jacksprat. Posted May 7, 2014 Share Posted May 7, 2014 Hi I have just changed a R 8249 decoder and installed a Sapphire I did this because the loco ran very slowly in dcc but not in dc. The loco in question is BR class 37 diesel R369 with the new sapphire in place the select controller will not connect to loco when programming the select flashes 8 times each time I try. I have wired the decoder the same colour coding as the old chip. 2 questions, one have I wired it right? Why wont the loco accept the new address. Any info would be appreciated. Link to comment Share on other sites More sharing options...
Fishmanoz Posted May 7, 2014 Share Posted May 7, 2014 The correct wiring is decoder red and black to the pickups and orange and grey to the motor. The decoder should run on first installation on address 003. Unless of course it is second hand and has been set to an address above 60, in which case your Select can't operate it. Just a final point - given the 8249 was running it, even if slow, it is unlikely the 8245 will do any different. Link to comment Share on other sites More sharing options...
The son of Triangman Posted May 7, 2014 Share Posted May 7, 2014 Good advice there. Another thing to consider is just how well a loco runs under DC before conversion. It is always best to clean and service a loco before conversion. DCC will show every running fault up with a loco. You say it ran faster on DC, this suggests dirty contacts, wheels or a magnet or armature fault as it should run just as well if not better with a new decoder in it. Link to comment Share on other sites More sharing options...
The son of Triangman Posted May 7, 2014 Share Posted May 7, 2014 The select is limited in what it can do as well, as has been mentioned if the decoder address is out of the range of the select then it won't address it with a new address. Link to comment Share on other sites More sharing options...
jacksprat. Posted May 7, 2014 Author Share Posted May 7, 2014 The son of Triangman said: The select is limited in what it can do as well, as has been mentioned if the decoder address is out of the range of the select then it won't address it with a new address. Link to comment Share on other sites More sharing options...
jacksprat. Posted May 7, 2014 Author Share Posted May 7, 2014 The son of Triangman said: The select is limited in what it can do as well, as has been mentioned if the decoder address is out of the range of the select then it won't address it with a new address. Thank you both for your replies the decoder was purchased brand new and I have wired it the correct way but it will not accept an address, every time I try to put in the number I want it to have the select flashes 8 times I have converted 6 other engines all with no problem, the track I am coding it on is very clean and wheels have been cleaned engine was stripped and serviced and has only run approximately 2 hours since then but for some reason I cant fathom out the sapphire wont code. Any more suggestions please. Link to comment Share on other sites More sharing options...
Augustus Caesar Posted May 8, 2014 Share Posted May 8, 2014 Ok... so it's not dirty track or wheels and the motor has been serviced. It ran better on DC as opposed to DCC with either decoder. The problem here is that both decoders cannot be faulty or, rather, are unlikely to be so. You have checked the wiring and all seems ok except you do not say if you have maybe checked for any shorts in the wiring. This could be something easily missed so is worth a check. However, a short with two decoders seems unlikely. Check the decoders in another converted loco to confirm smooth running. Once done and you prove they will reprogram then the loco must be at fault. Even go as far as placing a good decoder you know is working ok into the offending loco and this will definitely prove the loco to be at fault. Once this is determined then you should be looking at poor contacts electrically either on the wheels or the motor. I have converted the same loco to DCC and it runs superbly. Not this helps except to say it can be done. Try each step above and eliminate each area of concern and if it STILL doesn't work get back to us and I am someone can move this on for you. Each step or problem area has to be eliminated first in order for us to guide you more effectively. These steps may help solve your problem but if not they will save you wasting time trying to figure it out and missing something like this that might help. Hope you get it sorted... Link to comment Share on other sites More sharing options...
The son of Triangman Posted May 8, 2014 Share Posted May 8, 2014 A step by step approach is required I agree. I also agree two different decoders aren't likely to be faulty, the odds are massive for that to happen. The track is clean the loco has been serviced and stripped down, that leaves contacts, wring, armature coils and field magnet. Also brushes can give trouble as well, what state are the motor brushes and the retaining springs in, lack of spring tension can cause trouble as can brushes that are effected by oil or have built up a film over the carbon end that touches the commutator from disuse. I had an old class 25 that no one could get going, all was in roder, a good motor with good magnet, good contacts and wiring, clean commutator etc etc. A light application of a fine abrasive to the motor brushes at the end that touches the commutator got it working and it worked a treat after that. Also worth considering is that decoders should be fitted using anti-static handling equipment as static electricity can damage decoders. Link to comment Share on other sites More sharing options...
The son of Triangman Posted May 8, 2014 Share Posted May 8, 2014 Make a check list and work through it slowly, one section at a time, testing, checking. Check wiring and connections. DCC is more fussy than DC and things have to be spot on for it to work at it's best. Also check for electrical shorts as well Did you insulated the cast pin on the motor casting that touches one motor brush holder contact, the contact is the one that had the small black continuity wire that runs from casting to contact. There is usually a small cast pin that makes a contact underneath that side brush holder. This pin must not make contact. have you removed the continuity wire? Link to comment Share on other sites More sharing options...
The son of Triangman Posted May 8, 2014 Share Posted May 8, 2014 Lots of things to check Link to comment Share on other sites More sharing options...
Fishmanoz Posted May 8, 2014 Share Posted May 8, 2014 Simple question to answer for a start - I know you can't change the ID but does it run on the default 003 ID it comes with? If so, does it run slowly as with the 8249, or does it run at normal speed? Link to comment Share on other sites More sharing options...
jacksprat. Posted May 8, 2014 Author Share Posted May 8, 2014 Wow!! so many answers so much information, thank you to all of you for your input I am truly grateful, I did manage to get the loco going on the default code 03 and I then tried again to recode it and this time it worked although it still only goes slowly, it is faster forward than reverse.I haven't checked the motor as thoroughly as you suggest but I will, the contact pin you mentioned I cannot find I am either looking in the wrong place or I haven't got one. The loco was wired as follows before I converted it from the front of the motor a black lead with a spade fitting on each end one end from the pick up the other to the motor, rear of motor there is a brown wire again a spade fitting on both ends one to the other side of the motor and the other end to the rear bogey I have left the suppressor in place should I have removed it? would this make a difference? on the other conversions I have done I have left the suppressor in place. Again many thanks for you help I am feeling my way through the DCC nightmare and still building the layout coming across different problems and sorting them but this loco is driving me up the wall, again thank you to all of you Link to comment Share on other sites More sharing options...
Fishmanoz Posted May 8, 2014 Share Posted May 8, 2014 The fact it is running at all means you have done the wiring correctly. On the suppressor, there is no need to leave it there as the decoders contain their own suppression. I don't think it should cause slow running but worth removing to see. Not surprised it is still running slowly. As I think both I and SoT have said, this is far more likely to be a loco issue then a decoder issue. And the fact it is doing it with both decoders pretty much confirms it. Link to comment Share on other sites More sharing options...
Augustus Caesar Posted May 9, 2014 Share Posted May 9, 2014 The loco was running OK on DC and slowed down on DCC it was stated. There MAY be an issue with both decoders from the point of view that the motor is not getting enough juice through them. Of course that's a motor problem but at least it points to both giving a hint that the loco motor isn't picking up enough power to get the thing running at the speed etc that was stated to be achieved on DC. The suppressor can also be an issue. I have one where I had forgotten about taking that thing off the motor (a Ringfield type) and it slowed the loco down. I can't say it did it one way more than the other in terms of reverse or forward direction though. I just can't remember. If brushes, or maybe other motor parts, were the issue I would have thought that operation in DC may have been affected. Quite literally any one of a ton of reasons may be to blame here. But as said earlier by others a good solid clean out and, from myself, good soldering to connect the decoder wires is essential anyway. Once all this stuff is sorted you SHOULD have a good running loco. If not pop back in and we can narrow it further. The guys on here have given so much advice to myself and others you will have no shortage of it yourself. Each of us have their own level of knowledge but we don't get posessive about it so always feel free to ask. Link to comment Share on other sites More sharing options...
Graskie Posted May 9, 2014 Share Posted May 9, 2014 My own level of knowledge gets less every day nowadays. Link to comment Share on other sites More sharing options...
poliss Posted May 9, 2014 Share Posted May 9, 2014 How slow is very slow? Locos fitted with decoders usually have a lower top speed than DC powered locos. This is because DC controllers usually put out a lot more than the 12v nominal they are supposed to. Speed control on DC is attained by the controller varying the voltage to the motor. On DCC speed control is attained by the decoder varying the frequency of 12v pulses to the motor. Radio suppression capacitors can sometimes interfere with this. Brian Lambert has an illustrated guide to fitting decoders to the Ringfield motors found on older locos. http://www.brian-lambert.co.uk/DCC.html#The Link to comment Share on other sites More sharing options...
Fishmanoz Posted May 9, 2014 Share Posted May 9, 2014 Slight correction there poliss - DCC is PWM not FM, hence the width of the pulses, or their mark-space ratio, is varied, not their frequency. Link to comment Share on other sites More sharing options...
poliss Posted May 9, 2014 Share Posted May 9, 2014 I was trying to keep it simple. I can get all technicackle if you want me to? Link to comment Share on other sites More sharing options...
Fishmanoz Posted May 9, 2014 Share Posted May 9, 2014 Ok, ok, we don't want any cackling on here I don't think, we have enough shenanigans already. Link to comment Share on other sites More sharing options...
poliss Posted May 9, 2014 Share Posted May 9, 2014 If anyone wants the technicackle bits Mark Gurries explains them on his excellent website. PWM Motor Drive Waveforms: https://sites.google.com/site/markgurries/home/technical-discussions/decoder-motor-drive/pwm-motor-drive Problems Motor Capacitors can cause: https://sites.google.com/site/markgurries/home/technical-discussions/decoder-motor-drive/motor-capacitors Link to comment Share on other sites More sharing options...
jacksprat. Posted May 9, 2014 Author Share Posted May 9, 2014 Post a new reply... Link to comment Share on other sites More sharing options...
jacksprat. Posted May 9, 2014 Author Share Posted May 9, 2014 Hi Guys latest update on the loco, I have done as suggested and stripped down the motor could not believe how much s!!t there was on the commutator and brushes someone had been very liberal with the oil can. I think the motor could do with a new set of brushes but where do we purchase those from. I have had the loco running again although it was reluctant to start this time speed has improved or it did for a short time in forward direction only reverse direction was very poor (slow speed and stop start almost like a connection making and breaking under vibration tries the loco back in to forward and it is now doing the same thing stop start and the speed has dropped of again , could it be the brushes I cannot see any connection that is not connected properly. Just to give all of you professional people a laugh Ive just burnt out a DC ringfield motor on the DCC track left it stood for a while and couldnt understand where the smell was coming from till I so the smoke I thought it was only steamers that smoked?? I look forward to your replies its like I have made a whole bunch of new friends for which I thank you all Link to comment Share on other sites More sharing options...
Graskie Posted May 9, 2014 Share Posted May 9, 2014 I used to use a pin or, preferably perhaps, a sharper pointed needle. Link to comment Share on other sites More sharing options...
jacksprat. Posted May 9, 2014 Author Share Posted May 9, 2014 Do you not think new brushes as well? Link to comment Share on other sites More sharing options...
poliss Posted May 9, 2014 Share Posted May 9, 2014 If it's been oiled the brushes will probably have gone soft and need replacing. If it's a 3 pole motor you can buy a 5 pole upgrade version. It must be the 3 to 5 pole upgrade version. A standard 5 pole armature won't fit. Link to comment Share on other sites More sharing options...
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