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Intermittent Power

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  • Intermittent Power


    After packing my Scalextric away for a number of years, I have brought it out and what I thought would be a easy afternoon with a simiple loop has turned into WTF is going wrong.

    When I put the cars on the track nothing happened, when I lifted the cars and pressed the throttle the car would run then stop, when I let go of the throttle and pressed it again same thing again. When I held the car up and it was running and set it back on the track it would stop.

    I disconnected the power base and just ran 12 volts to check the connections and that was all fine. Cleaned the track.

    Now the digial system is old, 6 car PB version 1.2 which I had converted to the simple-h mod with PB Pro Software and it all worked fine before I put it away, I also tried a the standard analog power base with the same results, used different cars, even motorbikes (analog).

    I have no idea where to start with this one, if anyone has any ideas that would great.


  • #2
    Let's see if I have this correct: Having the car lifted off the track - braids connected and the motor spinning - is working great, but when you place the rear of the car down on the track the motor stops spinning and the car doesn't go.
    If I have that correct then I think the car is shorting the track somehow.


    • #3
      Can I assume that pushing the car along while holding the throttle also does not get the car moving?
      Does the PB-Pro show any errors when you put the car down?
      Are you running the PB-Pro in analog (single lane, assuming you don't have the dual analog mod) or digital mode, or neither works?
      When you say that putting 12v straight to the rails works, does that mean the cars go just fine, but at full speed and crash?


      • #4
        Yes, when I lift the car and the braids are still in contact and the motor spins, when I place the rear wheels on the track it stops. However, even when I hold the rear wheels up and press the throttle the motor will spin then stop, when I let go of the throttle and press the throttle again and the motor will spin up again and stop. It just repeats it's self when I just press the throttle on and off.

        I tried it with a few cars some did this others didn't even spin, I could ID the cars to the controller but the motors wouldn't spin.

        The PB-Pro does not show any errors when I do this, so I don't think I'm shorting the track.

        I'm not running the PB-Pro in analog mode (haven't tried it). I just swapped out the digital power base with an analog power base.

        I removed the power base from the loop and just connected a different power supply to run the 12 volts through he track and used a multimeter to measure the voltage, I didn't think you run the cars off 12v direct.


        • #5
          You can't control them, but they'll run at full power if you put 12v to the rails. Measuring with a meter doesn't tell the whole story, though.

          In what way are you cleaning the track?


          • #6
            I use a rubber and Inox with a cloth to clean the track.

            When I connected a 12v power supply to the track, I'm just measuring the voltage to see if I have connectivity, I didn't run the cars on the track when I did this, plus I'm not sure if I can put a digital car just on 12 volts to test it with out taking the chip out.

            The analog cars I have tested with a variable power supply and they work fine.


            • #7
              Scalextric digital chipped cars will work on analog power. The only difference is they won't have brakes, even if your analog controllers do. If the digital cars work in analog mode (e.g. on an analog track like your analog cars work), then there's something wrong with the digital power base, most likely.

              Since you have PB-Pro+SH, you should have menu options to not only see how many amps are being drawn when things are happening (a car on the track with trigger pulled) but also to change the limit allowed by the base. It's possible that the limit has been reduced to a level that allows motors to spin when there is no load, but not when they are down on the track, which will require more power.


              • #8
                No worries, I'll also give the track and cars another going over to make sure there's nothing happening there.


                • #9
                  Very impressive Mr Flippant.
                  Could not remember that old pbpro-sh stuff any more.
                  Of course the advanced is a fog now , but pb4 is still unforgettable to me.


                  • #10
                    II ended up pulling all the cars apart and giving them a good over, changed braids and cleaned the track, now I'm back in business

                    Thanks for the help.


                    • #11
                      Pretty good indication that there was a messy braid causing a short somewhere.


                      • #12
                        Normal rule of thumb if the car runs when you lift rear wheels but not when set back on track. Braid or braid disc issue. When you lift the wheels it puts more pressure on the braid, this often helps make the connection. Lower the car down and the pressure is removed and away goes conductivity. With many Slot Cars, Scalextric included, the front tires also bear too much weight causing poor pressure on the braid to rail contact. Quick test, does the car run ok if I remove the front tires. If the answer is yes you have poor braid contact with the track rails. I am constantly amazed that Scalextric make cars where front tire size means you have less that half the guide in the slot. Even on analog this is a serious issue, fix that by fitting smaller front tires and the car runs better, turns better and has better pick up and brakes.

                        Hope this also helps some, also check track connections for loose rails often happens.

                        Last edited by Scaleracing; 06-13-2020, 05:42 PM.
                        Alan Smith
                        SCI Owner.



                        • #13
                          Thanks, it was simpler when you 8yrs old, then it's "Dad it's not working fix it" now there is so much more to it.