4: RichardNabuda@Email.MSN.com
Overall I found this to be an excellent book. I enjoyed every page, and in particular tracing out circuit operations of the various schematics. I thought the diversity of circuits was great.Nowhere in the title did I see "Basics of" or Fundementals of". This is not a book for the novice. The reader must have a good understanding of AC and DC motors, and solid state theory, circiuts, and devices. I found the concatenation of induction motors, and the Kramer speed control system very interesting. I have many old industrial control books, but none shows these systems. There are several errors, and examples of such are: Page 44, Para 3 is completely wrong. The proper way to reverse direction of compound motors is to reverse A1 and A2. Page 57, para 2 relates to this proper method. Fig. 5-9 Q102 shows a JFET- should be a UJT. Fig. 5-13 Q1 same thing. Fig. 5-10 has negative 250 VDC lines to emitters of Q532-Q536 and Q552-Q556 missing. Eliminate lead from motor to bottom of C541. Fig. 6-11 motor will never reverse with this scheme. Turning dial in opposite direction FWD biasis Q2 turning on Q1 which energizes RY2. RY1 drops out turning system off. Motor never runs CCW. I have a comprehensive technical library, and one of my books is by this author entitled "Design and Operation of Regulated Power Supplies". It's an old book, and it's full of solid state circuits. I am indebted to authors like Mr Gottlieb, for it's their writings that enabled me to learn solid state electronics.
|
