kblc 240d schematic?

Has anyone got a schematic/circuit diagram for a kblc 240d, a motor controller used in many small lathes and mills?
I have one, but it's unreadable :(.
Apparently there is/was another one about, but I can't find it.
Thanks,
-- Peter Fairbrother
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Hi Peter,
If you should find one, I'd be very pleased to have a copy!
The usual failure is the SCRs going short-circuit, if I remember correctly they're rated 10A, 600V peak-inverse, and Very Importantly, insulated tab construction. The other common failure is the diodes failing, they're on the back row with the SCRs, similar rating and isolation.
Are you planning to repair 'em, modify 'em or after more of a clue as to how they do what they do?
I heard that they shut the stable door after the horse had bolted by making the schematics private *after* the Chinese had "emulated their success"...
Dave H.

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news.virginmedia.com wrote:

I want to repair the one on my lathe. It goes very slowly if the accel pot is turned to the region it's not supposed to be put in, and not at all otherwise.

That's more than a bit silly - it's at most a day's work for even a novice electronic engineer to covert a physical circuit like that to a diagram, and I'm sure some Chinaman would do it ver' cheap.
Plus it gives the impression that they are hard to repair, and less desirable for that. And wasteful, and ungreen ...
-- Peter Fairbrother

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Peter, you have mail (assuming the email address is good!), hope it helps?
Dave H.
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news.virginmedia.com wrote:

Yes, very much so.
Now working. C17 failed open-circuit.
Thanks again, and many thanks to the others who sent stuff too. Now to make some swarf! :)
-- Peter Fairbrother
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Hi Peter,
If you should find one, I'd be very pleased to have a copy!
The usual failure is the SCRs going short-circuit, if I remember correctly they're rated 10A, 600V peak-inverse, and Very Importantly, insulated tab construction. The other common failure is the diodes failing, they're on the back row with the SCRs, similar rating and isolation.
Are you planning to repair 'em, modify 'em or after more of a clue as to how they do what they do?
I heard that they shut the stable door after the horse had bolted by making the schematics private *after* the Chinese had "emulated their success"...
Dave H.

Add pictures here
<% if( /^image/.test(type) ){ %>
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