I think I know the answer, but I'll ask here too.
I have three tortoises on the layout (others are snap switches). All three are (were) powered by a 6V 200mA power supply that overheated and shutdown. This is the second little supply to go.
Am I right/safe in thinking I need a beefier supply and beefier wire? Two of the tortoises are at long runs (20 feet) of phone wire.
If I put in a 9V and some 18 gauge speaker wire that would be better?
The tortoise will handle up to 12 volts and DC. They won't work on AC. 6V is way too little in my opinion. Just using heavier wire with 6volts I don't think will help you! I used the telephone wire too but with the 12 volts @ 20' or more with no problems. Jim
A 6 volt wall wart is underpowered for Tortoise usage.
The instruction sheet for the Tortoise states as follows:
The motor in the TORTOISE is powered continuously and merely stalls out at the end of the throw. The motor will not be harmed by continuous application of 12 volts DC or less. In fact, even if AC is inadvertently applied to the motor terminals, no harm will be done as long as it is 12 volts or less. The TORTOISE will not work with AC , of course, but it will not be damaged. This system uses the most basic power source, a simple DC supply of not more than 12 volts. Lesser voltages will make the TORTOISE run slower (and quieter). The power supply need not be filtered. Each TORTOISE will draw 15-16 ma. at stall, so 30 switch machines can be powered by a single 9 or 12 volt, 500 ma. wall plug adapter .
Rich
Alton Junction
Are you using this supply for anything else besides the Tortoises? It would be at least instructive to measure the voltage at the terminals when you're running. Also, measure the current. While I would also recommend 9 volts for running Tortoises, I don't think that just 3 of them should have taken out the supply.
It takes an iron man to play with a toy iron horse.
3 Tortoises certainly aren't overloading a 200ma power supply. They draw 15-18ma each when stalled, so you should be able to power 8-10 of them with that. 6V is a bit low though, 9V seems to be a "sweet spot" where they move fast enough but are much quieter than when run on 12V.
--Randy
Modeling the Reading Railroad in the 1950's
Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.
Cisco Kid I have three tortoises on the layout (others are snap switches).
I have three tortoises on the layout (others are snap switches).
If the snap switches are on the same power supply, they're the ones burning it out. Snap switches draw a considerably high amperage when thrown.
Thanks, gentlemen.
Yes, I am puzzled by just three burning out the power supply. Mind you, I keep buying the power supplies at the junk store (no electronics store here in my one-horse town). Think I will use a brand new 9 V one next.
Ah, but I did read the instructions. They make more of a point of not using more than 12V and suggest 9 to 12 for up to 30 Tortoises....leaving the impression 6V not out of the question. But the proof is in the failures....I think this one failed when I was rapidly throwing them to correct an oversight when the Santa Fe freight was bearing down on them at a good clip.
No, my several dozen snap switches are on two different 12 V supplies with a "Snapper" between....
Thanks for the info about the wiring etc. Should be no problem now.
I looked but I couldn't immediately find a reference to how much the Tortoise draws while moving, as opposed to how much it draws while stalled. If it draws significantly more than the 15-16 ma stall current while in motion, and you activated all 3 at once, that might explain the problem.
Does anyone know how much they draw while moving?
They draw less current when moving than when stalled.
Significantly less when moving - that's why series LEDs dim or nearly go out while the Tortoise is moving, then brighten up when they motor stalls. The "moving" current is almost too low to even light an LED.
Instead of the cheap transformers you're using, a better choice would probably be a computer power supply -- even a used one. Their output is 12 Volts and 5 Volts DC at a higher Amperage rating than those cheap ones.
However, install a fuse. 12V at 20-40 amps is serious welding power and you don;t want that runnign aroudn the layout unprotected. In fact, to avoid messign internally with the computer supply, you can buy mating conenctors, install them on a piece of perf board, and wire in fuses to multiple tapes, each with maybe a 1 or 1.5 amp fuse. Up to maybe 5 amps tops for any single circuit. Conceptually like the breaker panel for your house wiring, high current in, divided into multiple limited circuits.
Is the actual voltage measure of commonj unlimited class 2 supplies taken into account when the TORTOISE maker says to use 9 to 12 V?
Meantime I have both a 12VDC and 9 VDC power supply handy to try with the three tortoises....however, as you know these ordinary household units are unlimited put out more than they state.....The 12 V reads actually 17V on the meter and the 9 V reads actually 16 V on the multimeter.
(Thanks for the input on computer power supplies. I've put them in computers before when rebuilding, but I think that is where I will limit their use.)