Need More Power!

Discussion in 'FAQs' started by Play-Doh, Apr 21, 2008.

  1. Play-Doh

    Play-Doh Member

    Hey Folks

    So I finally fired up my control board for my yard. This board powers my switches as well as snap relays which trip an LED light to indicate position. The wiring works great!

    Now, the problem

    I am running a respectable tech 4 260 with 18.5 VA. This is more that enough to power my switch machines, but it comes up short when it comes to tripping the switch on the relay as well....not to mention I have a chain of 10 of them! So, im needing more AC power, but I dont need a boheamuth (sp?) of a transformer.

    Does someone make a seperate AC output device for these types of situations?
  2. 60103

    60103 Pooh Bah

    Are you running trains from the tech 4 at the same time?
    You probably need a CDU, Capacitor Discharge Unit. This is like the unit that pops the flash on your camera; a low current charges a capacitor but when you release it there's quite a high current that really throws your switches.
    It also gives you a DC output so you can do things with diodes.

    There are some on the market, but you can build your own from some simple parts. There are threads on the gauge with diagrams.
  3. ezdays

    ezdays Out AZ way

    Do you know what the voltage/current rating is on the relays you're using? The Tech4/260 is rate for total power out, meaning if you're running trains, you have less power for accessories, especially auxiliary relays. You should be able to get buy with a separt transformer for your accessories.
  4. Play-Doh

    Play-Doh Member

    Actually im having this issue and train hasnt even been on the rails. I know the atlas snap relay says it requires a minimum 16-18 volts momentary power. Now, while my tech 4 does throw 18 at its max, its not enough when I have the atlas switch machine to power at the same time. When both things require a momentary 18 volts to throw the switch, its coming up short. Like I said, im not running any trains when I do this.

    Any thoughts? Thanks!
  5. MasonJar

    MasonJar It's not rocket surgery

    How many are you trying to throw at the same time?

  6. Play-Doh

    Play-Doh Member

    Im just throwing one set (switch machine and relay) at the same time. The snap relays are designed to be used this way with the switch machines. However the paperwork does warn that extra power is needed. I notice the first set in the chain works correctly most of the time because it is closest to the power source, but still not 100% of the time. This is yet another indicator of not enough power. I spoke with my LHS guru who has been following my project and said my diagnonis sound correct, but had no idea on how to remedy the situation.

    I scanned walthers yesterday but didnt see anything independent in the AC department.
  7. ezdays

    ezdays Out AZ way

    It's not the voltage, but the power (voltage X current). When you have a higher current load and it exceeds the max power output, then the voltage will drop to compensate. The initial inrush current for a switch machine or a relay is always going to be higher than what it takes to sustain it. As Andrew is trying to say, the more switches or relays you try to operate at the same time, the higher the load regardless of whether you have trains running at the time or not.
  8. ezdays

    ezdays Out AZ way

    You can go to Radio Shack and buy a separate transformer, either 12 or 18 volts with up to five amps output. If the machines closest to the supply work, then you have to look to the size of the wire and the connections going to the other ones. Again, you are trying to throw a switch machine and a relay at the same time, and I have no idea what the current draw is for the relay coil.
  9. lester perry

    lester perry Active Member

    I use a capacitor that I purchased several years ago. It is made by circuitron. I don't know if it still available. i think it is supposed to throw up to 16 snap switches at one time. It works great
  10. porkypine52

    porkypine52 New Member

    You have several ways to power your turnouts.
    1) Go Radio Shack and buy a small plug in the wall transformer(wall wart).

    2) Go dig through the junk box and find an old cheap power pack. The kind that came with a trainset would work just fine. If you don't have one ask one of your fellow modelers in the area. It doesn't matter if the speed control side of the transformer works at all, all you are after is the AC out put.

    3) There are several places where you can get plans on how to build your own power supply.

    As several posters have stated to use a Capacitor Discharge Unit to throw your turnouts. You can buy CD units already built. The current issue of N-SCALE MAGAZINE has an excellent article on building your own.
  11. bitlerisvj

    bitlerisvj New Member

    I was gonna say to go to Radio Shack and pick up one of these: - Power & Batteries: Home & office power: AC (Home) adapters: 18/24VAC 1000mA AC-to-AC Adapter
    It is an 18 volt 1 amp wall wart.
    Radio Shack used to seel 18 volt 3 amp transformers, but I don't see them anymore. Maybe an old Radio Shack near your home could have one on the shelf still.?
    However, after re-reading your post, I am not sure what you should get. Each LED sucks about 2 volts off the top, and if you also have a relay that will take some more. What need to do is to use a Volt meter and see what kind of voltage is getting to the switch machine when you push the button. I am using Tortoise machines which have voltage on them at all times. Currently I have about 12.5 volts driving them and one LED drops the voltage a little, but I don't notice any difference in closure. However, I have one Tortoise where I have 2 LEDs driven, and I can see very clearly that the Tortoise is slower and doesn't have the drive the others do. It is getting only about 9.1 volts to it. I have to make sure that particular switch (turnout) is free from any binds whatsoever.
    So, you may actually need 24 volts, but only measuring the voltage drop will tell what you really need.
    Good luck and regards, Vic Bitleris

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