On 1/2/2013 3:22 PM, RJ Kanary wrote:
It appears that you were victimized by the Field Reversing
scheme that was in vogue during the E-12 S and the early E-15.Obviously
an idea that was not well thought out, and poorly executed.Even a guy
that fixed cars and trucks for a living could see that was a good one to
repair, but not a good one to own.
I have to agree. My first Elec-trak was an E20 and it's been pretty much indestructible in terms of controller. The only problem was when one of the field diodes failed, cost a few bucks to replace all four diodes on card 4. And after 10 years of service I noticed the contactors for F were getting warm, so I simply flipped the contactors over and now I can run on the R ones for another 40 years or so.
The E15 is more of a fickle thing, the concept of reversing the field was cheaper to implement, but the result was a very annoying tendency to blow out the relay if the MOV is bad and you go from F to R quickly. New MOVs seem to make the problem go away but I'm guessing they blow up eventually.
Putting in E20 style reversing contactors would be the right way to go; I might just do it. But I like the standard speeds, quick performance, and simple reliability of the E20 system.
Chris