceleration profiles according to application needs. Product pulses DC over all 3 phases and does not require external contactor for stopping. Emergency Run Mode enables motor to run continuously despite deteriorating environment, while second order thermal model supports full motor operation without overload damage.

Original Press Release:

New VLT® Soft Starter MCD500 Adapts Acceleration and Deceleration Profiles Based on Specific Application Needs

Adaptive Acceleration Control "learns" motor performance during start and stop functions to adjust control for optimized performance

MILWAUKEE, WI - Danfoss Drives introduces the VLT® Soft Starter MCD500 with Adaptive Acceleration Control (AAC). AAC is the newest evolution in soft start technology, enabling users to select different acceleration and deceleration profiles according to specific application needs, optimizing performance and maximizing energy efficiency.

Among the most compact soft starters available in its class, the features-laden VLT Soft Starter MCD500 is available in 23 models and five different frame sizes, from 21A - 1600A (7.5kW - 800kW). The G1 frame size is IP20 rated, and G2 - G5 frame sizes are IP00 rated. Optional finger guard kits are available for the G2-G5 frames to achieve IP20. Moreover, the MCD500 is significantly smaller and more compact than its MCD3000 predecessor. The MCD 500 series have earned certification and approvals by the following: CE, CCC, C-Tick, RoHs, UL, cUL and Lloyds Register.

"Using AAC, the soft starter learns the motor's performance during start and stop, then adjusts control to optimize performance. AAC control adapts itself to the motors profile, making for more efficient and precise control of the motor. This benefits the user by being able to match the soft starter and the motor as a coordinated system," says Doug Yates, Product Manager for Danfoss Drives.

Soft Starters are typically used to limit motor start current, or to control load acceleration and /or deceleration. The former is best accomplished with constant current control, and the latter is best accomplished with Adaptive Acceleration Control. The MCD 500 offers both constant current and Adaptive Acceleration Control, making it a powerful and flexible soft starter solution ideal for any number of water/wastewater, HVAC, industrial, and food and beverage applications, among others.

Soft starting, or gradual and shock free acceleration, can benefit all motor applications, but many situations need more precise acceleration and /or deceleration control - that is where AAC technology shines. For example, AAC is particularly dominant in controlling pumps, band saws and conveyor systems because it allows the selection of multiple deceleration profiles.

"Consider pumping High Head in a water tower application. Here, constant current control methods can be problematic because of the high back pressure, which can mean that even a small variation in speed can result in water flow switching rapidly from forward to reverse. This rapid change in water flow results in significant reverse flow, causing the non-return valve to slam shut sending damaging shock waves (water hammer) throughout the system. AAC is an ideal solution because its late deceleration profile will prevent water hammering by providing slow ramp-down while the valve closes," says Yates.

The VLT Soft Starter MCD500 is loaded with additional features to satisfy various application needs and optimize performance, including:

o Integral bypass contactor for models up to 215 Amp or 150 Hp - this reduces space requirements and eliminates the need for external equipment, and simplifies installation.

o MCD communication options to support the following field bus networks: ASCII for Remote Operator and WinMaster, Profibus DP, DeviceNet and Modbus RTU and USB option.

o User friendly 4-line plain language and graphical display; supports eight languages, including Chinese.

o A simulation function lets users test the external control circuits and equipment without connecting the MCD500 to line voltage or a motor.

o MCD500 models of 360A and above have adjustable bus bars that allow top or bottom connectivity of input and output cabling; this also provides flexibility in retrofitting other starters where the bus bars or cables are located top or bottom.

o Stopping - The MCD500 pulses DC over all three phases, and does not require an external contactor. The majority of competitive soft starters pulse DC in only two phases, and require an external contactor.

o The MCD 500 slow speed, or JOG, function allows the operator to run the motor at part speed in either forward or reverse direction; this is ideal for load positioning in mixers or hopper bins ready for unloading.

o Activation of the MCD 500 Emergency Run Mode initiates a start and deactivates all protection systems, which enables the motor to run as long as possible despite a deteriorating environment. For example, in case of a fire, equipment such as ventilation fans in high rise buildings can be required to run at all costs.

o Premium overload protection - The MCD 500 "second order thermal" model allows motors to be used to their full potential without fear of damage from overloading. The second order thermal model takes into consideration the difference between the motor winding and motor casing characteristics. It also accounts for motor current, iron losses and winding resistance losses, and even accounts for running the cooling fan at the back of the motor versus standstill. This feature enables users to avoid having to use expensive motor protection relays.

Danfoss is a leading manufacturer of precision mechanical and electrical components, with locations in more than 120 countries. In addition to setting the standard for high-performance quality variable frequency drives, Danfoss meets the needs of its customers through its EnVisioneeringSM partnerships. EnVisioneering focuses on developing new technologies for sustainable business growth through engineering innovation, energy efficiency and environmental responsibility.

Danfoss Drives, 8800 W. Bradley Road, Milwaukee, WI 53224; (800) 621-8806; Fax: (414) 355-6117;;

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