Part 1 of this article series looks at what to consider when selecting motor connection cables, output reactors, braking resistors, line reactors and line filters. Part 2 continues by looking at the differences between VSDs/VFDs and servo drives, reviewing uses for AC and DC rotary and linear servo motors, considering where soft start-stop units fit into industrial operations, and Looking at how DC converters are used to power peripherals like sensors, human-machine interfaces (HMIs), and safety devices. Using variable speed drives and variable frequency drives (VSDs/ VFDs) is necessary to maximize industrial operations' efficiency and sustainability, but it’s not sufficient. To get the maximum benefit from VSDs/VFDs, additional components like high-performance cables, braking resistors, line filters, line reactors, output reactors, and more are needed. Cabling is ubiquitous and critical. A poorly specified cable connecting the VSD/VFD to the motor can significantly degrade system performance. Other elements like braking resistors, filters, and reactors vary from installation to installation and can be very important to a successful deployment. For example, some systems operate in areas where it’s necessary to control electromagnetic interference (EMI) and can benefit from using line filters that meet EN 61800-3 Category C2. Applications where rapid deceleration is required will need braking resistors. Line reactors can
improve the power factor and boost efficiency, and output reactors can enable the use of longer cables. This article begins with a look at some considerations when selecting motor connection cables and presents typical cabling options from LAPP and Belden. It then reviews factors that impact the selection of output reactors, braking resistors, line reactors, and line filters, including representative devices from ABB, Schneider Electric, Omron, Delta Electronics, Panasonic, and Siemens. Motor cables are available in various configurations to meet specific application requirements. They typically have three main power conductors, often insulated with cross-linked polyethylene
(XLPE). Some have uninsulated grounding wires. There can be various signal wires and numerous braided and foil shielding choices. The entire assembly is encased in an environmentally rugged outer jacket (Figure 1). Even basic cables like Belden Basics part number 29521C 0105000 are complex assemblies of conductors, shielding, and insulation. These cables have three 14 American Wire Gauge (AWG) (7x22 strands) copper conductors covered with XLPE insulation and three 18 AWG (7x26 strands) uninsulated copper ground wires. These six wires are surrounded by dual helical tape shields that provide 100% coverage, and the
Figure 1: VFD motor cables come in a wide range of configurations. (Image source: Belden)
we get technical
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