kato dcc decoder on dc

[keitaro]

Quick question if I put the kato clip in decoders on my E5 for example is it going to fry running on DCC or damage train/decoder.


Since I am planning on doing dcc in the future but at this time do not have the room for the rest of layout was thinking may upgrade for ready for future.

Sorry if this has been asked but search for kato dcc and dc brings up a million searches.

[inobu]

Which decoder do you have?

INobu

[keitaro]

i don't have any yet.

but aren't there only a few decoders to use in the E5?

i.e. em13 fl12

not too sure though dcc newbie <-----

[inobu]

Most of the new decoders are Dual mode but vary in how it is set up. Auto sensing verses CV setting and jumper. The one question I cannot find out is how it does the conversion. Before they ran a zero stretching configuration that was hard on the motor. I wonder if they have the decoder passed the DCC circuit all together (if so that's good) but is they are just filtering one signal then it might not be good.

If you get a decoder get a newer one that auto sense (Digitrax makes Kato decoders) it might be your best bet. I don't run dual mode and won't until I find out how they do it.  

Inobu

[keitaro]

i just looked through kato usa site and found the pdf for them very brief info though ....

says will work on analog but may not if does not match the unit

So I guess it will be fine although like you said inobu I'd like to know how this works.

will start searching through for more info on these decoders.

http://www.katousa.com/N/accessories.html

[KenS]

I'm not really clear what your original question was.  Were you asking if you could run an E5 with EM13/FL12 decoders on DC, or were you asking if you could run an E5 with no decoders on DCC.

The Kato decoders are essentially Digitrax decoders, so they ought to work with a normal low-voltage (12-16V) true DC power pack. That "may not work" is probably a warning about high-voltage DC power packs and/or Tomix power packs with "constant lighting" (CL) support, which tends to do bad things to DCC decoders. Just don't use a large-scale (18+ V) or Tomix CL pack and you should be okay. I haven't tested it extensively, but my E5 with decoders works fine with a Kato DC power pack, with one exception: one end always has the headlights lit, and the other end always has the taillights lit, regardless of direction.

I think Inobu's comment was about running the E5 on DCC without decoders, where the command station provides a "zero stretched" DCC signal to operate a DC locomotive, which can be damaging to sensitive motors.  I'd avoid doing that myself, but I don't know for certain if it would cause a problem.

[keitaro]

Awesome thanks kens I was meaning the decoder installed and running off dc 12v w/ simulator 1 amp.

Also I was talking with The Ghan and he mentioned his plans for advanced consists. Having a transponder in both the front and rear and in the motor so he knows when last or first car has left the block.

This interests me. He mentioned using dz-123 decoders.

After reading up about these decoders I can see there were a few function it lacks over say dz-143

Would it be over kill to have one of these in the motor and the others dz-123 and is it worth the extra cost.

[The_Ghan]

Hey Keitaro,

What features is the DZ-123 missing that you need? BEMF?  Probably only BEMF!  If so, you would go for the DZ125.  The DN135D is also pretty economical, and small.

With Cab cars I'm using DZ type decoders instead of TF4, which is a transponding function-only decoder, so that the headlights control remains exactly the same as it would for a DZ decoder installed in a freight loco.

Cheers,

The_Ghan

[keitaro]

Ghan you read my mind.

You would only need that decoder in the motor though and have your suggested ones in the front and back.

And bemf should not affect multiple trains coupled together with push pull syndrome.

As I read you can program it to switch off when coupled.

[keitaro]

Ghan I'm interested in why you are choosing the dz-123 looking through it looks as if the 125 is the same price?

[The_Ghan]

Keitaro,

Two reasons:

1. On ModelTrainStuff the 123 is $4 cheaper than the 125.  I actually bought 3x DZ-123, 3 x DZ125 and 3 x DN135D (the cheapest of the lot at $15.19 each) to test out;

2. Several people here (either the Cap'n or Martijn for one) have had repeated problems with blown DZ125s.

Cheers

The_Ghan

[keitaro]

fair enough was this in tomix models more or just any kind?

[The_Ghan]

Ah,

It was the Cap'n .... here is his post: http://www.jnsforum.com/index.php/topic,4408.msg45543.html#msg45543

Cheers

The_Ghan

[keitaro]

but my E5 with decoders works fine with a Kato DC power pack, with one exception: one end always has the headlights lit, and the other end always has the taillights lit, regardless of direction.

so i installed the decoders and lights do as you say however a strange thing with the motor?

it used to run at 30 on the dial now at 40 it makes a noise like it's trying to do so like a tinging sound softly and at 50% it moves suddenly no gradual speeds is this an issue? or is it just requiring more voltage due to the dcc chip?

I left for about 40 seconds on 40 thinking the decoder may just need time to detect the dc mode but yeah just sits there i had a look and nothing is rubbing from the shaft or anything and taking it out goes back to normal.

I don't want to do damage to motor or or decoder so i think i will leave out decoders till i get my dcc set.

[The_Ghan]

As per my earlier comments about the DZ-125, did you notice the Cap'n having problems again in this thread http://www.jnsforum.com/index.php/topic,393.0.html ?

Cheers,

The_Ghan

[keitaro]

yeah but this is the kato using the kato slip in decoders :D

[KenS]

I've never tried running an EM13 on DC, but I ran one of my DE10s (using a similar-design Digitrax DN163K1D decoder) on DC, using a Kato power pack, for a test recently. And I still had the test rig set up, so I tried it again.  Note that the DE10 motor is of a very similar design to those used on Kato's "DCC Friendly" EMUs (a "three-pole" skewed armature design, with flywheels; different from their older "five pole" straight armature without flywheels design).

What I noticed is that the headlights driven by the decoder come on at about 40% (counting only the "green" band on the throttle knob as 0-100%), the engine tries to move at 50% but stalls immediately, and begins to move at about 60%, but still erratically.  The throttle needs to be advanced to 70% to move reliably, but even then there's a sort of "warble" as the motor seems to be changing speed while it runs.  It's enough to keep me from using any of my DCC-converted trains on a DC supply, although I don't know that it's harmful.  It's just very poor running.

Now in contrast a Kato EF210-100, with the throttle set to 30%, will crawl at a small fraction of the DE10's speed reliably, and with the headlights lit.  I'm not sure it uses the same motor (the EF210 also has a flywheel-equipped motor, but I don't know if it's the new or old design, as Kato has used flywheels on both in their diesels, and I've never taken the EF210 frame apart). But it's a much smoother operation.

It's clear that the decoder does require some kind of minimum voltage to run.  While the EF210 moves at 2.4V, the DE10 doesn't start to move until around 4-4.5V.  That makes some sense, as most logic chips need at least 3V to run (and often 5) and AC-to-DC conversion usually loses 1V.

It's odd that it runs so badly, even once the voltage is sufficient.  I'd guess the decoder is outputting its usual PWM to the motor with a peak equal to track voltage, and at lower voltages this is causing the motor to turn-pause-turn as there isn't enough power in the signal to ride over the long gaps at lower throttle.

[keitaro]

hmm thanks usefeul findings.

i'm keeping them out for now till i get my dcc pack.