Yes, that is right, the second wire went to the wiper, the third wire went to the other end of the pot. To convert to a 2.5 K Pot, you can still connect the two ends together.
I also use the 2nd 5K pot as a idle control for the automatic transmission. Can either select the 1st 5K pot in standard mode or the 2nd 5K pot that adds about 300 rpm to the motor on start up. I found idling the motor at about 300 rpm during a quick stop and go, eliminates the start up surge from 0 rpm which may be as high as 600 motor ampere to less than 150 motor amperes which is about 50 battery ampere. Roland ----- Original Message ----- From: EVDL Administrator via EV<mailto:ev@lists.evdl.org> To: Electric Vehicle Discussion List<mailto:ev@lists.evdl.org> Sent: Friday, February 13, 2015 9:26 AM Subject: Re: [EVDL] PB-6 Extra Wire On 13 Feb 2015 at 8:12, Roland via EV wrote: > This third wire is the center tap of the 5K pot. It is use to limit the speed > of a low speed EV which limits the pot to 2.5K. Also you could parallel the > two end wires of the pot which will result in a 2.5K pot. > > > > Just cap off the center tap wire if you controller requires a 5K resistance. Roland, are you sure about that? I had a 3-wire potbox for my old PMC DCC- 96 controller, and unless my memory is failing me (which I admit is possible), the 3 wires were just the 3 normal terminals of a potentiometer - both outer ends and the wiper. It was not a tap. Bill, I would check the potbox with an ohmmeter. If I'm right, you should be able to find 2 wires that read 5k ohms across them at all times (regardless of potbox position). Those are the outer terminals of the potentiometer inside. Then, connect one lead of your ohmmeter to the remaining potbox wire (the wiper), and the other ohmmeter lead to each of the above two in turn. With one of the ends, you should see a resistance that varies from 0 to 5k ohms as you move the potbox lever. With your meter lead on the other wire, resistance should vary from 5k ohms to 0 ohms. To connect this potbox to most 2-wire-potbox controllers, use the pair of wires that varies from 0 to 5k ohms. (Warning, some controllers require a 5k to 0 range, so test with a light bulb before testing with your motor!) If Roland's description is right, your ohmmeter should be able to identify the two wires that vary from 0-5k as the lever position is increased. Those are the ones you want to use with most controllers. See the above warning. David Roden - Akron, Ohio, USA EVDL Administrator = = = = = = = = = = = = = = = = = = = = = = = = = = = = = EVDL Information: http://www.evdl.org/help/<http://www.evdl.org/help/> = = = = = = = = = = = = = = = = = = = = = = = = = = = = = Note: mail sent to "evpost" and "etpost" addresses will not reach me. To send a private message, please obtain my email address from the webpage http://www.evdl.org/help/<http://www.evdl.org/help/> . = = = = = = = = = = = = = = = = = = = = = = = = = = = = = _______________________________________________ UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub<http://www.evdl.org/help/index.html#usub> http://lists.evdl.org/listinfo.cgi/ev-evdl.org<http://lists.evdl.org/listinfo.cgi/ev-evdl.org> For EV drag racing discussion, please use NEDRA (http://groups.yahoo.com/group/NEDRA<http://groups.yahoo.com/group/NEDRA>) -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.evdl.org/private.cgi/ev-evdl.org/attachments/20150213/f30556fe/attachment.htm> _______________________________________________ UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub http://lists.evdl.org/listinfo.cgi/ev-evdl.org For EV drag racing discussion, please use NEDRA (http://groups.yahoo.com/group/NEDRA)
