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Hi,

I've got a Lenz Silver fitted into a Hornby 121, and it ran fine on DCC. I've had it running at 1/3 speed on DC loop for about 2 hours to run it in as the loop was running DC at the time.

It was fine to start, but now the loco will not go straight to full power on DC? It starts off slowly and builds up to max speed over three loops of the track. It didn't do that before! I did leave the loco for that two hours, and when I got back it had stopped. It needed more power to run again (slowly). When the decoder is removed, the loco is fast and totally normal.

When I fitted the decoder I fitted the Hornby heat shrink to the Lenz, but now read it should not have any??

Have I buggered my lenz decoder?

It still works on DCC, but some how it does not seem as smooth, seems just a touch jerky when underway??

Thanks

Rob.
 

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I need a bit more information.

1. Did you run the engine on DC with the decoder in ? (not a good thing to do). Always run the engine on DC for an hour each way, before fitting a decoder.

2. What sort of controller do you have, can it read CV's ?

You are right about the Lenz, I do not use covers.

If you can read CV's, check the CV numbers against the list in the booklet to see if they concur.

At the last resort, you can try resetting the decoder by programming CV8 with the value 33.

If you have damaged the decoder, the retailer should replace it free of charge as Lenz have an 'idiot' clause in their warranty.

I returned five during my first 6 months of DCC operation - so you are not alone.

Hope this helps

AlanB
 

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I would tend to reset the decoder, double check that the loco is 100% on DC & as Alan says remove the heatshrink from around the decoder.

The loco DCC should run fine on DC, but the acceleration delay (CV3) will actually still operate on DC. The maximum speed (CV5) willalso operate on DC.
 

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Discussion Starter · #4 ·
Hi,

Yes, the decoder was in for that DC run.

I'm using the NCE Power Cab.

I've reset the CV8 to 33, still runs a little lumpy at speed step 8. It didn't do that befoe. I think I will go back to the shop with my NCE, test track and loco. See if a new decoder is exactly the same. If it's not, I've damaged the decoder and I should get a new one?

Rob.
 

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QUOTE (alanb @ 15 Feb 2009, 09:57) <{POST_SNAPBACK}>.. If you have damaged the decoder, the retailer should replace it free of charge as Lenz have an 'idiot' clause in their warranty.
..
The warranty specifically excludes user modifications, unless pre-approved by application to Lenz: since the Lenz handbook says that no tape should be applied to the decoder, the retailer may consider the warranty voided.
 

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*** There is absolutely no negative on running a chipped loco on DC - the opposite ie: running a non chipped loco on DCC is the one to avoid.

The ONLY Brand that ever recommended against it was Hornby, as the early versions of their decoders were simply not able to cope with it reliably as they were well off spec. Current versions are I understand, better.

DC running is part of the NMRA specification for a decoder and is specifically catered for - in fact some loco's run better on DC with a decoder in than they did prior to chipping. This is to a degree dependent on chip choice of course.

Re the heatshrink on the decoder... it really should not be a problem but Lenz habitually use minimum spec parts so they already run hot. Lenz has a thermal protection in it so damage should not really have happened - however that does depend on track voltage and DC controller waveform - if your controller has a pulsed power then its possible it has been confused by it at best or at worst if you are very unlucky it may be damaged - a full reset will tell the story.

Richard
 

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Hi
Firstly ensure your dc controller is not a feedback type as this is not recommended with DCC fitted locos.
Even the Hornby HM2000 dc controller I understand (Though I don't own one, so I'm not 100% sure!) has some form of feedback fitted.
Also if you have any, turn off or disconnect any high frequency track cleaners such as the Relco units on the dc layout.
Both feedback controllers and Relco's can confuse decoders and possibly Relco's may damage them terminally.
Most non factory encapsulated decoder manufactures recommend a free flow of air over their decoder circuit boards, so don't use the heat shrink tubing.
Fix the decoder, if possible, in place by using double sided sticky pads (Lenz supply these - or they use too) If a metal chassis is in the fixing area, cover the area of exposed metal with PVC insulating tape before fixing the decoder in place.
 

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There were no track cleaners fitted and the controller used was a Gaugemaster 'Q' no feedback. The decoder can be fitted with just the sticky pad as it is fixed within a totally plastic body.

Rob.
 
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