Leaders in:

Voltage Dip-Proofing

Earth Continuity Monitoring

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Welcome to Switching Systems website!

Our Voltage Dip Proofing Inverter (DPI) product line is ideal for for industrial applications that require protection against momentary interruptions and sags.It offers a simple cost effective solution that is easy to integrate into OEM products or retrofit to  existing equipment. The DPI provides complete protection for all sag depths and interruptions from 0 to 3 seconds. Note that in order achieve the support time needed to match your application it is necessary to select a DPI of the correct size based on supply voltage, load current & power factor for  the supported load. Sizing information is available at DPI & VDC Ranges>DPI Tools.

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  • Designed to be maintenance free for harsh industrial environments.
  • Easy 4 wire installation.
  • Wide range for loads of 2 to 25 amps.

Voltage Dip Proofing Inverter (DPI).

Switching Systems, was founded by F V Fischer and began operations in 1971 with the development and production of intrinsically safe earth continuity monitoring systems for the mining industry and over the last five decades, the company became the leading designer and manufacturer in this field. Switching Systems is a permit holder for the SABS mark for intrinsic safety and is a member of the South African Flameproof Association.

In the early 1980’s it was realized that there was a growing need for a device that would harden the control gear used in continuous industrial processes against the disruptive effects of momentary voltage dips and outages. It was during this period that the technology known as Voltage Dip Proofing was developed.

As an industry leader in industrial electronics, Switching Systems was approached in 1989 by ESKOM to develop a solution to problems they were encountering within their own power plants due to voltage dips. Currently the fifth largest utility in the world, they were experiencing drives and motors tripping due to voltage dips caused primarily by short circuits. They had suffered many trips on large fossil generating units and even tripping of complete power stations due to short circuits in the 22kV switchyard. The depression in supply voltage to the auxiliary system resulted in the contactors dropping out, stopping drives, which are critical to the continuous running of the generating units.

During the early 1970’s ESKOM installed auto re-close systems on auxiliary system drives but found them ineffective, and although they had UPS’s on their computer equipment, wanted specialized protection for the sensitive equipment in their motor control centers and switchboards. Subsequently, over a two-year period, a unique custom solution was developed by Switching Systems and successfully installed during 1990 and 1991 in all ESKOM large fossil power stations.

A range of DPI’s was developed and introduced to accommodate different applications. These ranged from 250VA to 4kVA, 110V AC to 240V AC and 50 or 60Hz. Designed to be used in different markets, the DPI is now exported worldwide, and is complimented by a range of Voltage Dip Compensators (VDC) for use in applications where equipment must comply with the F47 standard for semiconductor production equipment.

Switching Systems staff is a team dedicated to providing product quality and service excellence. Our innovative spirit and continuous product improvement ensures the reliability of our products.

We look forward to being of service to you.