abb group...the ward-leonard system proved to be a much improved speed control for mine hoists; abb...

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Page 1: ABB Group...the Ward-Leonard system proved to be a much improved speed control for mine hoists; ABB supplied such a system as early as 1904. However, the Ward-Leonard sys- tem had
Page 2: ABB Group...the Ward-Leonard system proved to be a much improved speed control for mine hoists; ABB supplied such a system as early as 1904. However, the Ward-Leonard sys- tem had
Page 3: ABB Group...the Ward-Leonard system proved to be a much improved speed control for mine hoists; ABB supplied such a system as early as 1904. However, the Ward-Leonard sys- tem had
Page 4: ABB Group...the Ward-Leonard system proved to be a much improved speed control for mine hoists; ABB supplied such a system as early as 1904. However, the Ward-Leonard sys- tem had