1983, GridStone factory for AVR with servo motor was started and the first AVR with servo motor was successfully built in China.
1985. factory for transformer was started
1998. New office and factory of AVR were started in Shanghai, China.
2002. The first AVR controlled by SCR was released, and massive production started at end of the year.
2005. GridStone was invited and joined the China Power Supply Association.
2008. Brand name "Shanghai Voltage Regulator" was started in China.
2009. New type AVR with SCR was released. More fast, more reliable and more intelligent.
2010. The first frequency and voltage regulator with IGBT control is released.
2013. 12pcs AVR with SCR were installed in Australia, and have been working well since then.
2014. New factory for transformer was started.

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