Sierra shuts down

maxi-model

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I've recently converted 3 x Bachmann locos (see posts passim), to battry/RC/sound. I have used some old Sierra cards to provide the sound functions. All locos have the Bachmann PnP PCB architecture - 2 x K-27's, 1 x Mk II Climax. The installations are essentially identical - they all use the same RCS supplied equipment set ups - their Batt PnP wiring loom to the PCB, 16.8v NiMH battery packs, RCS branded, Micron derived, RC kit and switches, Fosworks Cobra 260 (100 watt) ESC. The set up also includes the RCS SSI-9 device that both supplies PWM current from the ESC converted to linear for the Sierra sound card voltage activate sounds and a regulated voltage supply for the "stay alive" functions. The 3 Sierra cards used are - Standard steam ( the one with a problem), K-37 and Climax versions. All 3 use the factory fitted on board triggers to activate the chuffs.

Problem - all 3 seemed to run fine until one (only), the "standard steam" installed in a K-27, started shutting down after about 4 minutes of operation out on my line. Switch off and on again and it works again for about 4 minutes then shuts down again. and so on. I've not put the stop watch on it. The loco's electrics, speed and lighting, otherwise perform normally. I did a full recharge on the battery and the problem persisted. The issue did not show up when test running on rollers, but then I never gave it any long runs on there. Both K-27's are fitted with a fix for the chuff inversion issues they are known for. I have yet to try a full factory reset on this card to start again to see if that might clear a possible glitch that has occurred. The other two, and a previously converted Accucraft loco with a Sierra, all work reliably.

Any ideas what may be happening here ? Max
 

PhilP

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I assume this is when running, and not the card shutting down on idle?

Immediate thought would be possibly heat build - up?

PhilP
 

maxi-model

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I assume this is when running, and not the card shutting down on idle?

Immediate thought would be possibly heat build - up?

PhilP

While running not at idle, I think, I have not sat it at idle for any time. An identical installation in another Bachmann K-27 is not similarly afflicted. I will try running it with the top of the tender (coal load) removed and also sitting it at idle for a while and see what happens. The Sierra is set at the top of a stack of kit, all separated, to allow ease of access to its "controls".
 

Fred2179G

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started shutting down after about 4 minutes
My EBT #15 had an old Sierra system, and it shut down after a short while. A stop and start always got it going. The loco was battery powered and had quite a big speaker. It turned out that the Sierra doesn't like high volumes, and will turn itself off if you overload the amplifier.

Turn the colume down on your problem loco and see if that clears it up. If it does, re-engineer the speaker install with a more-efficient speaker in a better enclosure?
 

maxi-model

UK/US/ROW steam narrow gauge railways 1:1
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My EBT #15 had an old Sierra system, and it shut down after a short while. A stop and start always got it going. The loco was battery powered and had quite a big speaker. It turned out that the Sierra doesn't like high volumes, and will turn itself off if you overload the amplifier.

Turn the colume down on your problem loco and see if that clears it up. If it does, re-engineer the speaker install with a more-efficient speaker in a better enclosure?

Thank you Fred I'll give it a try within the limitations outlined. I always run at just about the lowest volume I can, about 2 ticks off silent. I use a Vistaton 8 ohm 66.5 x 66.5 x 37mm speaker in this and the other Bachmann K-27 I converted at the same time - Might this be an issue, despite the fact it works fine in the other K-27 ? To all intents and purposes the installations are identical. The only variation is the version of the Sierra card used - the problematic one has the "standard steam" version, the other the "K-37". Max
 

maxi-model

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I would definitely try a different speaker. That one could be defective, or mislabeled.

Interesting you should say that. I had the same thought, provoked by your previous post, as in, "hmm, what if ". I had just assumed as I had ordered 2 x 8 ohm speakers for this project, (the Climax has the factory fitted speaker) and from a reliable supplier, is that what I was sent. I never checked the lables before installing. I have just checked the speaker( removed the enclosure I had made),, this morning - it is labled as 8 ohm, not 4. Do Vistaton have issues there with mislabeling?. Is there a way to check if mislabelled? As in how could I apply a multimeter to it ?

I will give the loco an extended run on the rollers and see what happens now. I'll try it with the coal load out and at the lowest practical volume setting. If it persists I will try a full factory reset and see if that clears the problem. Remember, another Bachmann K-27 was converted in an identical manner, apart from the Sierra steam sound version installed on the same card type.

The other thing that has me scratching my head is that it does not give the automatic double whistle toot going forward, single when stopped and three when reversing. The lighting works as it should going forward and reverse. Also the "grade cossing" whistle effect, activated by an rc switch only gives a single toot when pressed. The bell, also activated by an RC switch rings the times sequence as it should. The other Bachmann K-27 (and Accucraft) and Climax Sierra equipped all work perfectly. So I think a factory reset is in order anyway in case the unit is scrambled in any way, either by faulty programming or conflicting setups. I hope I do not have a failing sound card.
 

Greg Elmassian

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Just to avoid misunderstanding, you are running a single 8 ohm speaker from the Sierra (I think you ordered 2 speakers total for a total of 2 locos)...

So, there is resistance and impedance. They both use ohms as a unit but they are measured differently. You cannot measure impedance with your equipment, it is basically resistance at a specified frequency, and the 8 ohm impedance is a nominal value over a specified frequency range. 8 ohm speakers will typically measure under 8, often around 6.... 4 ohm speakers 2.5 to 3.... again TYPICALLY...

I have never had a mislabelled Visaton (not Vistaton) speaker, and I have ordered at least 40 of them personally.

The Sierras are somewhat programmable, but some features seem to be tied to software versions too, I am not a sierra expert, but I do know one.

Greg
 

maxi-model

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Just to avoid misunderstanding, you are running a single 8 ohm speaker from the Sierra (I think you ordered 2 speakers total for a total of 2 locos)...

So, there is resistance and impedance. They both use ohms as a unit but they are measured differently. You cannot measure impedance with your equipment, it is basically resistance at a specified frequency, and the 8 ohm impedance is a nominal value over a specified frequency range. 8 ohm speakers will typically measure under 8, often around 6.... 4 ohm speakers 2.5 to 3.... again TYPICALLY...

I have never had a mislabelled Visaton (not Vistaton) speaker, and I have ordered at least 40 of them personally.

The Sierras are somewhat programmable, but some features seem to be tied to software versions too, I am not a sierra expert, but I do know one.

Greg

Thanks for the information. Yes, it's 1 x Visaton 8 ohm speaker per loco. I can get the supplier to check it if all else fails. I'll progress and test as stated and see what happens. Not at the top of my list of things to do, as I have 2 other fully functioning K-27's (lucky me) and a loco on the bench screaming to be built (even luckier me). A case of methodically working through it all. I am looking at ESU units for 6 other conversions, not cheap but sound good and with the right sound library available. If I cannot resolve the issue I might switch to one of those.The MLS Premium I have used so far on further conversions is proving a little disappointing to my ears (I just can't get it to sound right whatever I do) Perhaps I am expecting too much. But then you only get what you pay for.

I'm wondering if the RCS SSI-9 fitted might have an issue somewhere perhaps that might be contributing to this issue. I'll check what voltages it is outputting for the "stay alive" functions from the 16.8 v battery pack. I assume the PWM to linear current converter is doing its job. I have some DC- DC adjustable voltage regulators (please do not take me to task on the terminology and the odd proofing errors please) that I can place inline if the SSI-9 is over delivering (now I am way above my pay grade here) Max.
 

Greg Elmassian

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There could be a lot of issues, like I said I'm not a Sierra expert, but I just got off the phone with one.

There is a thermal overload shutdown circuit in the audio amp... and the manual specifically lists that as one symptom of sound cutting out.

The SSI-9 should be putting out under 9 volts.

Your Sierra was designed to work at 12 volts, so your 16.8 volt battery may be too hot, see the manual about this, they recommend dropping resistors, there is a table of values.

Also when you program a Sierra to handle a "trigger input" (and not going over 5 volts by the way on the input), some of the automated sounds go away.

It's very easy to linger on the volume up/down switch and mistakenly enter programming mode, a very common mistake.

Here's some more information, mostly gleaned from one the the experts:

Greg
 

maxi-model

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There could be a lot of issues, like I said I'm not a Sierra expert, but I just got off the phone with one.

There is a thermal overload shutdown circuit in the audio amp... and the manual specifically lists that as one symptom of sound cutting out.

The SSI-9 should be putting out under 9 volts.

Your Sierra was designed to work at 12 volts, so your 16.8 volt battery may be too hot, see the manual about this, they recommend dropping resistors, there is a table of values.

Also when you program a Sierra to handle a "trigger input" (and not going over 5 volts by the way on the input), some of the automated sounds go away.

It's very easy to linger on the volume up/down switch and mistakenly enter programming mode, a very common mistake.

Here's some more information, mostly gleaned from one the the experts:

Greg

Thank you Greg. I'll take a while to read through the link. All four of mine seem to be V3 - 4 holes. Might come back to you for that PDF. Yes, after programming 4 old Sierras so far (nothing more in the pipeline) there has been a little finger trouble at times. I usually spot it in time. The fact that some of the automated sounds have gone away on this one, and not on the others, suggests there might be a self inflicted programming issue here.

So, first step is a factory reset and then reprogram, carefully, to my preferred "standard" settings. All 4 of my Sierras are battery powered with ESC variable voltage for the motor, chuff non voltage trigger operation and 3 RC triggered sounds. Then run a test, under load, with enough time to let a the fault show up. If that fails I'll look at what is coming out of the SSI-9 and dial that down,, if there is an issue with a DC-DC buck converter on the output side (is that viable ?)

In the end it is an old card and I knew the risks when I bought them. Just have to be pragmatic and move on if it is a "terminal" fault. Max
 

Greg Elmassian

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Interesting, you should be able to eliminate the optocouplers on a steamer if you use a chuff trigger... but you said "chuff non voltage trigger"... we usually say either triggered or "autochuff".... so I'm not sure which you mean since you say "non voltage" and "trigger" in the same sentence.

But in any case the voltage going to the "battery" inputs needs to be less than 12 volts for sure, so you need that regulated supply.

I'd read my page and see if that helps. If you have more questions, the guy I work with is probably the #1 expert on this in the USA and I can get his help.

Greg
 

maxi-model

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Interesting, you should be able to eliminate the optocouplers on a steamer if you use a chuff trigger... but you said "chuff non voltage trigger"... we usually say either triggered or "autochuff".... so I'm not sure which you mean since you say "non voltage" and "trigger" in the same sentence.

But in any case the voltage going to the "battery" inputs needs to be less than 12 volts for sure, so you need that regulated supply.

I'd read my page and see if that helps. If you have more questions, the guy I work with is probably the #1 expert on this in the USA and I can get his help.

Greg
"Chuff non voltage trigger" = another way of saying I am using the K-27's on board triggers - With an RCS supplied device on the Bachmann main PCB, bridging J1-5 & 7 terminals - to eliminate the K-27's "chuff inversion" issue. And there I was thinking I was making it all clearer. Silly me. This Sierra, as are the others. is programmed for triggered operation of chuff not "autochuff". I assume that setting locks out the subsidiary functions attached to "autochuff" operation. But I will do the factory reset to try eliminate any gremlins that might have crept in there - let's not assume anything - default is triggered operation. It's interesting if the card is getting both inputs, don't ask me how I know ;) I have done that programming mistake on all 4 Sierras I have, so I do not think any permanent damage was done there to contribute/promote to this particular issue.

Could you tell me where an optocoupler fits in please, and what they are in layman's terms ? It's a device I hear of often but do not understand. I will indeed read the page you have sent the link to fully. Now I have to get down to doing the rudiments suggested and that come to mind as detailed and report back with a go/no go (just watched the film "Hidden figures"). Max
 

Greg Elmassian

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Thanks for explaining... just a hint, when talking to someone from the us, you either mention you are using the chuff "switch" (whether is it electronic or mechanical can be inferred by the model and make and sometimes the version).

The K-27 inversion issue is well known, I have personally argued with the guy who tried to change the standard... notice subsequent locos have no such foolishness...

Yes, reset the Sierra first, absolutely. From what I understand there are some limitations in capability, like the automated sounds that go away if you trigger sounds, I'll try to increase the content of my web page. I'm pretty sure automated grade crossing is one of the things you give up. There's some terminology I need to add to my page.

In reference to your last question, I have put considerable effort into my web site, which has 750 individual pages, and about 12 million hits. Please read the Sierra page first... your last question is answered pretty much, because while I used optocoupler as a convenient term, the circuit does more than just electrically isolate, there are 3 factors at work here that need to be addressed and the board solves all 3. Actually the use of the optocoupler is misleading, read my page.

(an optocoupler basically uses optics (opto) to couple (coupler) electrical devices... just like fiber optics can do... but that does not explain everything. As you read the page, the issues addressed are explained, and if I don't do a good job, then your feedback will help me improve the page, notice that page alone has been accessed 8,000 times.

Greg
 
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maxi-model

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Greg, you do not need to impress on me the value and veracity of the content of your website, we are on the same page there. I've had a quick scan through of the link you provided and have bookmarked, as previously stated,.for perusal at a good time. There is an awful lot of information on your site but the relevent bits do not always leap out at you. I usually try to adapt my vernacular to what predoninates in the forum I am on, if conversant. However, we are a pretty broad based bunch here, not just UK centric. And as you and many others may have realised by now I am not that au fait with a lot of electrical technological terminology, I am very upfront about that. But I am not without my abilities. Anyhow it's the National 16 mm NGM show this weekend - must leave debit card at home, must leave...... Max
 

beavercreek

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Hi Max
I have found the sierra cards pretty tolerant to voltage. In fact they work off up to 22V DC when using track power.
I have not had a card misbehave from track power except for when the back up battery was low or knackered. As you are not using track power and have no need of a backup battery this might not be relevant except that the card can handle your battery power voltage happily.
Your battery system with the Sierras is quite complicated, in a way, but definitely works as your other Sierra equipped locos attest to.
Although a complete reset may well work to stop the '4minute' shutdown, the symptom does seem to be more of a threshold over-reach (like amplifier overheat etc).
It may be another component in your RC system overheating. Perhaps a finger test on all of your boards and components while on your rolling road might give an indication of one (or more) heat source.
 

Greg Elmassian

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I just updated my page, it seems that there are some real tricks to the grade crossing operation.... You may want to revisit you settings for Step 14 in the manual and also read some of the notes on it on page 27.

I just spent 2 hours with my friend getting the information on the Sierra much better.... finally answered some questions I have had forever...

Mike, just to avoid confusion, it's the max voltage on the battery terminals that has a strict limit, not the the track pickup input limits, my information is that 24 volts seems to be ok, but SoundTraxx is famous for lack of specs.

Max, please take this the right way: on the terminology, since you have a USA built sound card and an American English manual on an American loco, I would stay with American terminology if you want the most help from the most people would be my advice.

Also a note on my web site; the home page states:

Welcome to my web site! The purpose of this site is twofold, to be an information repository for myself and to share with others. The goal is not to copy what is out there, but to provide supplemental or corrected or missing information, and to share things I have learned on how to use / fix / improve things.

So, my site rarely has any "cookbook" or by the numbers stuff, I cannot possibly have start to finish complete recipes for beginners, so perhaps that is part of the issue where things do not leap out at you.

I have a philosophy that you should learn the basics before trying advanced stuff, and many people want to bypass that... which is their right and choice, but then my site might be frustrating to people who want to work on sophisticated circuits but don't want to understand Ohms law. Just like my position on people who want to program individual CV's but refuse to understand base 2 math.

It might sound unfriendly, but I don't have the time to make every part a complete tutorial from start to finish. (read the red part again please).

Anyway, you see I am working hard to help you.

Greg
 
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