2884 / 38xx Class 2-8-0 Steam Locomotive - Running it in

[N Quay Harbour]

Today I received the latest addition to my rolling stock, which arrived safely, as far as I can tell.

I haven't put it on my track yet because I read the IMPORTANT INSTRUCTIONS paperwork, quote: "Always run this model in on DC first before fitting a Dapol Approved decoder and running on DCC"

Would it be reasonable to expect that it has been run in if I am buying a DCC Fitted loco? Otherwise I have to take the decoder out, run it in with DC, then replace the decoder before I use it under DCC?

My current test layout is an oval with 5 sections that are connected to my Digikeijs DR5000 via a YaMoRC YD6016LN Current Sensor unit - i.e. DCC. Although I have a DC controller (a H&M Duette - which may not be suitable for N Gauge) it would involve quite a bit of rewiring in order to enable me to switch between DC and DCC. However, if I have to expect any new locomotive models to require running in under DC it is something I would clearly need to do.

Why can't I run it in under DCC?
 
Can you advise me please? Am I being too careful or not?

Thanks for your help

[PLD]

If it has a factory fitted decoder you don't need to remove it nor run in on DC first.
It is primarily aimed at users intending to fit their own choice of decoder themselves for two reasons:
1. If it doesn't run on DC, it's not going to work on DCC, so don't waste time fitting a chip...
2. If it runs Ok on DC, but not after fitting the decoder, it narrows down the potential issues to either a faulty chip or something you did while fitting it...

[JanW]

It is primarily aimed at users intending to fit their own choice of decoder themselves for two reasons:
1. If it doesn't run on DC, it's not going to work on DCC, so don't waste time fitting a chip...
2. If it runs Ok on DC, but not after fitting the decoder, it narrows down the potential issues to either a faulty chip or something you did while fitting it...

I don't think this is the reason for the advice to run a loco in on DC, I'm rather convinced the reason is the feedback in the decoder.
When running in the load on the motor should be light.
If a mechanism has a tight spot you'll notice it immediately on DC.
And even if you let it run in to loosen the tight spot the power to the motor will not increase but it simply slows down a bit on the tight spot.
On DCC the feedback will increase power to the motor to keep it running on the same speed. Load on the motor will be higher then.

I never run a loco in on DC but I listen carefully to make sure it runs smoothly on low speed and then let it run in on DCC.

Jan

[ntpntpntp]

Running in on DC is traditionally for the reasons @PLD mentions, ie. ensure the mechanism itself is fit for purpose and loosened up,  and it also stems from the days of hard-wiring decoders where it was strongly advised to test on DC first and turn up the voltage gently just in case of any short circuits or other mis-wiring faults.

With factory-fitted DCC I certainly wouldn't expect the loco to have been through any running-in, just a cursory power-up and check if you're lucky

As @JanW says, when running on DCC any feedback/load compensation enabled in the decoder could potentially disguise mechanical problems to some extent, and that still applies even when the DCC fitted loco is powered from DC.

I would still run-in on DC if you can just to do the gentle power-up (I did encounter a DCC fitted loco with a short due to excess/loose solder on the circuit board), but if you don't have a DC power source available then you have no choice but to run-in on DCC.

My test oval for servicing etc. is usually just some Unitrack and controller plonked on a table.