toggle switches

Far right in this photo, HY 2W01G  Bridge Rectifier.  Click on the underlined phrase to link an HY spec. sheet.   This is an Electric RR drive board installed in a Rich Yoder GE 44 tonner.  There are (4) terminals. +, - and (2) ~(AC) 

Bridge Rectifiers and diagrams

So, how many toggles would this one circuit operate in parallel?

I appreciate Dale sharing his diagram with us.  That is an interesting way to throw the switch and it leaves the toggle switch in one position or the other as an indicator of how the switch is thrown.  I do not know if Atlas switches ever use a non derailing feature, but it looks like it would be difficult to hook up using this capaciter throw method. As for how many toggle switches can use the same rectifier, I think the limiting factor would be charging multiple capacitors when first turning on your pike.  I think the 33 ohm resistor goes with each switch. If there were to be multiple switches of the same recitifier, a resistor in series with the recitifier that would prevent overloading it might do the job.  Dale's drawing shows a 6 amp bridge, so a 3 or 4 ohm resister should work. Someone with more electrical knowledge than I have should check me on this.

Wouldn't it be a whole lot easier to use Tortoise Switch Machines. They're hidden and much easier to wire up as you don't need any of those extra components. I don't know squat about electronics, but that seems like a lot of work to wire switches in a control panel. 

Hi David

You only need one resistor but you could use multiple ones and you need only bridge. The 33 ohm slows the charging of the capacitor to prevent arcing of the switch contacts when it charges. It charges very fast but is not a dead short in the beginning of the charge,you could use a number of values.  There is the resistance of the machine coil when it discharges (rate 1.1RC). So with a 1000uf capacitor and maybe 500 ohm resistance of the coil (never measured it),  the capacitor discharges in maybe about 1/2 second. (1000/1000000 times 500 times 1.1).  None of these values are written in stone,you can play around with them. Even if half of all the capacitors charged at once when the layout is powered,the 33 ohm should work.

Only one bridge is needed. If you have a lot of switches just use a 25 amp one. Cost about $3.

You could hook relay contacts in series to the machine power and use capacitor discharge into the relay coil. Or you can just use relay contacts for capacitor discharge the same as the switch. In this manner you can automate this feature and get non derailing or automatic switch throwing if you were automating a passing siding for example.

A different use of capacitor discharge is shown here discharged into the relay coil for timing circuits

http://www.jcstudiosinc.com/OG...AndWhistleController

Automating a passing siding is shown here but not with Atlas switches but I think it could be done the way described above

http://www.jcstudiosinc.com/Bl...=856&categoryId=

I am not an engineer and studied to the wrong material in science class, (the teacher was a very shapely redhead) so any suggestions of improvement is welcome. Someone asked for plug and play but I just goof off and guess in my basement. However 2200 uf 35 volt usually throws any machine. Capacitor discharge is a lot better IMO than the switch Atlas provides. Lots of these get fried.

Dale H

Yes if you have them or buy them. However this is what came with my Atlas switches. 

Dale H

What do the 'squiggles' mean on the bridge? Polarizing isn't necessary?

The "squiggles" are the AC input pins of the bridge.  The basic purpose of a bridge rectifier is to take AC in and produce DC.  The difference between a bridge and a single diode is with a bridge you get full wave rectified DC instead of half-wave rectified DC.

Well, the brick will charge the caps a bit faster, but it should work.

Ok, next question: If the BR converts AC to DC, can we eliminate the BR if we started out with a DC power supply just for the switches.

Yes assuming it has sufficient power.

Dale H

So, what would the circuit look like in that case? Just trying to simplify installation of 25 ON/ON toggles to show point position.

You're the man, Dale! Thanks.