turnout problems

[sherdog3]

I replaced the slide switches with 2 push button momentary switches, I wired them according to members instructions. the push button switches work, but the coil machine buzz's continuously. any ideas.

[Len]

Sounds like you may have 'Normally Closed' push buttons instead of 'Normally Open'. Or you may have a solder bridge between push button terminals.

You say you wired according to 'member directions', but don't include a link to those directions, so no way to verify if they were correct.

The wiring should be something like (N/O button: -/ +-)


     +-------/ +------------* Route A
Hot-|
     +-------/ +------------* Route B

Rtn-------------------------* Common

Note that only the 'Hot' connection, from one side of your AC power supply, runs through the push buttons. The 'Common' return (center wire of Bachmann green turnout wire) should connect directly to the other side of your AC power supply

Len

[Joe323]

You may need to install a Capacitive discharge unit.  Basically this is a small electronic circuit that you build or buy that places a large electronic capacitor (which stores up electricity) between your power source and the switch panel.  The stored electric charge is higher than the the 16 or so volts AC.  I believe around 21 to 25 VAC that gives the turnouts an extra puch to get them moving. 

[Joe323]

A Capacitor Discharge Unit should not be needed with the Bachmann turnout switch machine unless you are actuating more than one turnout at the same time or are using a power supply less than 16VAC.

Maybe thats your experience hunt but mine was that it helped alot.  Then again I never measured the voltage coming out of the power pack. Generally I only throw one turnout at a time.

[Joe323]

Hunt sorry I was typing quickly No disrespect intended.

Joe

[Jim Banner]

I don't know the voltage rating of the Bachmann turnouts either.  But when we apply 16 volts ac to the coils, the peak voltage is approximately 22.5 volts.  Many capacitor discharge machines charge their capacitors up to this peak voltage.  But it is dc, not ac.  When applied to the coils, the capacitor discharge machine applies basically the same peak voltage.  What makes it more effective is that it is applied for a longer time than a half cycle of ac.  DC can heat up a coil quicker than ac can.  This is because the dc has to overcome only the resistance of the coil while ac has to overcome its inductive reactance as well.  The capacitor discharge machine compensates for this by cutting off the current quite quickly as the capacitor discharges so that the total energy put into the coil is typically less than even a very fast push of the button with ac.

I have been playing around recently with what might be called a "capacitor charge" switch machine.  It applies only 12 volts dc to the coils (equal to the peak voltage of 8.5 volts ac.)  It is based on Ken Stapleton's "Electronic Turnout Switch."  Ken has developed a circuit that applies a lower voltage for a longer time than capacitor discharge machines - I would even call it a "gentle switch machine."  Unlike most capacitor discharge machines, there is no wait time to recharge the capacitor.  It is more like having a capacitor machine for each and every turnout.  So far, I have used them with Atlas turnout dual coil machines throwing hand laid stub switches and with unmodified Atlas and Bachmann turnouts.  Experiments are continuing but so far the results have been excellent.  You can see Ken's product at this link:
http://www3.sympatico.ca/kstapleton3/751D.HTM

Jim