Tortoise and DCC voltage level

[Luzhin]

 As I understand it, a Tortoise switch machine works ideally at around 9 volts. Many modelers run their Tortoises off of their DCC track bus, which typically supplies around 15 volts.  Is this all right?  Is there a simple way to use the track bus but lower the voltage coming into the Tortoise?  I have set up an experimental Tortoise (controlled by a Hare, with a bipolar panel light and secondary control provided by a pushbutton) coming off a DCC bus and it works fine, though it is rather noisy.  I'd like to cut the noise some (I understand that is one of the effects of a lower voltage.)  Are the Tortoises likely to be harmed at the higher voltage?  Any input from experienced users would be appreciated.

 Greg

[cacole]

 The only safe way to use the DCC track bus wiring to power a Tortoise is with a stationary decoder such as the North Coast Engineering SwitchIt, which does not put the full DCC track bus voltage to the Tortoise.

The DCC track bus is going to be a high frequency square wave AC which will cause problems with the Tortoise.  A Tortoise requires DC voltage only to function properly.

[jrbernier]

Greg,

  I have not used the 'Hare', but I just installed the 'Rabbit'(same manufacturer) on the club layout.  It is powered from the DCC track bus.  The Tortoise motors move over slow.  The nearby staging yard has Tortoises that are powered by a 15VAC 'wall wart' tha is split into a polarized cconfiguration.  They get about 7.6VDC(half ware) to the Tortoise and move slow as well(about 1 second).  I have not checked the voltage on the 'Rabbit' output to the turnouts, but I doubt if the Tortoise is getting anything close to DCC bus voltage.  It would be 'buzzing' if it got that AC like voltage!  I do not think there is a problem here.  Remember, the track bus voltage into the 'Hare' and the actual 'output' to the Tortoise are two different things!

Jim

[rrinker]

 Actually, I haven't seen anyoen running their Tortoises off the DCC track bus. Not directly anyway - it wouldn;t work very well, although you could do it using the wiring shown in the Tortoise instructions for using 'steering' diodes.

 Now, if you mean via a stationary decoder that happens to get it's power via the track bus - those put out DC on the Tortoise motor leads and the Tortoise is isolated from the track power via the controllign circuitry.

 Either way - not the IDEAL way to do things. You ideally should use a seperate power district for the stationary decoders. That way if you short track power because you run against a turnout set the wrong way - track power goes off when the breaker for that section trips, and if the stationary decoder for that very same turnout is powered fromt he same track bus, you can't operate the Tortoise to fix the problem without first lifting the loco off the track. With a seperate power district for the stationary decoders, you can still operate the Torotise even though power to the track is cut off. As soon as you throw the turnout, the short will clear and you can proceed.

                                         --Randy'