Large Scale Central

Zimo MX695KN smoke chuffing

Electronics DCC
#1

In my quest to accomplish satisfactory smoke chuffing for my Hudson, I bought a Zimo MX695KN, which has both fan and heater control with BEMF braking on the fan. I plan to pair this with a AirWire Convrtr. I got everything laid out to start assembling it, and discovered that, along with the sound outputs, the cam sensor input on the KN version (no sound) has been removed. Since I’m using a Phoenix sound module, I really need to be able to control the smoke chuff with the cam sensor so it’s synced with the sound. I can’t use their “virtual cam sensor”

Does anyone know if this decoder will accept a cam input somehow?

I called Train-Li, and got an answering service.

#2

We will wait for Greg or Dan on this one…(https://www.largescalecentral.com/externals/tinymce/plugins/emoticons/img/smiley-laughing.gif)

#3

So you tried In3 and it won’t trigger?

Of course you picked a decoder with the “no sound” option and then are miffed it does not have a chuff input. You gotta think like us (1/4) Germans, why do you need a chuff switch when you have no chuff sound? Schweinhund! (said in joking manner)

Actually did you find a statement where it says that input is ignored? Perhaps you have not unmuted the sound (by default all sounds are off and you have to hit the F8 to get them to start, perhaps the chuff/fan output is controlled there?

Greg

#4

I haven’t tried anything yet, because I have a feeling I’m going to be returning this unit.

This board does not have sound, but it’s the same footprint as the version that does. They used they shorter bank of screw terminals, and the sound outputs, along with IN 3, are not populated, making me think that IN 3 probably doesn’t do anything.

I’m not sure what you mean about in muting the sound, as sound isn’t supported on this board. For the version of the board that does support sound, there is a CV that selects between a real or virtual cam sensor, but there is no mention of smoke in that section, and no mention of IN 3 in the smoke instructions.

#5

So, even though the system has no sound, perhaps the chuff input would be ignored if the “sound” was still muted…

In3 is on the connection diagram for the chuff switch.

I’ll bet there are traces to where the In3 terminal would be though… you could give it a try… I read the manual, it does state that the version you have supports the heater and modulated fan. If you are worried about the heater/fan support, program it up like a diesel and see if the fan and heater function.

If it was me, I would buy the full blown unit, what is the incremental cost? Less than the sound unit you are using I would guess (https://www.largescalecentral.com/externals/tinymce/plugins/emoticons/img/smiley-cool.gif)

Greg

#6

I’m not worried that the heater/fan support isn’t there. I’m confident that it is. What I’m worried about is not having the option to trigger it externally. The manual is pretty clear that they recommend using their virtual cam sensor over a real one.

I missed callback from Train-Li last night, so I hope to talk with them today. I don’t want to solder anything to the board if I’m going to return it.

I considered getting the full version, but that’s another whole sound ecosystem that I don’t want to deal with, since I already have the programming hardware for Phoenix.

#7

I guess I am just doing a crappy job of communicating.

Use the “pulsing fan” support to test the chuff input on In3 (at least the trace where the connector would go.)

Clearly do not solder, stick something in the hole even tape or just take a grounded wire and tap it on the hole/trace (simulating the chuff switch)

I doubt anyone at Train-Li has tried this, maybe Dan Pierce knows…

Anyway, if I am still unclear on my suggestion, let me know, I am trying to help…

Greg

#8

Thanks, Greg. I know you are

I got a definitive answer from Zimo:

That is correct, IN3 (input 3) is only available via solder pad, but that shall not be real issues (We simple save some money with the shorter screw terminal, as in case of the MX695KN it is quite unlikely, that someone uses these 4 connection - speaker, second motor-, IN3).

Yes, you can connect your CAM sensor to IN3 (please also set CV#268!) and the ventilator impulses will be then put out on Venti1 output (special fan connection, first connection of the third screw terminal).

#9

Yep, expected that, no way they made a different board, and highly doubtful they would make different firmware… so you get a bargain!

you could always solder a small socket or something in that hole…

Let us know your progress…

Greg

#10

CV 268 does select in3 if greater than zero.

CV 351-355 are the fan settings, 351 cruise, 352 load/max accel, 355 idle.

Also heater element is 137-139, idle, cruise, acel/load.

Note that for all this to work, the cv between 125 to 132 must have the heater function key set to 72 for steam, 80 for diesel. that is heater on F6 then cv132 needs to be 72.

#11

That’s great info Dan, I noticed from reading the manual there were a bunch of diesel/steam settings… with your permission, I’ll document those tips on my site

Greg

#12

Please do document these settings. Next should be the uncoupling via servo info plus waltz programming.

The waltz is the way that at press of the decoupling key, the decoder takes over and will slowly open the coupler while slowly backing up, stops and then pulls forward away from the car.

#13

I’m going to ask this here, since it’s already been buried in my Hudson build thread.

I have the Zimo MX695KN working as planned, triggering off of the cam sensor (actually through an optoisolator, but same thing), and it’s working great. However, when the smoke is on, the lights connected to the other function outputs randomly turn on and off. See video below. My suspicion is that it’s a too-much-current issue, but I don’t think my total adds up to the 2A limit. The smoke heater is a little over 1 A, the fan is 125 mA or so, and the headlight is exactly 20 mA (LED with CL2N3). I should have plenty of headroom.

If I turn off the heater (I put a switch inline for hard disconnect), the light stays on.

#14

It really seems that somehow your LED is set up for something strange… not the fan or heater, but something like firebox flicker…

You need to look at what output the headlight is tied to and investigate if there are other functions tied there… better personally inspect the headlight wiring too…

That is crazy…

#15

Eric,

With all the changes you have made I have lost track of things. Could you put up a list of the major components you are using for motor drive, sound etc?

#16

Zimo DCC decoder and Zimo smoke unit (which looks similar to Aristo) Visaton speaker…

I think he mentions the model number of the decoder, the MX6** series… the low cost one with fewer screw terminals.

Greg

#17

The setup is a 18 V battery feeding an AirWire Convrtr (6 A version), feeding the Zimo decoder. A Phoenix P8 is also connected to the DCC outputs on the Convrtr. The cam sensor is driving a pair of optoisolators, one of which is connected to the trigger on the Zimo and the other on the P8. So there is no common electrical connection between the boards other than the DCC input.

The outputs from the decoder are nothing fancy. Headlights are both connected to their assigned terminals, and other lights are on F0x outputs (classification, markers, cab). The lights are all LEDs with CL2N3s in series, connected to the common V+ (full rectified DCC voltage). Smoke fan is on the special fan terminal, and smoke heater is on F08. F08 is the only output that is programmed for an effect, which is steam smoke.

Notes that may be helpful:

  1. This issue affects all lights (headlights (front and rear), cab light, classification lights, marker lights). It is not a lighting effect inadvertently selected on the headlight output.

  2. The problem goes away (lights stay on), when the smoke unit heater is disconnected. I have a switch between the heater element and the F08 terminal, and can open the circuit, even though the decoder is unaware of the change.

  3. The manual indicates that if excess current is drawn, the decoder will attempt to reboot, and this may lead to flashing lights. I would assume, though, that it would also lead to the motor stopping, and the chuffing of the fan stopping, but neither of these is happening.

  4. I don’t yet know whether the heater is also turning off with the lights. I’ll open it up and test this.

#18

Could the battery voltage be dipping and confusing the Zimo?

Could the heater be spiking at more then an amp after it warms up, or when the fluid level drops a bit?

#19

I thought of the fluid level possibility, but it happens even when there is plenty of fluid. It also happens continuously (on and off and on and off) if I run at a constant speed for several minutes. Nothing under that condition is changing/spiking.

I think the correct way to handle this is to connect the heater directly to the battery, and isolate it from the decoder with an external MOSFET. That way, it’s not drawing that current through the decoder or Convrtr. Of course I’ll have to optoisolate it since the ground isn’t common between them.

#20

The lights should be connected to a low voltage supply on this decoder and the smoke to the variable voltage which should be set to 15 volts. This will isolate the heater element from the lights.

If you set up a dimming in cv60 then you need to not dim the smoke unit in cv 114.