Running chipped loco on DC

[spikey]

If I were to buy a secondhand DCC-fitted loco, would I be able to run it on my DC layout straight out of the box?  And if so, would its performance change in any way if I removed the chip (and inserted a blanking plug if that's what's required)?

[Hamburger]

11 minutes ago, spikey said:

If I were to buy a secondhand DCC-fitted loco, would I be able to run it on my DC layout straight out of the box?

Depends on decoder type and mostly on decoder settings.

Eventually you have to change some CVs to activate DC mode and to adjust running charactristics.

 

11 minutes ago, spikey said:

And if so, would its performance change in any way if I removed the chip (and inserted a blanking plug if that's what's required)?

With a blanking plug it will behave as a normal DC loco.

[Pete the Elaner]

Some older decoders work poorly on DC. Since you are asking this question in the first place, I doubt you know what decoder is fitted.

 

Assuming the loco has a decoder which works ok on DC:-

 

DC running is enabled by default on most decoders, but the seller could have disabled it & forgot to reset the decoder.

Assuming it is enabled, it should run on DC fine. It may have a higher starting voltage than an ordinary DC loco, but this may be an advantage because the higher voltage will be able to bypass small pieces of dirt more easily.

 

Feedback controllers can damage decoders.

 

[WIMorrison]

Get the seller to enable DC Running in CV29 as a condition of the sale then you shouldn’t have any issues

[spikey]

Thank you, gentlemen.  I'm not going to know which chip the loco has in it, so if it doesn't work upon receipt, in practice I'd need to fit a blanking plug.  Am I right in assuming that if it doesn't come with any instructions that tell me what manner of blanking plug is required, I simply hit the internets with loco make and model number?

[cessna152towser]

I bought a new Bachmann DCC D11 a few years ago because it was on special offer from Hattons and cheaper than the DC version.   I never fitted the DCC chip but used the blanking plug instead.   The local was always difficult to control on DC - took a lot of power to get it moving, then it would pull away very quickly, so I re-sold it after a few months.

[Dungrange]

27 minutes ago, spikey said:

Thank you, gentlemen.  I'm not going to know which chip the loco has in it, so if it doesn't work upon receipt, in practice I'd need to fit a blanking plug.  Am I right in assuming that if it doesn't come with any instructions that tell me what manner of blanking plug is required, I simply hit the internet with loco make and model number?

 

I guess there is always the risk that the decoder has been hardwired into the locomotive by its owner, in which case you'll need to do more than just fit a blanking plate.  However, if it is a modern DCC ready locomotive that has had a decoder fitted by its owner into a pre-installed socket, then yes, you just need a planking plate for the correct interface, whether that is 8-pin or 21-pin format.

[Ron Ron Ron]

6 hours ago, spikey said:

If I were to buy a secondhand DCC-fitted loco, would I be able to run it on my DC layout straight out of the box?  ..........

 

Are you using a Relco or Gaugemaster, so-called track cleaner on your DC layout?

 

If so, you will need to remove the decoder from the loco as these devices will destroy the decoder and your loco won't run anyway, until you fit a blanking plug.

 

If you don't have one of these devices fitted, you should be OK to run the loco on your layout with the decoder left in situ...subject to the provisos mentioned by others above.

 

 

 

.

[Right Away]

As your railway is DC, unless you envisage going to DCC in the near future I would be inclined to remove the decoder and fit a blanking plug.

If you're determined never to go down the digital route, then it might be prudent to remove the DCC socket, rejoin the pick-up to motor connections which would alleviate potential (no pun) bad connections in this area.

[Phil S]

Also: if you use 'old-style' 'workhorse' pre (integrated) electronics controllers such as an H&M duette or clipper or Triang or Hornby Dublo speed controller .... Including probably any with a wirewound rheostat ....DON'T USE them for ANY DCC fitted loco, as the loco will not run properly and the decoder mightgoup in smoke !...,   Early pulse-width controllers were often mains-frequency based and effec tively switch off 100× a second.

 

Because..

These types of controller simply rectified the transformer output of the sinusoidal aç mains input ....so producing a 100Hz ( cyçles per second) fullwave rectified sine wave ( or worse .... Half wave rectified if the switch is so set ) .... This is UNREGULATED and can  easily peak at 28V on a '12Vdc' labelled output !!!!!   The voltage also falls to zero 100×  a second .... Causing the decoder's processor to keep restarting or get confused.

Decoders rated for only 16Vdcc are quite likely to go up in smoke due to the over voltage peaks.

( worse when no trains are running, as the unregulated voltage from the transformer will be at its highest when no or minimal current is being taken.)

A DCC fitted loço might for example, only run in one direction when used with such a controller.

 

However - on the positive side - if you have a modern, regulated / smoothed ( or high frequency pulse rate controller as with some gaugemaster models ( an example from experience ...the high frequency is effectively smoothed out ) then the loco should run well ...but its linear speed range from 0 to Max will start from a bit further round on the çontrol knob ....because the first process is to turn the processor on.  This may require 7V butusulally less with modern decoders.

[spikey]

No "track cleaner" gizmo here and I use a Morley Vector Zero Two, so I reckon I'm sorted.  Thank you, gentlemen.

[AMJ]

Depending upon the settings with the DCC chip you might find that it runs smoother with it in (assuming DC is enabled) on DC than with a blanking plug.  When I was chipping the layout I kept the shed and goods yard on DC and the main on DCC so that I could run items as and when I got around to chipping them.  Most DCC enabled stock would run with the acceleration rate as set in the chip.  Proviso as mentioned above by others.

 

Blanking plugs available from most local model shops or have a chat with a DCC friend as they'll have some assuming the loco is not supplied with blanking plug.  If taking it out you might be able to sell the chip.

[spikey]

Just to see what the party line would be, I rang Hattons this morning and said I'm on DC but I'm interested in a secondhand loco that's DCC-fitted, will it run OK for me to test it?  The helpful chap on the other end said "We don't recommend it", and when I asked why, he explained that "it could burn out the motor"!   So it would seem, at least as far as Hattons are concerned, that those of us running DC layouts should avoid buying DCC-fitted locos from them ...

 

Edited July 19, 2019 by spikey
Clarity

[Dunsignalling]

1 hour ago, spikey said:

Just to see what the party line would be, I rang Hattons this morning and said I'm on DC but I'm interested in a secondhand loco that's DCC-fitted, will it run OK for me to test it?  The helpful chap on the other end said "We don't recommend it", and when I asked why, he explained that "it could burn out the motor"!   So it would seem, at least as far as Hattons are concerned, that those of us running DC layouts should avoid buying DCC-fitted locos from them ...

 

I suspect they are covering their backs. The decoder is the vulnerable item, not the motor.

 

You haven't mentioned what the loco is, which might have made it easier to advise you, but what you really need to know is:

 

[1] Is it a loco that was factory fitted with DCC or "DCC ready" i.e. with a socket enabling it to be chipped easily by any Tom,  Dick or Harry. If the former, it should run OK on DC (unless somebody has disabled the function) If it has a factory-fitted socket but has had a chip added afterwards, things are less clear-cut.

 

If you can't find anyone to test run it on DCC, the easy/safe/foolproof course, in either case is to just remove the chip and insert a blanking plate.  Note that there is a right-way-round (marked). If it doesn't run, it won't be anything you've done and you can send the loco back with a clear conscience (don't forget to put the chip back in first).

 

[2] If the answer to question 1 is "no", you won't know what you are dealing with until you take the body off. Best plan (again) is to find somebody who uses DCC to test-run it for you, ensuring that CV29 is enabled. If it's OK, then it's your choice whether you run it chipped or convert it back to being a straight DC loco.

 

Once you are satisfied you have a runner, if you wish to de-chip a loco that's been hard wired, it's not difficult. There will be two wires connecting the motor to the chip, and two more connecting the chip to the pickups. Any others won't be doing anything unless the loco has working lights. Just remove the chip and connect the two pairs to one another. If the loco then runs the opposite way to all your others, swap them over.  

 

John

 

 

Edited July 19, 2019 by Dunsignalling

[spikey]

Thanks John.  It was a Hornby K1, but as it happens I've managed to find a new one (unchipped!) at a very good price.  I'm glad I now understand a lot more about chipped locos than I did, but I still wouldn't buy a chipped secondhand one.  To my way of thinking, the potential for damage, alleged damage or argument in the event that I wanted to reject the model is too great.  I'm happier waiting for a chipless version to come along, or simply going off the idea and moving to the next one down on my "I really fancy one of those" list.

[DCB]

On 18/07/2019 at 09:37, spikey said:

No "track cleaner" gizmo here and I use a Morley Vector Zero Two, so I reckon I'm sorted.  Thank you, gentlemen.

  The Morley gives a progressive increase in voltage so if the DCC chip needs 7 volts that will be around 1/2 way round the control knob from zero to maximum so no low speed control  or low speed capability.

We recently bought a  Morley Vector Zero Two and had some issues with poor running on the outside branch with light locos like the 64XX until I added a Relco. 

[Crosland]

On 19/07/2019 at 17:22, spikey said:

Just to see what the party line would be, I rang Hattons this morning and said I'm on DC but I'm interested in a secondhand loco that's DCC-fitted, will it run OK for me to test it?  The helpful chap on the other end said "We don't recommend it", and when I asked why, he explained that "it could burn out the motor"!   So it would seem, at least as far as Hattons are concerned, that those of us running DC layouts should avoid buying DCC-fitted locos from them ...

 

 

From that response he is obviously confused and thinks you want to run a DC (unchipped) loco on a DCC layout, which is not recommended.

 

So long as the voltage is within the limits of the decoder at all times then running on DC will not cause any harm. Pulse or feedback controllers may confuse a decoder and cause erratic running but are unlikely to cause any real damage.

[RAF96]

I have always found Hattons to be very helpful but not terribly accurate at times.

 

They have blamed some problems on Hornby kit, especially their own brand decoders, e.g. 

 

https://www.hattons.co.uk/68479/hattons_originals_dcr_8pin_direct_8_pin_compact_direct_4_function_1_1amp_decoder_with_back_emf/stockdetail.aspx

[Grovenor]

On 19/07/2019 at 19:36, DavidCBroad said:

  The Morley gives a progressive increase in voltage so if the DCC chip needs 7 volts that will be around 1/2 way round the control knob from zero to maximum so no low speed control  or low speed capability.

The DCC chip should give the full range of speeds, starting from very slow, when the supplied voltage varies from approx 7 up to approx 14, the quality of low speed control is a function of the chip here, not the DC controller.

Rgds

[DCB]

2 hours ago, Grovenor said:

The DCC chip should give the full range of speeds, starting from very slow, when the supplied voltage varies from approx 7 up to approx 14, the quality of low speed control is a function of the chip here, not the DC controller.

Rgds

Surely you will still need "Half throttle" to get 7 volts to initiate the crawl and that only leaves about 70 degrees from crawl to flat out. The  Morley pot is centre "off" so only does around 140 degrees from stop to flat out and 140 degrees the other way for reverse. There is no actual "Off" position as it goes straight from forward to reverse and finding a 0 volt position is effectively impossible.