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paulmaglev

Cardinal Voltage Rules.

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paulmaglev

The standard rule of thumb for working with Japanese model trains from what I read in the forums is to never exceed 12 volts, does this only apply for N scale J-trains or does this also apply for HO scale J-trains as well?  If so, then I might have some trouble finding a DCC system that is compatible with North American models and J-models.

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kvp

Most N scale trains have 12V motors, but kato motors are 16V tolerant, especially DDC ready sets, like most north american and european prototypes. The same is true for H0 and the stock kato trafo has 12V at the bottom and 16V at the top of its red zone. Tomix and modemo sets are strictly 12V though.

 

For european Fremo N DCC, 12V is also a rule. If you input 15-16V into the booster, you'll get 14V DC at the track and the decoder's bridge and driver gets it down to 12V on the motor outputs. So any DCC system with 14V DCC on the track will be fine. One manufacturer is digitrax who makes fine centers, boosters and decoders for H0, N and Z.

 

Suggested DCC track voltages:

H0: 14-16V

N: 12-14V

Z: 10-12V

(in analog the lower value should be the max.)

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Welshbloke

The DCC decoders convert the 16v AC to 12v DC, so the motor only sees 12v max.

 

Just beware of putting decoder-fitted locos on an analog layout using a PWM controller (as I understand Tomix sell), as apparently decoders don't like it.

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E6系

The DCC decoders convert the 16v AC to 12v DC, so the motor only sees 12v max.

 

Correct.  You will have no problem at all.

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kvp

 

The DCC decoders convert the 16v AC to 12v DC, so the motor only sees 12v max.

The DCC decoders only see a DCC signal and that is a bipolar square wave and can't be measured with an AC or a DC multimeter. The motors see the DCC signal after the diode bridge and motor driver of the decoder, so 16V DCC will usually get you 14V DC to the motors (with a PWM modulation). That is fine for most H0 locomotives, but could damage Tomix H0 motors. Having 14V DCC on the track nets roughly 12V DC (with PWM modulation) on the motors. The voltage drop of a decoder is usually fixed and depend on the parts built into it.

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paulmaglev

This sounds fine and dandy. By extension, would it be safe to say that I won't have to worry about frying the circuit of a dc locomotive if it's equipped with Quantum sound decoder from QSI?

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Welshbloke

Assuming you mean a DCC sound decoder then it's designed for that purpose.

 

I ran Walthers, Bachmann, Athearn and Hornby locos with various motors from a Lenz Compact when I last had a HO/OO layout, never had any trouble. The layout was principally HO, but used to see occasional OO visitors as I've always been prone to buying models I like even if they don't really "fit" the rest of the collection!

 

I have a booster (branded as Bachmann, not sure who made them) which I used to run G scale with the Compact, as 2.5A won't get you far when you want to run a twin-motored railcar hauling three coaches with interior lighting. That has a switch to select 16v or 18v, so it could safely be used for any scale.

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paulmaglev

I guess the Quantum sound decoder is DCC like all the decoders QSI sells on their retail site, but I'm not sure.  The locomotive I'm looking at (a die-cast C62 Sanyo) from Tenshodo has a description that is short and ambiguously translated by Google, omitting details like the name of the decoder. Maybe I'm over analyzing this, but I can't make heads or tails about what Tenshodo is trying to tell me in its website since the majority of their products are DC only while QSI tailors to DCC control.

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kvp

There are analog and multi mode sound decoders. Analog decoders have to be replaced, while analog/DCC decoders can be used on both systems. Many soundless DCC decoders also have an analog fallback option, so if they see less than 12V on the tracks, they switch to analog mode, while above 12V, they expect the DCC packets. This is one of the reasons digital Fremo N requires DCC voltages between 12 and 14V. Most centers and boosters have selectable voltages between 12, 14, 16, 18V (Z, N/TT, H0, 0/1/G).

 

I would add that some older east german and italian 0 scale trains are strictly 12V only, some N scale models are equipped with low voltage motors that can't even tolerate a 12V pwm controller and some Z scale DCC decoders can run on DCC voltages as low as 7-9V.

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paulmaglev

There are analog and multi mode sound decoders. Analog decoders have to be replaced, while analog/DCC decoders can be used on both systems. Many soundless DCC decoders also have an analog fallback option, so if they see less than 12V on the tracks, they switch to analog mode, while above 12V, they expect the DCC packets. This is one of the reasons digital Fremo N requires DCC voltages between 12 and 14V. Most centers and boosters have selectable voltages between 12, 14, 16, 18V (Z, N/TT, H0, 0/1/G).

 

I would add that some older east german and italian 0 scale trains are strictly 12V only, some N scale models are equipped with low voltage motors that can't even tolerate a 12V pwm controller and some Z scale DCC decoders can run on DCC voltages as low as 7-9V.

 

This helpful information is enlightening.  I've done some more research and found a DCC controller I can use and everything should be good to go.  Only one question remains unanswered: what type of decoder lies within the Tenshodo's C62 Sanyo?

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