15 Jan Protection of variable frequency drivers and static-starters
SPU devices designed by MD Equipos Tecnológicos guarantee the protection of Variable Frequency Drives- VFDs, and Static-Starters against the undesirable surge effects.
Both VFDs and soft Soft-Starters are electronic devices based on microcontroller technology. For this reason, surge effects affect these devices directly by causing considerable damages.
These devices guarantee the protection of VFDs thanks to:
- Its low residual voltage, which is adjustable to the supply voltage.
- The common protection mode- Line-to-Line and Line-to-Neutral, and differential protection mode- Line-to-Earth, Neutral-to-Earth, respectively.
- Its high discharge capacity.
- Frequency filtering of transient peaks.
VFDs and the different elements with non-lineal respones such as rectifiers, switched sources or welding machines that section the wave, all of them produce peaks and voltage harmonics multiple of its operating frequency. These elements such as tristors, rectifiers, switching power supplies or solder machines show a linear response.
These harmonics are transmitted over the network and may affect communication processes; PLCs, data buses, probes, etc.
These communication processes are carried out by very low-power high frequency signals. Therefore, if similar frequencies are induced on the communication cables- mainly generated by variable speed drives, these frequencies will mask the communication frequency and will affect the system.
Regarding the aforementioned issues, MD claim it is necessary to protect VLFS and Static-starters by settling overvoltage and harmonic filters, especially in electrical switchboards that supply eletronic components.
VFDs and every element responsible of the wave sectioning produce voltage peaks and voltage harmonics, which are multiple of its operating frequency.
Regarding the aforementioned issues, MD claim it is necessary to protect VLFS and Static-starters by settling overvoltage and harmonic filters, specially in electrical switchboards that supply eletronic components. The more critical this is for the operation of the installation, the more essential it will be to settle a SPU filter.
In addition, the design of SPU devices allows the implementation of accessory modules, as well as its adaptation to the needs of each installation to guarantee safety and a propper operation.