.

[Dog Star]

I think I will order one for my 31 and see what happens, its getting a V4 loksound chip ...

I did not enjoy the experience of either removing some of the decoder protective sleeve or soldering the keep-alive wires to the sound decoder.

The instructions with the keep-alive are not clear and I rang SWD to resolve the uncertainty. The pads on the sound chip are very small and very close together... I gave up with trying to solder the wires to the pad and passed the entire shooting match to an electronics engineer who did the work as a Homer (Simpson). I recollect that the lady at SWD said that the wires can be attached before dispatch if the chip and keep-alive are ordered at the same time.

Otherwise... have a discussion with Brian Clapperton who does know how to attach the keep-alive to the 21-pin harness of a Loksound V4 - Brian has used elektrikery thingies to work out which pins on the plug are associated with the relevant pads of that sound decoder.

regards, Graham

 

[TheSnapper]

An added benefit, or a gotcha-to-be-aware-of, is that the keep alive does do just that... so the engine does "run on" about 12" more than without the device. I do not understand why this is... regards, Graham

I had the Lenz stay-alive system demonstrated to me a few years ago on an H0 German layout at Warley, albeit in a non-sound loco. It was removed from the track & carried on running for some distance along the baseboard. A bit OTT, I thought afterwards, especilly considering the additional cost.

My feeling is you just need enough stored power to counteract any slight loss of contact with the track (dirt, uneveness etc) and to keep the sound going without interruption.

Incidentally Richard, I have fitted a V4 in my Heljan Class20 with no problems (albeit with no lights/fans of course...!)

Tim

 

[Steph Dale]

I did not enjoy the experience of either removing some of the decoder protective sleeve or soldering the keep-alive wires to the sound decoder.

The instructions with the keep-alive are not clear and I rang SWD to resolve the uncertainty. The pads on the sound chip are very small and very close together... I gave up with trying to solder the wires to the pad and passed the entire shooting match to an electronics engineer who did the work as a Homer (Simpson). I recollect that the lady at SWD said that the wires can be attached before dispatch if the chip and keep-alive are ordered at the same time.

Otherwise... have a discussion with Brian Clapperton who does know how to attach the keep-alive to the 21-pin harness of a Loksound V4 - Brian has used elektrikery thingies to work out which pins on the plug are associated with the relevant pads of that sound decoder.

regards, Graham

Darn it - forgot that one. If you order the 21-pin version of the decoder and it's backplate you have nice big pads to solder the Power on to (on the backplate). As an aside, there's a version of the backplate that will also support an extra two functions, so turns the LokSoundv4 into a DCC+s 6-function decoder and the LokPilotv4 into a DCC 6-function decoder. A useful trick which, for some models, more than justifies the price of the backplate circuit!

(items 51967 and 51968 are the plain and 6-function 21MTC adaptor boards, respectively)

Steph

Edit - just been on to ESU's website to check the item numbers and noted that they're bringing out fan-assisted smoke units this year which will synchronise with either steam or diesel sounds. If this is anything like the system they packed into one of their German H0 diesels it'll really be something to look out for. So says he who doesn't 'do' smoke...

 

[Dog Star]

If you order the 21-pin version of the decoder and it's backplate you have nice big pads to solder the Power on to (on the backplate).

What do you know about the pin-out configuration for attaching the ESU keep-alive / power pack to the 21 pin harness plug/socket? I ask because SWD was not able to help with that information when I purchased the power pack module last September.

 

[Steph Dale]

Graham,

IIRC you have to cross reference the manuals for the 21-pin decoder and the backplate to work out which pads to solder on to. The complication is that when I last searched for it (some months ago) the manuals for the backplates weren't on the ESU website.

I'll have a look through my notes when I next get the chance, give me a couple of days...

Steph

 

[Dog Star]

... you have to cross reference the manuals for the 21-pin decoder and the backplate to work out which pads to solder on to.

Steph, the two part numbers that you have quoted in an earlier post are what I expected.

I think that we have used 51967 - I cannot check without dismantling the engine. Irrespective of which socket is the one that we bought, I do not recollect there being anything in the paperwork which could answer the question about pin allocations for the three ESU "Power Pack" supply connections. On the other hand, the LokSound instructions gave me pain in trying to understand how to synchronise the sound etc. so I may have just turned off at some point and gone for Earl Grey and Tiffin (one of the few known antidotes to "added nuisance value" ).

regards, Graham

 

[Steph Dale]

Hi Guys,

Are the Hejan's 'current hungry' remember those tests that Mike did for us - they didnt seem quite so hungry as we all first thought

ATVB

CME

Well, mine is - it'll happily trip my 'heavy duty' KPC analogue controller. Yep, that's the one with the 2A cut-out...

It's also fair to say that I'm not sure of Mike's method of testing so I'm not entirely sure what to make of his results; mine are a little different. However; one thing to consider is that DCC can have acceleration/deceleration programmed into the decoder which reduces the current demand. It's the hard acceleration/deceleration which is the issue. Asking those motors to accelerate a 3.5kg model and that pair of comedy flywheels is where the trouble comes in. The demand under those conditions will be much higher than with the loco spinning its wheels.

One thing I will be trying is to remove the flywheels (entirely pointless with DCC, and the ruddy things 'ring' like the bells they are) and wire the motors in series. My suspicion after recent testing with my Cl37 is that this will get me exactly where I want to be with regards to performance under DCC control and allow use of a standard (H0) decoder when suitably gentle acceleration/deceleration values are programmed in.

Steph

 

[Ressaldar]

It's also fair to say that I'm not sure of Mike's method of testing so I'm not entirely sure what to make of his results; mine are a little different. Steph

Hi Steph,

I used a Helmsman 5Amp controller fitted with both a volt meter and an amp meter and turned the power up gradually to the stated voltages in my report and read of the readings - very basic and no rocket science.

cheers

Mike

 

[Steph Dale]

Hi Steph,

I used a Helmsman 5Amp controller fitted with both a volt meter and an amp meter and turned the power up gradually to the stated voltages in my report and read of the readings - very basic and no rocket science.

cheers

Mike

Mike,

I concur with that; a sensible method. The risk is that we're not exploring 'realistic worst case' with regards to current draw. I'd agree that the very rapid acceleration I quoted above probably isn't realistic for DCC because of the acceleration/deceleration values in the decoder. But I would be interested to know how much current the locos draw if they were (for example) driven into a buffer stop; I suspect it'd be a good bit higher than the values you quoted.

Steph

 

[Ressaldar]

Mike, But I would be interested to know how much current the locos draw if they were (for example) driven into a buffer stop; I suspect it'd be a good bit higher than the values you quoted.Steph

Hi Steph,

unfortunately, there are no buffer stops on our continuous run but I'll try and rig something up over the next few days and come back to you.

cheers

Mike

 

[Simon Dunkley]

Instead of running the loco into the stop blocks, isn't the aim to find the stall current, i.e. trying to run the loco when pushing down on it, to stall things, and to find the current draw at that point. This would be the worst case scenario?

 

[Steph Dale]

Instead of running the loco into the stop blocks, isn't the aim to find the stall current, i.e. trying to run the loco when pushing down on it, to stall things, and to find the current draw at that point. This would be the worst case scenario?

Simon,

Well yes, It's certainly the worst case scenario (in fact, why not just clamp the wheels and test it then under true stall?), but it's not really a 'realistic worst-case' is it? I don't operate my locos while leaning on them, but they might (in error or under a fault condition) hit the buffer stops or end of the layout while accelerating. What will help is to get a grasp of this sort of current draw, rather than what's in essence a steady-state 12v figure from Mike's initial testing.

The truth is that although I've heard people advocate true stall testing (literally jamming the mechanism to determine the maximum amount of current the loco might pull) and rating a decoder above that level, I recognise that if that happens I might be grateful for the decoder to pack-up or at least self-protect. It's a bit of overkill for a scenario which (I hope!) will never be played out in reality. I'm just trying to find a pragmatic solution - Mike's values are probably too low for my needs (I have bufferstops and novice operators to worry about), but I don't consider a true stall to be a credible operational situation either. It'd also be good to determine if this pragmatic solution still allows use of H0-scale decoders rather than large-scale decoders in the Heljan models; there's a significant price advantage if that's the case.

Steph

 

[Osgood]

I would have thought that pushing down would give an unrealistic scenario, as the max load will be determined by wheel slip - increased of course if additional ballast is used.

Would not max. Load occur at max tractive effort which results in wheelslip on a heavy train which is effectively what the buffer stop test simulates?

 

[Steph Dale]

I would have thought that pushing down would give an unrealistic scenario, as the max load will be determined by wheel slip - increased of course if additional ballast is used.

Would not max. Load occur at max tractive effort which results in wheelslip on a heavy train which is effectively what the buffer stop test simulates?

Yep. You're right about the thought of additional ballast, I hadn't allowed for that. Although in Heljan locos I'm perhaps less sure; they're heavy to start with. And accelerating while at the buffer stop adds a little to what you've said as more current is required to accelerate (broadly/simplistically, I know!).

Steph

 

[Simon Dunkley]

Agreed - I was quoting standard practice, which is just silly. I would never weight a loco to the point where it could stall, as it should be able to lose its wheels and slip, so a simple clamp on one of the rails would do (or a nail/bolt in the 4'!), in the absence of stop blocks?

 

[Steph Dale]

Agreed - I was quoting standard practice, which is just silly. I would never weight a loco to the point where it could stall, as it should be able to lose its wheels and slip, so a simple clamp on one of the rails would do (or a nail/bolt in the 4'!), in the absence of stop blocks?

Simon,

Sure; my length of rubbish Peco track has a upward bend in one of the rails to form a 'stop' against one of the loco's buffers. It took a bit of doing, but gives me a simple stall test arrangement when I'm not at the layout.

Steph

 

[Osgood]

The point about stall current is a valid one - I guess if the gearing jammed up then the DCC devices attached would be subjected to the stall current.

But (remember I'm struggling up a very steep learning curve here) I would expect a quality power supply to have some kind of max output limiter - for example to limit the output of a 4amp controller when using smaller locomotives? Can't recall seeing any provision for this though.

In its simplest form each loco could be fitted with a fuse sized to protect the DCC chip, although there must be something more sophisticated out there!

 

[Steph Dale]

All (or at least most) decoders have in built self-protection which cuts the power of they get a temperature rise of over-current. The issue is that they can take a while to activate, so it's worth reading your decoders appropriately.

Your comment about jammed gears is one of those where I think I'd want the decoder to self-protect even burn out, rather than risk more serious damage to a model. Especially one with plastic gears, which is roughly where we came in, I think...

Steph

 

[Simon Dunkley]

In its simplest form each loco could be fitted with a fuse sized to protect the DCC chip, although there must be something more sophisticated out there!

HoG used to include a fuse with RG7s. It's not a bad idea, and certainly is a sophisticated enough solution. No need to over-complicate matters.

 

[Osgood]

HoG used to include a fuse with RG7s. It's not a bad idea, and certainly is a sophisticated enough solution. No need to over-complicate matters.

I'll certainly put a fuse on my 31 which I am currently hoarding on the shelf (like I'm going to admit to having that on the other thread......). Just waiting for the consensus on series / parallel, chips, speakers etc. No rush - I've only just got the railway room onto site!