On Friday 03 August 2007, RogerN wrote: >First see if you can find any markings indicating a manufacturer, if so > search for them on the web and look for a similar encoder, they might have > the wiring published online. If that doesn't work, I would ohm between > each color and black to make sure none are tied together, if the are, > that's probably your power wire. Red & black could be + and green & black > could be -. Many sensors used in industrial equipment use brown as + and > blue as -. Also ohm each wire to the encoder case, also check shield to > case. Your red & black pair could be power and the green could be a > ground. If the red and black are not tied together(ohms more than 30 or > so), try 5v on them. If you get the power right, channels A and B will > read an AC voltage when you turn the encoder, Index will only get a quick > spike once per rev. > >For fear of burning up something, If you can't find the manufacturer's name, > I would look at encoder wiring diagrams on some of the more popular encoder > brands. I know Automationdirect.com has encoders with online documentation > but I don't know if wiring color codes are common for other manufacturers. > >HTH >Roger Neal
I spent half an hour snooping around on that site w/o success. Everything I could find had quadrature encoders. I'm with RayH in that with that many wires, the possibility of its being a normal quadrature plus index encoder is pretty slim. Two other techniques come to mind. One is where an exciting current is supplied as a drive signal, and then 3 outputs which when decoded by that devices interface electronics, will translate to an absolute position with accuracy potential to small fractions of a minute of rotation. This could also be inverted by having a 3 phase driving signal, and a single phase output whose phase is compared to the 3 phases of the driving signal, again with potential accuracies in the fraction of a degree area. The index pulse if there is one, might serve as a rezeroing pulse for the electronics to calibrate it self with. But that would certainly require the electronics that normally are hooked to the other end of the cables. Is it possible to obtain that from the source where you obtained the lathe itself? The other possibility is that its a resolver, where one set of wires would be power, probably 5 volts, The next set, possibly the green one is an index at 0 output, and the other 3 would divide the full rotation in 1/2 turn, 1/4 turn, and 1/8 turn. But that on the face of it, would need about 4 or 5 more divisions to achieve sufficient accuracy. But one could make an educated guess as to that particular signal from a resolver by using the std nema color code sequence. The Bad Boys etc phrase comes to mind. :) If its all externally powered, then 5 sets of wires would let the resolution be divided further to 1/16th and 1/32nd of a turn, which with decent ballistics would allow thread cutting. As for an index, the MSB's 0-1 transition would suffice if that's the case. This is something that could possibly be determined by someone with a decent triggered oscilloscope, a _small_ power supply, and the knowledge to interpret what they see on the scopes screen while the spindle is turning at one of its slower speeds. Because the possibility of breaking the mirror and letting all the smoke out is pretty high, I'd explore the possibility of obtaining the rest of the electronics (and any surviving docs) that originally went with this lathe, it might at least put some stable dirt under your feet to stand on while investigating how it works. > ----- Original Message ----- > From: richard harris > To: Enhanced Machine Controller (EMC) > Sent: Friday, August 03, 2007 1:43 AM > Subject: [Emc-users] OT Encoder Question > > > Hello, > > First let me apologize for this off topic question, but I exhausted all > the responses google provided. I have a Hardinge lathe with an unknown > encoder mounted to the spindle. The encoder has 5 sets of wires. All are > twisted pair, one set is wrapped in red foil and is a red wire and a black > wire I assume this is the power. One set is wrapped in green foil, with a > green wire and a black wire. The last three sets are in blue foil, wire > colors are; brown/black, blue/black, yellow/black. I can speculate that > the blue foil are the channel where the colored wire is the channel and the > black is the inverse. That leaves the rather dubious green foil set of > wires. > > Any ideas, before I wire and hope? > <!--[if !supportLineBreakNewLine]--> > <!--[endif]--> > > > > >---------------------------------------------------------------------------- >-- Be a better Heartthrob. Get better relationship answers from someone who > knows. Yahoo! Answers - Check it out. > > >---------------------------------------------------------------------------- >-- > > > ------------------------------------------------------------------------- > This SF.net email is sponsored by: Splunk Inc. > Still grepping through log files to find problems? Stop. > Now Search log events and configuration files using AJAX and a browser. > Download your FREE copy of Splunk now >> http://get.splunk.com/ > > >---------------------------------------------------------------------------- >-- > > > _______________________________________________ > Emc-users mailing list > [email protected] > https://lists.sourceforge.net/lists/listinfo/emc-users -- Cheers, Gene "There are four boxes to be used in defense of liberty: soap, ballot, jury, and ammo. Please use in that order." -Ed Howdershelt (Author) Schshschshchsch. -- The Gorn, "Arena", stardate 3046.2 ------------------------------------------------------------------------- This SF.net email is sponsored by: Splunk Inc. Still grepping through log files to find problems? Stop. Now Search log events and configuration files using AJAX and a browser. Download your FREE copy of Splunk now >> http://get.splunk.com/ _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
