Lenze explains how to choose, install and commission a drive.

The difference between soft-starters and VFDs

Eaton's new C441 Ethernet series of communications cards allow customers to select from Ethernet/IP, Modbus TCP, HTTP web services and Modbus RTU communication protocols in a single card. The innovation is designed to help industrial customers, machinery OEMs and panel builders with flexible communication options to configure, control and monitor their systems.

Integral web services provide an easy-to-use web-based graphical user interface (GUI) to make it easier to recognize potential problems. Using a laptop or smart device, customers can drill down to a given load by simply entering an IP address into their web browser. With four levels of access, the cards ensure only those with credentials have access to critical or sensitive functions.

An Eaton representative explained, “Integral web services allow for configuration, control, monitoring and diagnostics. Also, the flexibility in communications allows OEM customers to add value to their equipment with simple and desirable features, like supervision and control.”

The C441 is compatible with Eaton C440, XTOE and C441 electronic motor protection relays, S611 soft starters, and can be used as stand-alone input/output (IO). Now, the suite of protocols available for Eaton motor protection and soft starter solutions includes PROFIBUS, Modbus TCP and RTU, DeviceNet, and Ethernet IP.

Problems can be addressed in real time with intelligent monitoring readouts from starters and onboard available four digital inputs (120 volts alternating current or 24 volts direct current) and two discrete relay outputs. With a dual port switch, the Ethernet card allows for easy daisy chaining and reliable ring configurations. Additionally, customers have the ability to use one network for control and another for monitoring – through the Modbus serial protocol used in parallel with the Ethernet network –allowing redundant communications and greater reliability with a single card.

According to a recent report from IMS Research, pumping applications account for the majority of the global medium voltage motor control centers market. From an industry perspective, this market is heavily concentrated in the oil & gas and mining sectors, which account for more than half of total revenues in 2010. Other notable industries in this market included chemicals, commercial HVAC, power generation, pulp & paper and water & waste-water. Together, these sectors contributed another 26% of market revenues during the year. Highest growth forecasts are projected for the oil & gas and mining segments of this market from 2010 to 2015, largely due to high commodity prices that are expected to persist.

The global market for medium voltage motor control centers was worth more than $140 million in 2010, with more than 5,300 units shipped during the year. It was a recovery year following a dismal 2009, albeit as slow one. The US market comprised more than 60% of the global market during the year, while Canada accounted for nearly 20% of total revenues. The markets in EMEA and in Asia Pacific were much smaller, together comprising only 13% of total market revenues in 2010.

The main reason for the market’s concentration in North America stems from the fact that US end-users have a different approach to systems engineering. In the US, for example, much of the engineering expertise at many OEMs and end-users continues to be downsized, and companies increasingly rely on system engineering services from some of the larger industrial automation suppliers such as ABB, Eaton, Rockwell Automation, Schneider Electric and Siemens, who carry-in their own MCC solutions.

Outside of the US, the most common approach to starting and stopping medium voltage motors is to use vacuum breaker based medium voltage switchgear, normally designed and installed by a systems integrator, not one of the larger automation suppliers.

Eaton has announced a new family of soft start controllers available for current ranges from 16 to 32 amps. An asymmetric delay angle control helps make torque behavior similar to a three-phase starter. The DS7 series can take 24 volts (V) of direct or alternating current, or 110V/230V of alternating control voltage. It is also Underwriters Laboratories (UL) approved.

From the release: "Designed for pump, fan and conveyor belt applications, as well as water/wastewater and heating, ventilating and air conditioning (HVAC) industries, the DS7 soft starters reduce the demands made on a motor during start up, resulting in reduced energy requirements."