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Quindar Quadraphase PLC Manual

Quindar Quadraphase PLC Manual

Quindar Quadraphase PLC Manual

(OP)
Hey folks,
   I am working on a project at a substation that has some really old equipment in it. It appears that they are using a Quindar Quadraphase freqency shift keying PLC on one of their lines. I have done extensive web searching and have not been able to obtain a manual for this device. It appears that Quindar (aside-suppose this is where NASA got its "Quindar Tones"?) pioneered this type of equipment and became QEI, Incorporated, but it doesn't seem that that company is around any longer. Does anyone happen to have one of these guys?
    Thanks in advance!
          Carl

RE: Quindar Quadraphase PLC Manual

What you might have to do is to reverse engineer this device. Sounds to me like it has a quad phase shift keyed modem in it and could be a say 100 KHz version of a Bell 212 modem.

I have a similar problem with getting inrush current data for electronic fluorescent ballasts from the manufacturers - the easiest way is to remove the metal case, soak the ballast in diesel fuel, then take apart the printed circuit board and analyze what kind of circuitry is used to limit inrush current. Usually, there is no circuit to limit inrush current particularly on 220 to 277 volts but by knowing what kind of power supply capacitors there are I can get an estimate. For one make (GE) and model series the inrush current on 277 volts ranges from 600% to 3,600% of nameplate current depending on the number of lamps and ballast factor.

Mike Cole, mc5w@earthlink.net

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