Bachmann Loco Problem with Hornby DCC R8213

[Beermug]

Hi guys.

I'm a newcomer to the model train world so I apologise in advance for any schoolboy errors.

I have a  new R1126 Mixed Freight Train Set which works well. I bought a Bachmann Class 56XX 32-084 loco and a dcc chip 36-555 to run on the layout. I have not been able to get it to run with the Hornby controller. I have taken the loco and chip to two reputable shops where it ran perfectly on a dcc layout (non-Hornby) but when I tried it at home I got no response. The Hornby loco's work perfectly on my layout but the Bachmann refuses to budge. I have tried resetting and reprogramming the loco, which the controller appears to confirm correct settings but there is not a glimmer from the loco. Is there a Horby/Bachmann problem that you know of?  I am in need of your advice.

Thanks

Beermug

[Chrissaf]

Welcome Beermug to the forum,

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The Hornby Select controller is not 100% compliant with the NMRA (National Model Railway Association) DCC standard. Some Bachmann decoders are known to have issues with the Select. Off hand I can't remember if the 36-555 is one of the problem decoders. User RAF96 (located Cyprus) is on the ball regarding what is and what is not compatible. I daresay he will give a response when he sees this post.

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You wrote: I have tried resetting and reprogramming the loco.......

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The Select is incapable of resetting a loco decoder, it cannot write to CV8. The 'resetting' feature documented in the Select manual relates to resetting the Select controller itself, which is something completely different.

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You inferred that you fitted the 36-555 decoder yourself, therefore you know how to do it and what is required. I would suggest replacing the Bachmann 36-555 decoder (get your money back on it if you can) and substitute it with a Hornby R8249 decoder. Mixing Hornby decoders in a Bachmann loco is not a problem. Having the Hornby decoder will ensure interoperability with the Select.

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This Bachmann issue is specific to the R8213 Select controller. This issue is not seen on the other Hornby DCC Controllers Elite R8214 and eLink R8312 (PC required for eLink).

 

[Beermug]

Thanks Chrissaf

That explains a lot.

I'll get a new Hornby chip, give it a go and let you know the result.

Cheers.

[96RAF]

Thanks Chris - your confidence in me is underwhelming.

 

Hornby has made great efforts to get their kit to work with Bachmann decoders by way of updates to the Elite firmware and I can only assume that these decoder variants are not quite fully compatible with NMRA rules and standards. This has also been found with other decoders such as some of the Hattons ones.

 

We know from historical posts on the forums that the Hornby Elite is fully compliant with NMRA as it has been tested and thus certified, and that the Select is not fully compliant, but I have heard that this is just a question of some ringing (?) when idle and not an operational issue and that there is a supposed fix on the e-bay market which installs a choke on the cable to dampen this effect.

 

As Chris says if the issue is with the Select only operating this decoder then his advice to install a Hornby R8249 decoder would also be my advice, as it would prove things one way or the other.

 

Or you could try the e-bay ferrite core 'magic' fix on your Select and let us know if it solves the problem.

 

If you do go down this route please be aware that you can buy the necessary bits from the likes of Maplins or RS Components for a fraction of the cost of this eBay product - he even gives the correct RS part number on his flog-it  post for you to go get.

 

Rob 

[Chrissaf]

For anybody who is interested.

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The 'Choke' solution that RAF96 refers to, is basically a 100uH inductor that goes in series with one leg of the wire pair that goes between the Select and the track - see diagram below.

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/media/tinymce_upload/a28a6206725b9719ab74fa3726f2f74b.jpg

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The 100uH inductor (Choke) needs to be a high current type, so not all 100uH inductors are suitable. The one in the link below is rated at 2.5 Amps (the Select power supply is only 1 Amp) and thus is suitable to use for this alleged solution modification.

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100uH 2.5 Amp Inductor

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Note: This may not be the product the ebay seller is using, but this RS component has been documented elsewhere as suitable. The addition of a 'Choke' to the DCC circuit has been documented several times to offer benefits to the DCC digital signal conditioning of the Select output.

[96RAF]

I wonder how that will fare when the Select is used with the Elite 4 Amp supply Chris.

Anyone like to test it and report back please.

[Chrissaf]

Hence why I specifically mentioned the current rating comments to raise a flag.

[96RAF]

Having trawled the files and asked some questions of people, I can offer more on this subject, but it will ramble on a bit so go and get a cup of tea while I try to get my thoughts together.

 

Hornby Select is NMRA compliant and Elite is NMRA compliant and warranted, in addition to meeting EU EMC regulations over and above NMRA. Therefore they are able to operate most decoders without any problems, however there are known problems with some decoders, even down to which model is a particular decoder fitted to when it plays up e.g. Bachmann Winhoff MPV plays up, but their Class 416 with the same decoder does not.

 

As to the ringing spoken to above, in compromise the Hornby controllers have been 'tuned' to provide very little high frequency ringing on load, but a side effect is some low frequency ringing off load, particularly with the Select and the main reason it gets the NOT NMRA COMPLIANT bad press. The Bachmann 36-series decoders have been shown to be particularly sensitive to low frequency ringing.

 

How do we fix or at least minimise these problems:

 

1. Hornby could 'retune' their controllers by way of hardware fettling but this would mean having to submit to further NMRA checks and I think why should they just to sort out someone else deficiencies.

 

2. Turn off DC running at the controller via the reset or other menu and at the decoder if these options are available.

 

Note that the Select by default has the Loco-0 feature turned ON and the Elite by default has it turned OFF.

Something to check on the Select is have you got Loco-0 set to zero throttle as if it is sending a speed or function command to a Loco that isn't there then it may affect those locos that are on track. So select Loco-0 and make sure speed and any functions are all off.

 

3. Installing a 47Ω high wattage resistor (at least 7W rating) in the feed to the track may resolve any issues re erratic running and control.

 

4. Have several locos on track even if not running as this will place a load on the controller and minimise ringing. You are more likely to have trouble if you only have one loco on track and it has a suspect decoder type.

 

5. The other possible fixes are the choke Chris illustrates above, and also for extensive track runs install track bus terminators that have been well covered elsewhere on the forums (typically a 150Ω 2 watt resistor is connected in series with a 0.1μF ceramic capacitor).

 

Bachmann decoders are not the only ones to play up. Some of theirs are rebadged LokPilot Basic and some are Soundtraxx, TCS usually suffer from EMC problems not the zero bit stretching explained above. Hattons 21 pin decoders have been reported to play up, but later refuted, so possibly these are also rebadged versions already known as problematic. It is well known that several US brand decoders will not play nicely either.

 

The most common reason discovered as to why these decoders won't play nicely with Hornby controllers is intolerance in the way they handle DC loco operations (Loco-0) i.e. the stretched zero bit in the DCC signal used to control analogue locos.

 

In fact some manufacturers manuals specifically say that they do not support DC operations e.g. Bachmann Dynamis and Gaugemaster Prodigy Advance.

 

It is also worth noting than Hornby is not alone in seeing these problems and it has been shown that Lenz LH100 has the same DC running problems with LocPilot decoders, in fact it is possible that any controller with Loco-0 facility could show problems, especially if the controller by mistake has the Loco-0 throttle set for speed regardless of whether such a loco is on track or not.

 

I know this has rambled on a bit but I hope this sheds some light on why some people have seen these problems and others have not and also that I have given some ideas as to how to resolve the problems as far as is possible.

Rob.

[Chrissaf]

Regarding item 5) in the list above. One advantage of the in series Inductor (Choke) over the long track line terminators. Is that the terminators are placed across the DCC signal path and draw current even when no locos are on the track. Typically about 100 to 120mA per terminator. Assuming two are fitted, that equates to reducing the overall power available from a Select 1 Amp power supply by the equivalence of one loco. The in series Inductor (Choke) just passes the current required by the loco onto the track. Thus power consumed by the Inductor (Choke) itself is absolutely minimal and thus doesn't detract from the power supply current available for running locos.

[Rog RJ]

@Raf96

 

Where have you seen that the Select is NMRA compliant?

 

It never has been afaik.

 

[Yelrow]

Raf, think you missed out a not, before compliant for select. john

[96RAF]

Came from the horses mouth John.

Even Select page says it is designed to NMRA standards.

To understand the difference between compliant and warranted you have to delve into the NMRA rules and regs, mostly to do with depth of testing by NMRA, usually driven by the associated cost of such testing.

[Chrissaf]

So Rob, would you be happy that in future, instead of saying:

"The Select is not NMRA compliant"

it was stated instead

"The Select is not NMRA certified"

[96RAF]

So Rob, would you be happy that in future, instead of saying:

"The Select is not NMRA compliant"

it was stated instead

"The Select is not NMRA certified"

 

@Chris

To be absolutely sure of the terminolgy I had to get the NMRA book out and check.

 

The words used are compatability and warranted conformance.

I quote from the book:

 

'...Compatability is currently a manufacturer's opinion (without independant verification) that their products work with conforming products...'

Such products are usually marketed as Compliant with NMRA standards.

 

The Select page says it 'Complies with EMC requirements' another page says designed to NMRA standards.

 

'...Conformance is a formal statement made by the NMRA that indicates to the best of its knowledge a product conforming to the NMRA DCC Standards, Recommended Practices and  agreed upon industry metrics (which are NMRA/industry agreements not covered by NMRA Stds & RPs) ... products passing the NMRA tests are issued a Conformance Warrant and allowed to display the NMRAs football shaped logo...'

 

 

/media/tinymce_upload/d31559c7c962f50006e48c81f51de99e.PNGFootball logo

 

Such products are usually marketed as conforms to all applicable NMRA standards and display the logo.

 

The Elite page says is NMRA Certificated and also that it complies with EMC requirements.

 

So make of that what you will.

[Chrissaf]

I was just thinking that for the forum audience "certified" might be more meaningful than "warranted" and more accurate than "compliant".

[96RAF]

From the above the Select could best be described as Compliant as Hornby designed it to meet NMRA standards, but the Elite is definitely NMRA Conformant as denoted by the football logo and the fact Hornby will have a Conformance Warrant Certificate from NMRA.

[2e0dtoeric]

Chrissaf, I suspect that ALL of us forum audience should be certified - after all we DO play with toy trains!  😛

Back to the subject before someone calls round with a big 'ammer!

[Homer]

I have just had my Elite reprogrammed by Hornby to the latest updates and it will not program the Bachmann MPV unit. I am going to try to program a Bachmann 21 pin chip in a Bachmann class 70 with the Elite so will let you know if it happens.

otherwise I will use the 21 pin to 8 pin adaptor as I cannot justify spending £34.00 + for the Hornby Saffire.

[96RAF]

@homer

Unfortunately the Bachmann MPV is one definitely known not to work well with Hornby kit, whereas their Class 416 with the same brand decoder does work so its a case not only of the decoder but its  combination with the loco eletrics having some affect as well.

 

The simple way to try to get over it is to swap deocders around if you have that flexibility of course and if you are prepared to open your locos - many people are not happy doing this or it may just be outside their skill level.

Rob

[96RAF]

@homer

Unfortunately the Bachmann MPV is one definitely known not to work well with Hornby kit, whereas their Class 416 with the same brand decoder does work so its a case not only of the decoder but its  combination with the loco eletrics having some affect as well.

 

The simple way to try to get over it is to swap deocders around if you have that flexibility of course and if you are prepared to open your locos - many people are not happy doing this or it may just be outside their skill level.

Rob

[Howbi]

Hi Beermug...........As a matter of general interest it would be useful to know if you deliberately chose the 36-555 8-pin 4function decoder because, unless you actually need 4 functions for your 56xx tank engine, ie for front, rear & cab lights and firebox glow, it would seem a strange choice bearing in mind the 3 extra leads off the decoder which you would have to cut off.......the 36-553 decoder would be more suitable if not the Hornby R8249..........HB