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SLarge Track Layouts - Important Public Message

Straight to the Public Announcement -

ARC PRO set for Digital Racing.

If you have a large track layout and you attempt to power up the ARC PRO using just one power supply, the ARC PRO will reset itself, similar to a power short.  Even if there are no cars on the track, the ARC PRO will continually reset just like a power short event.

Large Tracks MUST have BOTH power supplies plugged in before power is applied.  Use a power strip with a switch on it, plug both power supplies into the power strip and problem solved.


Now, How did I find this out, well, there's 6 hours of my life I'm not getting back....

I converted my Arc Pro for digital only, see forum thread here , I then installed power boosters from the Arc Pro base to strategic track pieces furthest away from the power base.  To test everything, I took ONE power supply, connected it up, and boom, continuous reset.  

Since I always triple check everything, couldn't understand what was going on.  Undid everything, grabbed my voltmeter, quadruple checked all my wiring, no idea what was causing it.  I then decided to only connect one end of the Arc Pro base to my track, leaving the other end unconnected, and it worked.  I then disconnected the connected end, connected the other end of the power base to the track on that side and powered up, that worked, tried to connect both ends of the Power Base to the track, reset.

Upon power up, I could hear the lane changer motors "clicking" right before the Arc Pro base would reset itself.  Hhhmmm, so I went around the track disconnecting each lane switch piece thinking there could be a short in one.  After removing enough pieces, I got a false positive, because, the Arc Pro started working, not because I removed a lane changer, just the fact I removed ENOUGH of them to where the single power supply wasn't getting overwhelmed.

After an hour of troubleshooting lane changers, then I had the idea that maybe, just maybe, the single power supply was getting overwhelmed because all the "Lane Changers" were energizing simultaneously.  So, I connected both power supplies to the ARC PRO and started to put my track back together, along with all the Power Booster track pieces, and whalaa, everything worked.

So, for anyone planning large track layouts with the ARC PRO, make sure both power supplies are connected to the Base and both go to a powerstrip so when all the lane change motors energize simultaneously, there's enough power supply to handle the surge.

Andy P.

1943 posts

Community Moderator

While I appreciate the message you are ultimately trying to communicate:

When running a large track (common rule of them is over 10 meters/30 feet) or when using more than 3 cars you should use two power supplies

and I also appreciate that it may have been frustrating figuring this out: To be honest you describing in full detail the behavior of ARC PRO when there is insufficient power power will surely help new users but I get the feeling you are trying to state there is a design flaw or something fundamentally wrong with ARC PRO that I would argue is not the case.

All powerbases produced that can drive more than 4 cars have 2 power inputs for a reason: You need extra power.

Also ANY layout, either analog or digital over 10 meters might have problems, particularly if the connections are nor perfect.

Finally, this very question has been asked on here (and other forums) many many times and answered, usually within a matter of hours.

I only have the ARC PRO upgrade powerbase and I admit the quick start guide does not mention when 2 power supplies are needed but the very first picture shows 2 being plugged in.

Slot racing's learning curve is unfortunately a bit steep, digital in particular. It is not helped that there are no standards for digital either. Still, once this curve is surmounted there are very few things that could be arduous to resolve.

Let me reiterate: Thanks to the pain you went through many will now know what happens when the track is underpowered. This is something that I have never done because I have always known that when either 4 or more cars are racing or if the track is over 10 meters you need 2 power supplies.

I would like to encourage people though to use the search function or ask questions before wording things in an accusatory to inflammatory manner.

If that was not your intent I apologize but as I am likely thousands of miles away from you I can't hear the inflection of your voice or see your body language to know your intentions are purely benevolent.

I am glad you got it sorted out, I have raced on a 20 meter track with 6 cars for 10 hours straight without problems (with 2 power supplies!) so I am sure things will work swimmingly now.

Enjoy the holiday weekend if you can!


665 posts

What is seriously missing from this discussion is how many lane changers were acceptable to use track with 1and 2' powerpacks.

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