Checking Pickups with DCC

[Isambard Kingdom Brunel]

I have a couple of DCC loco which are really indifferent runners on track, is there a way to check pickups in DCC.

Using DC I used to have two pieces of wire which I could touch to individual wheels to test.

I have read that DCC loco should work with DC, but mine dont seem to want to.

Any advice please?

Edited April 15 by Isambard Kingdom Brunel

[Nigelcliffe]

Just use the same wires with your DCC controller.   That should show up any issues.  

 

 

( Most decoders should support DC running, there are a handful that don't.   But its an end-user setting in CV29, so may have been turned off.   And they require a clean DC signal, some DC controllers are extremely noisy.  ).  

 

[WIMorrison]

You can check pickups on the bench using DCC in exactly the same way that you use DC - no difference, but you may want to make CV3 and CV = 0 before you start to ensure that the locos run without the extreme inertia characteristics that are often used.

 

I assume the second DCC statement means DC? In which case you need to read CV 29 and add 4 to the value that you read. You can check the setting by using this link. (if the value already in CV29 shows that DC running is already enabled then you would appear to have an issue.

 

DCC CV29 Calculator (2mm.org.uk)

[34theletterbetweenB&D]

13 minutes ago, Isambard Kingdom Brunel said:

I have a couple of DCC loco which are really indifferent runners on track, is there a way to check pickups in DCC

Use the programme track, it's more sensitive to poor pick up performance than running lines.

If like mine the programme track is a dead end piece of track, most locos can be poised with just one pair of wheels on the rails. If the system reads the address, those pick ups are ok.

[Isambard Kingdom Brunel]

44 minutes ago, WIMorrison said:

You can check pickups on the bench using DCC in exactly the same way that you use DC - no difference, but you may want to make CV3 and CV = 0 before you start to ensure that the locos run without the extreme inertia characteristics that are often used.

 

I assume the second DCC statement means DC? In which case you need to read CV 29 and add 4 to the value that you read. You can check the setting by using this link. (if the value already in CV29 shows that DC running is already enabled then you would appear to have an issue.

 

DCC CV29 Calculator (2mm.org.uk)

Thanks Iain, I have edited that to read DC

[GrumpyPenguin]

hmmmmmm - the problem with checking pickups on DCC is that if you have acceleration set it can take a while to react.

 

I use a straight forward multimeter set to resistance - locomotive on it's back (suitably protected) & try one side at a time - one probe on the first axel with pickup, the other probe on the next axel - if you have continuity then move the other probe to the third axel & so on.

Next, same again on the other side. Any lack of continuity with be a pointer to where the issue lies.

When checking move the axels sideways to see if the wipers loose contact as they would on curves/points.

[WIMorrison]

Just now, GrumpyPenguin said:

hmmmmmm - the problem with checking pickups on DCC is that if you have acceleration set it can take a while to react.

that is why I said in my earlier post to set CV3 and 4 to zero …

[WIMorrison]

3 minutes ago, GrumpyPenguin said:

When checking move the axels sideways to see if the wipers loose contact as they would on curves/points.

If your locos lose contact on curves or turnouts then you have a problem. The reason the contacts are springy is to allow for the side to side movement and you should never lose connectivity between the wheel and the contact.

[GrumpyPenguin]

4 hours ago, WIMorrison said:

that is why I said in my earlier post to set CV3 and 4 to zero …

& then you have to re-set them again, i find the way I test much quicker.

[GrumpyPenguin]

4 hours ago, WIMorrison said:

If your locos lose contact on curves or turnouts then you have a problem. The reason the contacts are springy is to allow for the side to side movement and you should never lose connectivity between the wheel and the contact.

Which is why I suggested moving the wheel assemblies from side to side.