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Reply to "Trolley with reversing bumpers"

As mentioned by others, Dallee, Azatrax and the like have a wide variety of clever gadgets to perform automated trolley actions.

The rub is how to allow time for the trolley to bump and reverse before starting the 10-sec stop delay.   For example, if a 153IR simply detects trolley presence near the turn-around bumper, it will instantly remove track power as the trolley approaches the bumper.  The trolley will immediately stop (in front of the 153IR) and the 153IR delay timer will never start because the trolley is right in front of it!  Or maybe I'm misunderstanding the earlier proposed configuration.

If you're comfortable with DIY wiring here's how I approached the application as initially proposed.  I even cobbled together a proof-of-concept using stuff I had lying around:

The key is a timer module which has two programmable time delays.  That is, when you trigger it, there is a first time delay.  After the first time delay expires, the relay then turns ON (which removes track power) for the 2nd time delay. When watching video, listen for the relay "click"...first when turning on for 10 sec (remove track power - bumper LED turns off), then when turning off after 10 sec (restore track power - bumper LED back on).

So for demo purposes, I set the first delay to 2.0 sec.  In other words, as the trolley approaches the bumper it triggers this 1st timer.  In the 2.0 sec (which you can see counting down on the digital display), the trolley is given time to hit the bumper, reverse, and leave the trigger zone.  Then the 10.0 sec starts which is when track power is removed (via relay).  I placed a magnet under the "trolley" to trigger a reed switch in the track bed.  The 2.0 sec and 10.0 sec delays can be adjusted.  There are many variants of these timer modules and are about $5 and widely available (eBay, Amazon, etc.).  They can be a nuisance to "program" with the mini buttons sort of like the old days trying to program a VCR!

ebay timer module

These modules require a source of DC power which can be from a DC-output wall-wart or from an AC-to-DC voltage converter module if you only have AC Accessory Voltage handy.

Note that rather than have insulated power blocks or sections, I simply remove ALL track power.  The advantage of this method is a single timer module can perform the timed stop function for BOTH ends.  You'd have a reed switch at each track end and either can start the timer module.

diy trolley station stop timer for 5 bucks

A reed switch is maybe 50 cents.  A magnet is maybe 10 cents.  Of course minimum order quantities and shipping etc. up-ends everything.  This is stuff I had lying around.  Yes, this method could be adapted to use insulated-rail triggering (one at each end) or even triggering via a pair of 153IR sensors (one at each end).  Again, I believe the "trick" is to manage (deal-with) the stated requirement of stopping AFTER the trolley reverses; any scheme that simply removes track power when the trolley is near the bumper will not behave as expected.

This approach does require a level of DIY-persistence that most guys just don't have the time for, and time is money!


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  • diy trolley station stop timer for 5 bucks
Last edited by stan2004
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