Must the Hornby non-motorised Mk3 DVT have a decoder fitted?

[Will Hay]

I have the mk3 Virgin DVT which lights up fine on my DCC layout with the blanking plate in place.

At the risk of appearing stupid, must I fit a decoder and if so, why does it add that I don't have already?

Thanks.

[Flashbang]

Hi

Hornby along with most other DCC manufacturers recommend that you DO NOT run a DC only loco on DCC power even if address 0 (Zero) is available. See the Hornby Elite and Select manuals re this.

Placing  a non-decoder fitted loco (DC Only) onto DCC powered rails will result in rather quick motor failure due to the motor windings overheating!

If you want to run the loco on DCC fit a suitable decoder and so long as DC operation has not been disabled it will then safely run on DC powered rails too.  😉

[Going Spare]

But would such a stricture apply to a non-motorised vehicle such as this DVT?

[Flashbang]

No, but the other end is motorised isn't it?  I assumed the OP meant the whole train? 

If just the unpowered end only, then my post above is not applicable.

Of course any lights fitted will not be able to be direction controlled nor can they be turned OFF without a decoder being fitted.

 

[Will Hay]

Hello everyone.

Hi again 'Going Spare'  😀

It's non-motorised, as the thread title.

I can't use a select or elite manual either I'm afraid, I use the Roco Z21.

 

Here's the funny thing, when I fit a [working] decoder to it the decoder doesn't register during programming, no lights, nothing.

Yet when I refit the blanking plate and place on the track the lights work fine.

 

Also, what directional lights are you referring to?

[Going Spare]

Directional lighting refers to white running lights illuminated when the DVT is leading the train and red tail lights when the DVT is at the rear of the train (i.e. the opposite of the lights showing on the class 91 loco).

[jane1707819582]

Hello everyone.

Hi again 'Going Spare'  😀

It's non-motorised, as the thread title.

I can't use a select or elite manual either I'm afraid, I use the Roco Z21.

 

Here's the funny thing, when I fit a [working] decoder to it the decoder doesn't register during programming, no lights, nothing.

Yet when I refit the blanking plate and place on the track the lights work fine.

 

Also, what directional lights are you referring to?

Place your DVT with the motorised loco on the track and programme the address together ( you can use the same address as the motorised loco ).Then using F0 the direction lights should work .you may have to alter the direction of the DVT so red lights when the motorised is white .

[Flashbang]

Yes Sorry,  I now appreciate what a DVT is.  In my book its Deep Vain Thrombosis!  Hope no one on here suffers these!  😆

Directional lights are the White headlights or white marker lights for forward movements and red rear lights on the back for forward moves. These swap around (or should!) when the train in going in reverse.  The red rears turn off and the white lights come on and at the former front end the white lights go off and the reds come on.

 

On DC these directional lights are rail polarity switched, but on DCC there is no such thing as polarity switching its all done by the on board decoder(s) using the Blue, White and Yellow wires on an 8 pin decoder.  

Also on DCC is that F0 (Function 0) turns On or Off directional lighting and on non sound decoders F1 can turn On/Off any additional lighting such as cab lights.(Cab lights may be not on your train but worth remembering).

 

I appreciate you may not have a Hornby Select or Elite etc but as this is the Hornby forum that is why I mentioned them.   

[Will Hay]

I ask of 'directional lights' because this only has lights on the front.

It's dreadful quality for circa. £65.00 BTW, dreadful.

I'll give that a try, Jane2, thanks.

So definately don't use this with a blanking plate, even if all appears well?

With no directional lights, the cost of the decoder seems a terrible waste and pushes a non-motorised, very poor quality loco near to three figures.

 

Thanks to all.

[Flashbang]

Hi

Just to be 100% clear...

On DCC powered rails you should always fit a decoder into any loco where there is a motor.  Failure to fit a decoder will result in very quick motor failure when the loco is run on DCC rail power.

 

Trailing unpowered carriages (No motor fitted) can be run on DCC without a decoder.  But any directional lighting (where fitted) will not work correctly.

 

If the loco and trailing carriage has directional lights, then the rear carriage will benefit from a decoder as this then will enable the lights to be switched On/Off and also of course provide full directional lights (Where fitted).  😆

[ColinB]

As the title of your post says it is "non motorised" so putting it on DCC is not going to do anything. Raw DCC will damage your motor as it behaves the same as AC. Basically because the motor doesn't turn the motor is in a pernament "stall" condition with no back EMF so it takes maximum current which will eventually burn it out. As a guide on new models if Hornby fit a DCC decoder socket then they expect you to fit a decoder, if it doesn't have one then they don't. If you do have to fit one what I do as it is only lights you are controlling fit a LaisDCC one at £10.00, you are not bothered how well it runs the motor.

[96RAF]

Whether or not you can program a non motored unit on its own depends upon your controller. The Elite for instance was updated a while back to be able to cater for programming of dummy cars fitted with decoders. Likely your Z21 manual will describe the programming methodolgy for dummy cars.

[Will Hay]

ColinB.

RAW DCC will damage my motor?

What motor?

This is essentially a coach with lights.

I'll take a look RAF96 but I'm happy, if it's safe, to simply have the lights on permanently by leaving the blanking plate in.

I have a much older Virgin dummy car on the back that has working [permanent] lights, no decoder socket and has never caused one ounce of problems.

[ColinB]

That is what I said, of coarse it won't damage your motor it doesn't have one. I was only stating the reason you mustn't put a DC loco on a DCC one. As I said "putting it on DCC is not going to do anything". The only thing you have to be careful about is if Hornby have wired up the lights to work on DC, then you might get the headlights on when you are going backwards.

[Will Hay]

So, I can leave the blanking plate in?

[ColinB]

Yes you can. I assume by blanking plate you mean the 8 pin DC header. If you want the lights to works properly you will need a decoder in the 8 pin socket, but if you are not bothered about the lights then yes leave the blanking plate in.

[Will Hay]

Righto, thanks.

[Will Hay]

I presume that what happened to the following, the exact same model, is completely un-related, being that it was used successfully for nine months before catastrophic failure.

 

https://www.hornby.com/uk-en/forum/post/view/topic

[Flashbang]

Hi

Unfortunately your link in the above post is incomplete and doesn't lead to any posts!

[96RAF]

... If you want the lights to works properly you will need a decoder in the 8 pin socket, but if you are not bothered about the lights then yes leave the blanking plate in.

 

Not exactly true.

Most blanking plugs link the track to motor and the directional lights, so a blanking plate will work fine. The manufacturer provides it for just such a purpose.

[ColinB]

Yes, you are absolutely right but they rely on diodes to do it, which is great on DC but on DCC they will probably switch the headlights on when you are going backwards, which is exactly what I said. Possibly they might flash on and off, I don't know. What I do know is that Hornby fitted that socket for a reason so they must think the same as me. This is effectively the same as a Pendolino or a Javelin, in both cases I have fitted a really cheap decoder to the dummy end which again is what I recommended.

[Will Hay]

Virgin DVT set on fire...

 

https://www.hornby.com/uk-en/forum/post/view/topic_id/33995/?p=1

[Flashbang]

If you remove the DC operation "Blanking plate" nothing at all will work, whether on DC or DCC! No lights or if its inside a loco, no motor controls.

The blanking plate plug allows a loco or unpowered carriage to work correctly on DC (Analogue) control.  Once its removed and its socket is left open there is no connection to anything!  

Replacing the blanking plug with a suitable decoder and on DCC power you can then adjust the decoder to allow lighting or motor (where a motor is fitted) operation to work at its best. 

[Flashbang]

As for the images of the burnt carriage, its impossible to say what caused this? But there are few possibilities...  Over heating decoder due to it having insufficient air flow - Its been wrapped in insulating tape or shrunk down heat shrink tubing.   The decoders components have over heated due a fault after the decoder.  The PCB of the carriage or loco has defective components or they have failed or have been subjected to an overload.  The decoder was installed incorrectly and a partial short circuit has become present allowing larger currents to flow causing overheating.  

 

But of course none of this will return the carriage or loco to its original condition.

But what should be learnt is that with DCC large currents can flow under fault conditions than ever seen with DC.   

Generally on DC the maximum current is around 1.0Amp on DCC this can be 4 or 5 Amps or more depending on the DCC system used. in the USA some DCC users will often have 10 Amp systems.   Consider this....Typical DC = 12 volts at 1.0 amp is equal to 12 watts.  On DCC 4 Amps at 15 volts is roughly 60watts, while 10Amps at 15 volts is 150Watts.  

60 watts is very hot.  Consider a conventional filament lamp rated at 60 watts. Its extremely hot! In fact don't touch such a lamp when lit, it will probably burn you!

[Will Hay]

Hello.

The burnt out carriage you're looking at was used exactly as this one will be.

No decoder fitted, never opened, blanking plate never removed.

 

Hornby have been very good, I have to say.

Replaced without question, including my return postage costs.