Line reactors are widely used for stabilizing and smoothing the current waveform and protection of variable frequency drives (VFDs). They also assist in reducing the burden on upstream electrical components. Information about what they do and how they do it is in abundance on the Internet but we rarely encounter the details of their installation.
Nevertheless, installing them is an indispensable part of the industry. Therefore, in this post, we will discuss with you what you should know while Installing Line Reactor on the Input Side of the Variable Frequency Drive. So, without any delay, let’s check it out.
- A line reactor is a three-phase device. It is connected in a series configuration and installed on the input side of the VFD. The reactors which are installed on the output side of the VFDs are particularly called load reactors instead of line reactors.
- Let’s assume the input terminals are A1, B1, and C1 where three phases of incoming power are to be wired and A2, B2, and C2 are the output terminals. In this, either the upper or the lower terminals can be used as input terminals as long as the selection is consistent. For example, if one lower terminal is selected as the input terminal, all lower terminals should be input terminals.
- The wiring of the output terminals should be connected to the input terminals of the variable frequency drive.
- For choosing the appropriate wire size for your application, you should prefer NEC wiring practices.
- For power wiring, one must use only 75°C copper conductors unless the wire connector is marked for Alu/Cu. Otherwise, the use of aluminium wire is permitted.
- In standard 40°C ambient or less installations, you should leave space of three inches on all sides of the reactors and its enclosure so that there will be no interference with heat dissipation and there is enough wire bending space. This is a general instruction for typical applications.
- In case the reactor is being installed next to a heat-sensitive instrument or control device, it is advised to check for specific requirements or heat limitations.
- Since line reactors are designed to be wall-mounted or floor-mounted, a panel should be mounted by incorporating a bracket on large open-style devices. This will act as a shelf for supporting the reactor and/or enclosure.
- The line reactor should be installed in the lower half of the cabinet when dealing with an open-style device in an existing control cabinet, drive cabinet, motor control center, or other large enclosures. This will help prevent hot spots or pockets of heat and also allows better heat dissipation and heat convection.
Keeping all these guidelines in mind while installing a line reactor will help you avoid major losses and enhance efficiency.