Help with LGB mallett- conversion to DCC

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Roger the Dodger

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Hi
My name is Roger and I'm very new to all this. I've acquired an LGB mallett 2085D. It's a 3 wire gearbox, early type. I've added a fourth wire to each gearbox and isolated pickups from motor terminals, no issues there. In the smoke box is a pc board with 5 wires attached and a three position switch, marked 0,1,2 positions.
I'm converting the loco to DCC using an LGB 55020 decoder and 55030 motor booster. I'm thinking to hardwire the front rear and cab lights but am unsure about the smoke unit. Please can anybody tell me if the switch is for the smoke unit and if so could be discarded.
Alternatively if you could point me to a help guide on here I'd be very grateful. Many thanks.
 
Gizzy

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The LGB decoders you are fitting are quite old equipment now?

Might be worth considering a Massoth L decoder or an LS sound decoder.

Anyhow, although this is a later version of your loco, this might be of help....

 
Ralphmp

Ralphmp

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Hello Roger

The instruction leaflet for the 2085D 0-1-2 switch indicates that 0 is everything off, 1 is light and smoke unit but loco will not run, 2 is power, smoke unit and lights.

Fully agree with Gizzy's comment on decoders - I know from personal experience that a Massoth LS or XLS works well in the Mallet. However, if it's out of the question for now, it would be worth installing the LGB equipment so it can be readily swapped out should you decide at some future point to move to a more current model of decoder.

Best wishes
Phil
 
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Ralphmp

Ralphmp

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I've just found this link to instructions for early LGB locos including 2085D - it may help (Ignore title - it's a generic doc covering a range of models)

lgb-2080S-user-guide.pdf

Phil
 
Zerogee

Zerogee

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Hello Roger

The instruction leaflet for the 2085D 0-1-2 switch indicates that 0 is everything off, 1 is light and smoke unit but loco will not run, 2 is power, smoke unit and lights.

Fully agree with Gizzy's comment on decoders - I know from personal experience that a Massoth LS or XLS works well in the Mallet. However, if it's out of the question for now, it would be worth installing the LGB equipment so it can be readily swapped out should you decide at some future point to move to a more current model of decoder.

Best wishes
Phil
I don't know if it might have just been a typo, Phil, but I think that should have read an XL or XLS decoder? An LS is really only good for running a single motor, you'd be pushing its limits in a 2-motor Mallet.

I would also second (third?) the suggestion of not using the old 55020/55030 lashup - though I'm assuming you either have had them around for ages, or bought them very cheaply second-hand? The 55030 booster was VERY short-lived in LGB use, I've always assumed that was because it never worked very well.... and the 55020 is a very obsolete first-generation decoder with no back EMF facility.
I bought a factory-DCC Mallet from someone in Germany a few years back via eBay, and found it to be barely running - it had the 55020/55030 combo installed, and the 55030 had failed completely resulting in only one power unit running at all (and that one was out of quarter!) - the negotiated refund from the seller - as it had been described as fully working, of course - covered the cost of buying a Massoth XL to replace the very old factory installation; I did have a thread on here with pictures, but it seems to have disappeared for the moment (unless some nice person who's Forum-fu is strong today can find it where I failed?).

Jon.
 
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PhilP

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The 55020 also only supports 14 speed-steps. - I think you will have many problems with this as a first installation.
 
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Roger the Dodger

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I don't know if it might have just been a typo, Phil, but I think that should have read an XL or XLS decoder? An LS is really only good for running a single motor, you'd be pushing its limits in a 2-motor Mallet.

I would also second (third?) the suggestion of not using the old 55020/55030 lashup - though I'm assuming you either have had them around for ages, or bought them very cheaply second-hand? The 55030 booster was VERY short-lived in LGB use, I've always assumed that was because it never worked very well.... and the 55020 is a very obsolete first-generation decoder with no back EMF facility.
I bought a factory-DCC Mallet from someone in Germany a few years back via eBay, and found it to be barely running - it had the 55020/55030 combo installed, and the 55030 had failed completely resulting in only one power unit running at all (and that one was out of quarter!) - the negotiated refund from the seller - as it had been described as fully working, of course - covered the cost of buying a Massoth XL to replace the very old factory installation; I did have a thread on here with pictures, but it seems to have disappeared for the moment (unless some nice person who's Forum-fu is strong today can find it where I failed?).

Jon.
 
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Roger the Dodger

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Thanks everybody for replying. The only reason for using the LGB decoders was because I have them, however I also have a Massoth XL so will put that in. Obviously the switch can go as what it does will be controlled on DCC.
I have a further question though. Have read the Massoth instructions but it's not entirely clear to me -- what values do I need to change, and in what CVs to get 5 volts for lights and smoke unit. Planning to put loco lights on F0, cab light on F1 and smoke on F3
 
Zerogee

Zerogee

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Thanks everybody for replying. The only reason for using the LGB decoders was because I have them, however I also have a Massoth XL so will put that in. Obviously the switch can go as what it does will be controlled on DCC.
........
A very wise decision, and one that you won't regret making - the loco will run much better on the XL! Personally I would consign the 55030 module to the bin, and put the 55020 in the "bits box" in case you ever need a very basic decoder to run some lighting or other non-driving functions in something.
Just one question: your original post mentioned the Mallet being an "early type" 3-wire one, as borne out by its 4-digit model number - are you SURE that the lights are 5v? On a model of that vintage I would have thought they were more likely to be the old 18v screw-in bulbs rather than the more modern two-wire push-in type....? Is there anything that looks like a voltage stabiliser anywhere in the original factory wiring?

Jon.
 
PhilP

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If the lights are run at 5v.. They can always be made brighter. ;)

If 5v bulbs have 18-24v put through them, they maybe very bright initially, but then lack the capability to be made less-bright? :(


The XL will have front (and rear) light outputs, which you may wish to use?
CV 50 light dimming value
CV 53 A1&A2 dimming value
CV 112 A3&A4 dimming value

I would start with a value of '5' for the lights, and '6' for the smoke unit.

CV 54 (default '1') is the function key for the A1 output.
CV 113 (default '3') is the function key for the A3 output.

PhilP.
 
Zerogee

Zerogee

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Assuming you do actually have 5v bulbs (see my question a couple of posts above...), then please do note that the value entered into the dimming CV that Phil mentions is NOT actually a number of volts - each number in the CV value is (if I recall correctly) actually 1/32 of the total track voltage - so if you're running your DCC system at (say) 22v, each number of the CV value will represent 22 divided by 32 = about 0.69 volts; thus a value of 5 entered into CV50 will actually give you around 5 x 0.69 = 3.45v to the lights; to get closer to 5v supplied to the lights you would need a value of 7 in the CV, which would be 0.69 x 7 = 4.83v.

Sorry if that seems to over-complicate things.... don't worry too much about the numbers, the bulbs will happily tolerate a BIT of over-voltage as long as it doesn't go too high, so Phil's idea of starting at a CV value of 5 is a good suggestion to give a soft old-timey glow - if you find it's not enough, step the value up a number or two until you get them to the level of brightness that you want.

What DCC control system are you using? LGB MTS I, II or III, Massoth, Piko or something else?

Jon.
 
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Roger the Dodger

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Many thanks Philip and Jon. Most helpful and I'll start with a value of 5 and work up. I've tried the lights using a 5 volt transformer and they work fine, if a little dull. None of the bulbs are screw in type though.
I have an MTS system but I understand it will only do 14 speed steps. However I also have a Digitrax 5 amp system which I use for my 00 gauge layouts. Would this system be OK to program the Mallett with, as I'm very familiar with it? The guy whose railway these locos will run on has just bought a Marklin Central Station system so he will be able to run at 28 or 128 speed steps.
 
PhilP

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I use a Digitrax here for programming etc.
There can be slight 'inconsistencies' between Massoth and Digitrax, but nothing that should cause you untoward problems..

Just remember that a Marklin system will have a higher track-voltage than your Digitrax (19v for large-scale) so leave the bulbs a little dim, as they will be brighter on the Marklin system.
 
Ralphmp

Ralphmp

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I don't know if it might have just been a typo, Phil, but I think that should have read an XL or XLS decoder? An LS is really only good for running a single motor, you'd be pushing its limits in a 2-motor Mallet.

I would also second (third?) the suggestion of not using the old 55020/55030 lashup - though I'm assuming you either have had them around for ages, or bought them very cheaply second-hand? The 55030 booster was VERY short-lived in LGB use, I've always assumed that was because it never worked very well.... and the 55020 is a very obsolete first-generation decoder with no back EMF facility.
I bought a factory-DCC Mallet from someone in Germany a few years back via eBay, and found it to be barely running - it had the 55020/55030 combo installed, and the 55030 had failed completely resulting in only one power unit running at all (and that one was out of quarter!) - the negotiated refund from the seller - as it had been described as fully working, of course - covered the cost of buying a Massoth XL to replace the very old factory installation; I did have a thread on here with pictures, but it seems to have disappeared for the moment (unless some nice person who's Forum-fu is strong today can find it where I failed?).

Jon.
Yes, it was a typo - mea culpa! XL or XLS is the way to go IMHO
 
Ralphmp

Ralphmp

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Thanks everybody for replying. The only reason for using the LGB decoders was because I have them, however I also have a Massoth XL so will put that in. Obviously the switch can go as what it does will be controlled on DCC.
I have a further question though. Have read the Massoth instructions but it's not entirely clear to me -- what values do I need to change, and in what CVs to get 5 volts for lights and smoke unit. Planning to put loco lights on F0, cab light on F1 and smoke on F3
So, notwithstanding the excellent advice given above, I had an issue with light "dimness" on the first Mallet I added a decoder to. This appeared to have been caused by me being super cautious and setting the Massoth decoder to only push out 5v approx to the lights, but the loco already having a voltage stabiliser that ensured only 5V reached the lights. My assumption at the time was that by only pushing 5V into something expecting an input of 24V, the actual output to the lights ended up being less than 5V so they were very yellowy and dim. Increasing the Massoth decoder output back to full track voltage made the lights revert to the levels of dimness they had been at prior to the XLS installation.

I hope the above made sense.

Phil
 
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Roger the Dodger

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Thanks Phil. There may well be a voltage stabiliser on the old pc board, not sure what it looks like. However there are no Digital connections at all on the old board, it's very pre digital, lots of diodes etc so I aim to loose it completely and hardwire everything to the Massoth XL. Hoping to start the install tomorrow, fingers crossed.
 
dunnyrail

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Thanks Phil. There may well be a voltage stabiliser on the old pc board, not sure what it looks like. However there are no Digital connections at all on the old board, it's very pre digital, lots of diodes etc so I aim to loose it completely and hardwire everything to the Massoth XL. Hoping to start the install tomorrow, fingers crossed.
There are a few ways to go with converting LGB Locomotives to DCC/MTS. On an oldie like yours I think that I would be tempted to hard wire all the lighting back to the Decoder. Yes it makes more work but that old board is probably pretty well incompatible with what you are trying to achieve. You will be able with CV Values and using the correct pins on the Decoder get all of your lights working the correct way and using the right voltage for your bulbs. Just remember that by default Massoth Decoders shove out Track Voltage to all of the Lighting outputs so it is important to update them before shoving the Loco on a DCC Circuit. You would be able to do the updates in Program Mode without damage.

I am sure that some would say this is hereby, but I have done a few old LGB Locomotives in my time and adopted this approach with complete success. It is also the approach that I used to take with Piko Locomotives.

These days I am doing everything Battery Powered and do not bother with lights!
 
Ralphmp

Ralphmp

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There are a few ways to go with converting LGB Locomotives to DCC/MTS. On an oldie like yours I think that I would be tempted to hard wire all the lighting back to the Decoder. Yes it makes more work but that old board is probably pretty well incompatible with what you are trying to achieve. You will be able with CV Values and using the correct pins on the Decoder get all of your lights working the correct way and using the right voltage for your bulbs. Just remember that by default Massoth Decoders shove out Track Voltage to all of the Lighting outputs so it is important to update them before shoving the Loco on a DCC Circuit. You would be able to do the updates in Program Mode without damage.

I am sure that some would say this is hereby, but I have done a few old LGB Locomotives in my time and adopted this approach with complete success. It is also the approach that I used to take with Piko Locomotives.

These days I am doing everything Battery Powered and do not bother with lights!
Excellent advice, Jon. I've adopted a similar strategy myself unless the loco's factory-fitted sounds were something I wanted to preserve - e.g my Blue Mallet which has a whistle tone not available with any Massoth sound file I've heard.

Phil
 
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Roger the Dodger

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Thanks everybody, you've all been very helpful. Wonderful video Dunnyrail!