You're welcome.
I'm glad I could help.
Tygerdawg said:
With examples, problems, & lab exercises this could be a textbook!
That takes me back to one of the more enjoyable challenges that I have encountered.
In the early 80s I was hired to develop an industrial controls course for industrial electricians.
The course must be a hands on course.
The course equipment must be portable and easily shipped by freight. The area of jurisdiction where the course was to be presented was about the same area as Texas.
We used 1/4 HP three phase motors and combination motor starters from a variety of manufacturers.
We used industrial control relays and industrial push buttons and selector switches.
The text book/work book would present a control problem and supply a basic diagram.
The students would wire the equipment according to the diagram and prove the proper operation.
The students would then be presented with additional operating conditions. For example, a simple two conveyor interlock may have a shutdown timer added to empty the belts during a normal stop.
The students would then be asked to develop the wiring diagram themselves and wire it up.
Instructor challenges: When the students encountered a problem, the instructor would check the students diagram for mistakes, and if the diagram looked good then check the wiring.
The challenge then was to ask questions thet would lead the students to discovering the mistake on their own.
Grading/ passing. There was no failure, other than dropping out of the course.
The students paired off and most often students of comparable ability would team up.
The students worked through the workbook at their own pace. At the end of the course, some slower students had completed the basic single motor circuits. The faster students would be well into complicated interlocking schemes with multiple motors and relays.
But, all students knew what they knew. Some students had learned more than others, but all knew well what they had learned.
Initially I planned on using shaded pole motors and cheap plug in relays. The estimate for materials was $800. A decision was made to use actual three phase motors and industrial combination starters. The price went up.
Later I was it was decided to build two classroom sets rather than one set.
The final cost of material was $20,000, a 2500% overrun. Even nuclear power plants don't see overruns like that.
And I was thanked and complimented on a job well done.
Bill
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Ohm's law
Not just a good idea;
It's the LAW!
