Just make sure ev@lists.evdl.org is in your "To:". I'll reply to the group with this message.
5G isn't "more power", it's just using some of the same frequencies that older radar altimeters use. So the FCC has restricted those frequencies near airports. 100 feet from the tower could definitely be considered "near field". I'd start by making sure all your control signals, especially the throttle wiring is twisted and/or shielded as Bill mentioned. Make sure the shields are only connected at one end of the wiring, probably best to be the controller side. Add some snap-on RF chokes at each end of the cable too, such as these: https://amzn.to/3XnYZnG You could also add some filtering, such as a 0.1uF ceramic capacitor from the accelerator signal to ground at the controller, and from the +v signal to ground. ("outer" terminal of the pot). Again, where are you located? Maybe me or one of the other experienced guys on the list are local and could come help? On Sat, Jun 24, 2023 at 9:56 AM David Heacock <d.heac...@yahoo.com> wrote: > Phil, sorry, I have not been on the the discussion list for many years and > I thought by replying maybe it was going back to the entire group. I do > want to share this with everyone if they feel it is of some value. The one > cell tower that I use to test modifications is about one mile from my house > and it does not affect the car until i am basically on the street right > next to it, say 100 feet from the tower base. I forgot to also mention I > have a friend who is a pilot for the airlines and about a year ago or so > they had a notice come out that the new G5 cell signal levels had increased > and could interfere with their radar altimeters and modifications were > going to be made. > > How do I send all this to the group? > > On Saturday, June 24, 2023 at 09:21:02 AM PDT, (-Phil-) < > p...@ingineerix.com> wrote: > > > I just don't see how a cell tower a mile away could affect you. If it > were right next door, maybe. Where are you located? > > I notice you didn't post your reply to the whole list, but I think you > should. I will respect your decision and not post my reply, but keeping > this private means the next guy won't benefit from the group's wisdom. > > On Fri, Jun 23, 2023 at 4:58 PM David Heacock <d.heac...@yahoo.com> wrote: > > Phil, I first want to thank you very much for your reply which has some > very useful information. I have been trying to figure out the problem for > some time and most everyone finds it hard to believe that the cell tower > can be the issue. Over time I have narrowed down the problem to the cell > towers by trial and error. I have a cell tower, which is made to look like > a large tree, about one mile from my house. I have had the car quit a > couple of times in that area when I discovered the tower. The tower is > located about 100 or so feet from the side of the road behind a shopping > center in an adjacent parking lot near a hotel. What I have found is that > when I drive the car slowly on the street I get to a point where the > interference happens and the car will cut out. Sometimes I can move the > car in reverse less than 10 feet and the interference goes away and the car > drives normally until I move it back to the point where the interference > happened. The road is flat in this area and I have actually needed to push > the car 10-20 to get it out of the interference zone. I have also had this > happen on the local freeway where you can feel the car cut out and then > come back on again and I know where there is another cell tower in the > area. At one point I discovered by driving in the far right hand lane I > would not experience the interference as there is a hill between the tower > and the car. However, by driving in the third lane the tower had a more > direct line of sight to the car because It was not behind the hill off the > road and I would experience the interference, if that make sense? > > Having said all that someone else mentioned the same possible problem with > my cell phone in the car but you explained why this might happen. I think > at one point I tried to wrap the cell phone in some RF screen material but > it didn't solve the issue. I guess from what you are saying I am going to > have to leave my phone at home and try it again to see what happens. I > should say that my Avanti has a fiberglass body and from what I understand > the fiberglass does not stop RF radiation? > > Thanks for you comment about a perfect storm because I would not rule that > out. I have tried to learn about how things should be wired but from what > you saying I probably have some issues to correct. The main controller is > a GEVCU from EVTV and upon contacting them I found out that they have never > heard of this being a problem. I recently wrapped the controller and built > a box around it but it didn't make any difference. A number of my other > components such as my BMS and chargers are made by Thunderstruck motors and > upon contacting them they also didn't feel that their components would > cause such an issue. The motor and inverter is made by UQM and I purchased > them as a unit from Thunderstruck and I believe they came out of a Coda > car. The HV wiring between them are shielded which I found out the hard > way and they are the factory cables. > > For the battery pack I have eight 5 kWH modules that came out of the Smith > trucks so they are basically factory made. However, here is where the bad > engineering may be involved. I have six of these modules in the rear of > the car and two in the front for weight distribution. The HV cables > between the front and the rear are basically 2-0 welding wire which are not > shielded. Also to keep the cable length as short as possible, the two > cables running from the rear pack to the front pack run under the car along > the frame rails, one on either side of the car. The HV cables from the > battery pack to my contactors are also made of the same cable and not > shielded. When you say limit the length of cable between the controller > and the motor are you talking about between the inverter and the motor? As > mentioned these cables are factory original and are shielded and as short > as they can be. > > I'm not all that smart about all these electronics so I'm not sure what > you mean by battery loop inductance. Motor and the inverter are connected > with a ground cable that came with them and the inverter is basically > bolted to the frame of the car so I think things are grounded but maybe I > need additional grounding. I do not have a heavy flat braided jumper > between the motor and inverter so I guess I could improve on the original > ground wire connection. > > I have tried all kinds of shielding with no results and like you say maybe > it is internal interference or my cell phone. > > Thanks again, I welcome any and all comments. David > > On Friday, June 23, 2023 at 10:49:11 AM PDT, (-Phil-) <p...@ingineerix.com> > wrote: > > > Unless you have a cell tower right in your driveway (near-field), it's > highly unlikely that's the cause. More likely would be a local cell-phone > (yours) inside the car causing this when it responds to control channel > messages or you are on a call. > > The most energy a cell tower puts out is somewhere below a few watts in > total, and due to the Inverse Square law: The radiation Intensity is > inversely proportional to the square of the distance. A WiFi access point > close to your car is going to expose it to more RF than a cell tower a > block away, but in either case the energy at the car is super low. It > would take an exceptionally "perfect storm" of bad engineering in the EV to > have this be a cause. > > More likely it's interfering with itself. The amount of electrical and RF > noise in an EV is astounding, which is why even on carefully engineered > production EVs, AM radio doesn't work so well, and why it's being removed > from most of them. There are myriad ways your home-built EV could be doing > this, but impossible to determine without a thorough analysis. Though > obvious things to consider; Did you use shielded HV cables? Did you take > steps to minimize wire length, especially from controller to motor? Are > these routed as close together as practical? Are they shielded? What > about the battery wiring? Did you design the layout to minimize battery > loop inductance? Is the motor and controller grounded to the body with a > heavy flat braided jumper? > > On Fri, Jun 23, 2023 at 10:30 AM David Heacock via EV <ev@lists.evdl.org> > wrote: > > I have converted a 1985 Avanti to an EV and with the current LFP battery > pack I have a reasonable range of about 100 miles. Everything works well > with different components from different sources. However, one problem I > have yet to resolve is what appears to be interference from Cell towers > which basically seems to cut out the throttle and at slow speeds can > actually cause the vehicle to shut off and then come back on as the car > moves relative to the cell tower position. I have contacted a number of > people and suppliers about the issue and tried a number of things to > provide RF protection but have not been able to solve the problem. Has > anyone ever experienced this issue and a possible solution? > David Heacock > -------------- next part -------------- > An HTML attachment was scrubbed... > URL: < > http://lists.evdl.org/private.cgi/ev-evdl.org/attachments/20230623/c58f993d/attachment.htm > > > _______________________________________________ > Address messages to ev@lists.evdl.org > No other addresses in TO and CC fields > HELP: http://www.evdl.org/help/ > > -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.evdl.org/private.cgi/ev-evdl.org/attachments/20230624/14e882a3/attachment.htm> _______________________________________________ Address messages to ev@lists.evdl.org No other addresses in TO and CC fields HELP: http://www.evdl.org/help/
