CaptainBiggles Posted September 26, 2014 Share Posted September 26, 2014 Yesterday I bought the DCC-ready version of Dapol's new London Transport liveried class 57 pannier (link below) http://Dapol.co.uk/index.php?route=product/product&path=177_59_63_348&product_id=1544 My layout is a small shunting yard so I've been using a Gaugemaster panel-mounted feedback controller, (model UF, here: http://www.gaugemaster.com/panels.html) which works perfectly fine with my older locos. For some (currently unknown) reason the new loco runs very roughly and the LED on the front of the controller flashes/pulses as the loco stutters. At higher speeds it works better. I notice that on the Gaugemaster website it says that Feedback controllers are not suitable for "some DCC-ready", but this is only on certain pages & not in the instructions of the controller. Mixed messages / covering themselves from Gaugemaster? My other Modern, Dapol DCC-ready loco works fine, their Class 121. Different motor / blanking plug perhaps? Has anyone else had problems with feedback & DCC ready locos? A Google doesn't throw up a lot either way. Any advice gratefully received. Joel Link to post Share on other sites More sharing options...
CourthsVeil Posted September 27, 2014 Share Posted September 27, 2014 Hi Joel, afraid, no experience with your loco, no problems at all with the feedback throttles. BUT: the loco in question (per your link) in an N-scale thing, right? Gaugemaster's website states "May not be suitable for use with some DCC ready locomotives." And their .pdf-instructions to model UF say "Not suitable for … poor quality "N" gauge motors." I doubt whether Dapol's N-gauge models have "poor quality" motors, but thyristor driven throttles have a tendency to be not so kind to simple motors... *) Armin edit: *) especially if they are small ! Link to post Share on other sites More sharing options...
Crosland Posted September 27, 2014 Share Posted September 27, 2014 Gaugemaster's website states "May not be suitable for use with some DCC ready locomotives." Someone must have been having a bad day. "DCC Ready", which is just an indication that it has a socket, has absolutely nothing to do with the problem. Andrew Link to post Share on other sites More sharing options...
Oakydoke Posted September 27, 2014 Share Posted September 27, 2014 Someone must have been having a bad day. "DCC Ready", which is just an indication that it has a socket, has absolutely nothing to do with the problem. Andrew As Andrew says, DCC Ready just means there's a socket fitted. The loco is a DC loco. That instruction from Gaugemaster is ridiculous, nonsense even! Link to post Share on other sites More sharing options...
CaptainBiggles Posted September 27, 2014 Author Share Posted September 27, 2014 That was rather my thinking - it's a massively unhelpful comment from Gaugemaster. My understanding was that the blanking plug makes this loco no different to a "DC" loco, and so a bit of clarity from Gaugemaster over what it is that "may" make things unsuitable would be most welcome. For instance, my Dapol 121 runs fine, but my pannier does not. Am I now going to not buy any modern / new locos in case they don't run, and only buy second-hand / old ones? Dapol have been helpful and say it's the same motor as in their Terrier, which has been out for two years and this is an unknown problem for them, so it may be I just have a dodgy loco. But if anyone could explain what "may" make DCC-ready locos unsuitable for my controller I'd be very interested... Link to post Share on other sites More sharing options...
RMweb Premium Izzy Posted September 27, 2014 RMweb Premium Share Posted September 27, 2014 My experience with modern N gauge locos and feedback controllers is that they are not really compatible, and irrespective of whether they are DCC ready or not. Most advice I have read recently seems to confirm my belief by saying that feedback controllers should not be used with today's N gauge. They are fine with the older models using the older design heavier current draw open frame motors, and with some of the new models that continue to use the older motor types, but they cause exactly the effects you describe with the newer, more efficient, and often smaller, can/coreless motors now commonly used. They over-react in just the same way as the current efficient coreless motors always have with DC Feedback (PWM/BEMF). Most of todays DCC decoders use BEMF but at a frequency that is compatible with efficient motors, and of course feedback parameters can be individually 'tuned' to suit each individual motor/loco, which generally can't be undertaken with most DC feedback controllers ( as with everything there are exceptions). So you may be right in your belief that should you wish to continue to use your DC feedback controller then you will have to use it only with locos with older type motors. Izzy Link to post Share on other sites More sharing options...
RMweb Premium kevinlms Posted September 27, 2014 RMweb Premium Share Posted September 27, 2014 Just a thought. Although the box says 'DCC Ready', does by chance the loco actually have a decoder plugged into it? Its always possible that the seller (retailer?), did install one for a customer who then changed his mind, but the seller forgot to take out the chip, or remark the box. Link to post Share on other sites More sharing options...
CaptainBiggles Posted September 29, 2014 Author Share Posted September 29, 2014 That's a really good point re: decodes. I'm going to take the loco back to the shop though so don't really want to be pulling it apart just in case. I can see the pcb in the cab & can't see components though. Yesterday I ran & took videos of three locos running under both standard DC & feedback control. All 3 ran perfectly under DC, and under feedback the oldest loco ran perfectly, the new Dapol 121 ran ok but I think it's mass was smoothing out any jerks, and the pannier was rough as boots. Interestingly the LED on the UF controller pulsed/flashed for both the 121 and pannier. I suspect that whatever it is that Gaugemaster warns about is coming to pass. So, should I change my controller or my locos, that is the question? The feedback does give very good running of old knackered locos at low speed it must be said, would new locos & standard DC give similarly good control? Link to post Share on other sites More sharing options...
Only-Me Posted October 7, 2014 Share Posted October 7, 2014 My experience with feedback controllers is they can damage the can motors which are in most new N Gauge locomotives due to the pulsed signal/frequency they use to create the feedback, irrespective of a DCC chip in them or not... Hence why Gaugemaster recommend you don't use feedback controllers with N gauge locos... Pulsed controllers cause a form of vibration, which may be undetectable to the user, but causes the armature to vibrate in the bearings. For a can motor, this will definitely shorten the life considerably - This pulse is what you are seeing through the can motor and circuitry..... the Dapol 121 & 122 have the older rotary brush motor in them. Link to post Share on other sites More sharing options...
Crosland Posted October 7, 2014 Share Posted October 7, 2014 It's electrical effects that cause damage from pulse supplies, not the mechanical vibration. There are actually two issues. Pulse controllers that deliberately set out to control the motor by pulsing the track voltage and feedback controllers that interrupt the supply periodically to measure the Back EMF (the feedback), thus creating a pulsed waveform. Low frequency pulsing causes excess heating which is detrimental to coreless motors and small motors with very little metal to conduct the heat away from the armature. In the early days of DCC it was not recommended to use decoders with coreless motors, as the decoders used low frequency pulses to drive the motor. All decent DCC decoders these days can use much higher frequencies and are safe for any type of motor. Andrew Link to post Share on other sites More sharing options...
CaptainBiggles Posted October 9, 2014 Author Share Posted October 9, 2014 Thanks for all the info chaps. So, the question remains - keep the loco or keep the controller? Can anyone put my mind at ease and tell me I'll get decent enough running from a non-feedback controller and modern locos? Link to post Share on other sites More sharing options...
RMweb Gold Revolution Mike Posted October 9, 2014 RMweb Gold Share Posted October 9, 2014 Dapol have pretty much said from day one that feedback controllers are not suitable for their locos. A very simple DC controller is often much better with today's locos (eg the one out of the Farish sets). Cheers, Mike Link to post Share on other sites More sharing options...
CaptainBiggles Posted October 9, 2014 Author Share Posted October 9, 2014 Where do they say that Mike? My whole objection is that neither Gaugemaster nor Dapol are particularly definitive about this... Link to post Share on other sites More sharing options...
RMweb Gold Revolution Mike Posted October 9, 2014 RMweb Gold Share Posted October 9, 2014 It used to be on Dapol's (old) website, not sure if it is on the new site. Cheers, Mike Link to post Share on other sites More sharing options...
Popeye Posted November 1, 2014 Share Posted November 1, 2014 Not sure if the OP has sorted the problem but I've just taken delivery of a Dapol DCC Ready Hall, I hooked up a single length of Peco code 55 flexi to a Gaugemaster Walkabout (non feedback) and the loco ran superbly straight out the box. As a trial I then timed how slow it would cover the distance - 3 mins, 49.7 secs! To my mind problem solved, buy a new controller to use with newer locos and get the benefits of the more up-to-date mouldings and motors. As an aside, it was also very quiet despite the track not fixed down but sitting on a desk without any underlay. Hopefully this provide some reassurance and guidance Link to post Share on other sites More sharing options...
Ken Anderson Posted November 2, 2014 Share Posted November 2, 2014 Someone must have been having a bad day. "DCC Ready", which is just an indication that it has a socket, has absolutely nothing to do with the problem. But may have more than just a socket.What is a blanking plug? When is blanking plug not a blanking plug? Are are blanking plugs the same? Link to post Share on other sites More sharing options...
Crosland Posted November 2, 2014 Share Posted November 2, 2014 The blanking plug has no bearing on the problem. With the blanking plug fitted the loco is simply a DC loco. The only reason for incompatibility between a loco and a controller is the waveform from the controller being unsuitable for the motor. If you believe otherwise then please clarify what you think the problem might be. Andrew Link to post Share on other sites More sharing options...
CaptainBiggles Posted November 3, 2014 Author Share Posted November 3, 2014 Thanks for all the help guys. As the OP I can confirm that I've decided to replace the controller so that I can use the newer locos. The reassurance that slow-speed running is good under these circumstances is most welcome, thank you. As for some of the later comments about blanking plugs not being just blanking plugs, I'd heard this too but haven't taken the loco apart to confirm. Worth noting I guess that Dapol only do DCC & DCC-Ready locos, so whatever is on a blanking plug it is unavoidable if you wish to run DC. I appreciate the manufacturers wish to avoid backing themselves into a corner, but the amount of literature on this topic is very poor on both Gaugemaster & Dapol's website. Anyway, anyone want to buy a hardly-used panel-mount feedback controller? ;-) Link to post Share on other sites More sharing options...
Only-Me Posted November 14, 2014 Share Posted November 14, 2014 All that is on the blanking plug is a simple circuit connecting certain pins to certain pins, nothing else... eg 6 pins on an N gauge socket, the blanking plug will just create a route (using pcb circuit) from the pick-ups to the motor and lighting if it exists that is all.. here you go.. Link to post Share on other sites More sharing options...
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