Incorporated in 1975, S & S Power Switchgear Limited is a Holding Company for the Group, which comprises of Acrastyle Power (India) Limited, Acrastyle Ltd U.K, S&S Power Switchgear Equipment Ltd, Acrastyle EPS Technologies Ltd and Acrastyle Switchgear Ltd U.K. The Company is a part of Power and T&D Equipment industry; focused on Switchgear, Protection & Control Systems, associated products and services.

It manufactures electrical protection equipment required for transmission and distribution of electricity. In 1990, Sushil Jalan and Associates of the Jalan group took over the management by acquiring a controlling interest.

At present, the company manufactures a wide range of high-tension and low- tension electrical protection equipments such as circuit-breakers, miniature circuit breakers, isolators upto 420 kV and fusegears. The company was the first to bring in vacuum breaker technology by collaborating technically with Brush Switchgear of the Hawker Siddeley group, UK. In 1985, in collaboration with South Wales Switchgear, it launched a new series of SF6 indoor and outdoor circuit-breakers. In 1988, it entered into a collaboration with AEG Germany, to manufacture miniature circuit-breakers.

The company's major clients include state electricity boards, NTPC, NHPC, Power Grid Corporation, NEEPCO, BHEL, NPTC and NLC. The clientele also includes Hawker Siddeley, Australia; Top Rank Corporation, Malaysia; AEG, Argentina; etc.

In 1992, it acquired Railway Products (India) (RPIL) from Sundaram Clayton of the TVS group and turned it into a wholly-owned subsidiary. RPIL manufactures braking and signalling equipment for the Railways.

A joint venture has been signed with Siemens for a switchgear project to manufacture vacuum interrupters. The other joint venture signed is with Union Switch & Signal, US, to run the existing operation of the subsidiary, Railway Products (India). It has also entered into a joint venture with Top Rank Corp., Malaysia, to form a company in Malaysia under the name S & S Power Corporation (SSPC). SSPC manufactures circuit breakers.

It also developed a indoor breaker at 31.5 KA used by generating stations and indoor and outdoor breakers 36 KV compliant to international standards during 1998-99.

During the year 1999-2000, the company has obtained ISO 9001 Certification from RWTUV and has successfully undergone two surveillance audits on ISO 9001 by the said certifying authority. Due to the erosion of the net worth the company has become sick in terms of SICA and has decided to make a reference to the BIFR for formulating a scheme of rehabilitation.

A new design of RD145 Disconnector was introduced to suit for ICE LOADING applications,Induced Current Switching and Bus Transfer Applications.To supply in the UK markets these products has been developed and it has been approved by National Grid Corporation UK.

In 2007, the Company set up an Indian Business for integrating protection systems with the expertise of Acrastyle UK had. The new plant at M M Nagar, near Chennai now houses two units- Acrastyle India Power Limited for Control and Relay Panel and S&S Power Switchgear Limited for Medium Voltage Switchgear Manufacturing. In 2010, it formed a Joint Venture with Coelme Italy for EHV Disconnectors and created S&S Power Switchgear Equipment (SSPSE) Legal Entity. It got very large installed base of Disconnectors in India with over 45000 installations to its credit and more than 10000 outside India. Technology agreement with EPS Switchgear UK for upgrading products with Maglatch solutions was entered in 2009 and a new generation of special switchgears for special applications started to take takes shape in MV Switchgear Offerings.