LGB 55025 - Digging Deeper & Help Question

[curtis]

I made a purchase recently on ebay for x3 LGB 55025 Point Decoders and had mixed results with what I received.

The first works fine. It was labeled with the address range and worked with both my hand controller and using the software on my PC (I was using MD Electronics Terminal + MD Electonrics MZSpro based on the Z21 system)

The second, didn't respond to the address listed and I couldn't read/write using the MD Software. However, I was able to write to CV1 using my Roco Controller and now responds fine.

The third, I can't read or write either from the MD software nor from the controller. It may be simply dead but I wanted to ask if anyone had any thoughts.

I opened up all 3 and although they're labelled as 55025 - the insides look quite different. The frst is sealed with a blue solid gel. The second two have visible circuit boards which appear visually different (components generally look the same but in different places) so I'm assuming slightly different.

So, on to my questions:
1. I understand there are different modes when interfacing with a decoder - could this be the reason I was able to set the CV with my controller but not with the software? Any recommended reading to get a better understanding (I found this but not sure if I'm on the right track)
2. Any thoughts/ideas on how to confirm if 3 is in fact dead?
3. Any other software recommended for attempting to programme 3?

Side note, for all of the above.

• No other devices connected to the track
• Load on section A (EPL switch)
• Prog terminals bridge

 

[phils2um]

Hi Curtis,
It's been awhile since I programmed my LGB 55025 switch decoders. I used the Massoth PC programming module to do it. If I remember correctly there is a Massoth Service Tool template for 55025. I've got another "new" unused one I can experiment with to check which CVs are used and what their values are. I'll let you know what I find out. The decoders I have are of MLGB vintage, nothing from the original Lehmann era . I opened the spare I have - the circuit board is potted with a black compound with a small MLGB part no. sticker on it. (What I think you call "solid gel" in your blue example.)

 

[muns]

Have you looked at this thread that I created years ago?

LGB 55025 Switch Decoder CV settings

Having been asked on another thread about CV settings for the LGB 55025 switch decoder, I thought it best to post my answer here in a new thread for easy reference: The LGB55025 switch decoder allows you to control 4 seporate point motors using independant accessory addreses. It is possible...

www.gscalecentral.net

 

[Greg Elmassian]

Wow! Could I have permission to put that on my site, of course with credit to you? That is fantastic, and have never seen that detail before.

Greg

 

[curtis]

Hi Curtis,
It's been awhile since I programmed my LGB 55025 switch decoders. I used the Massoth PC programming module to do it. If I remember correctly there is a Massoth Service Tool template for 55025. I've got another "new" unused one I can experiment with to check which CVs are used and what their values are. I'll let you know what I find out. The decoders I have are of MLGB vintage, nothing from the original Lehmann era . I opened the spare I have - the circuit board is potted with a black compound with a small MLGB part no. sticker on it. (What I think you call "solid gel" in your blue example.)

Yes, it sounds similar to what I have for the one that worked straight away.

I looked at getting the Massoth Service Tool but it seems they no longer offer it as a free download anymore. I'm in the process of trying to get JMRI working with my setup as I suspect there is some difference between how my controller and software are trying to update CVs

Have you looked at this thread that I created years ago?

LGB 55025 Switch Decoder CV settings

Having been asked on another thread about CV settings for the LGB 55025 switch decoder, I thought it best to post my answer here in a new thread for easy reference: The LGB55025 switch decoder allows you to control 4 seporate point motors using independant accessory addreses. It is possible...

www.gscalecentral.net

I did - it was an absolute goldmine. Thank you for creating it.

From your thread:

this could be the programming track of your central station, the LGB programming module (55045) or the LGB universal handset (55015) with the programming insert.

I only have the option of connecting via the track. My issue was that the second 2 weren't read/writable from the software (kept getting a decoder not found error). I managed to get one of them working by making the change via my controller. It seemed not to be a problem with the CV values themselves but the ability to read/write them. #3, I can't get a response from at all (controller or software), I believe it is completely dead.

 

[muns]

Wow! Could I have permission to put that on my site, of course with credit to you? That is fantastic, and have never seen that detail before.

Greg

Sure Greg, please do.

 

[phils2um]

I was playing with testing programming my spare 55025 using a Massoth PC programming module and Massoth Service Tool software this evening. There is a decoder template for the 55025 named "LGB_WEICHEN_001.xml" among the Massoth provided decoder templates. I set the decoder up for programming as per the instructions - programming terminals jumpered, a LGB EPL point motor connected to the "A" terminals, and the Massoth programming module track output connected to the decoder "IN" terminals. I used a Massoth 8135301 Switching Power Supply (19V, 4.7A) to power the programming module.

The Massoth template only shows 6 CVs as being programable. CV1 through CV5 and CV9. As explained in the info kindly provided by Mark in post 3, CV1 sets the address block, and CVs 2 through 5 configure the decoders 4 outputs. There is no description in the template as to what CV9 does, only that it can have values of 0 - 7. Perhaps this is a CV to perform a factory reset of the decoder? I will query the Märklin Digital guys about CV9. Or, maybe Mark knows what it does?

My Massoth programming module could "read" the 55025 CV settings for all six CVs in the template but returned meaningless values. If I tried reading the decoder it returned the value 7 for all the CVs 1 through 5 and a value of 0 was returned for CV9. It did not matter what values were actually programmed in the CVs. A CV read resulted in the same thing every time. I could write values to CVs 1-5 OK with the programming module. This was confirmed by writing various address blocks into CV1, then testing the decoder using my CS3 Central Station. The decoder and attached point motor responded to the expected address each time like they were supposed to. I did not try changing CV9 - I didn't want to inadvertently lock myself out!.

I also tried reading CV29 figuring it would come back with a value of 128 or more showing bit 7 was set for switch addressing. The programming module could not read anything. It returned an error message after failing three attempts to read CV29.

This is not very helpful to Curtis except the knowledge that he's not the only one having a problem reading 55025 decoder CVs. But maybe CV9 is the key to getting his third decoder functioning again?

 

[SevenOfDiamonds]

I looked at getting the Massoth Service Tool but it seems they no longer offer it as a free download anymore

Don't tell anyone I told you but scroll to the bottom of . . .

Massoth Service Tool – Massoth Elektronik GmbH

www.massoth.de

Cheers

David

 

[phils2um]

I heard back from Rick. This is what he had to say about CV9:

HI Phil, I'm not sure what CV 9 does. It probably doesn't do anything for a turnout motor. It is for the PWM of a locomotive motor in a locomotive decoder so it probably doesn't have a function in a turnout decoder and it might not be editable.

The "reset" of a decoder is CV8 and set it to a value of 8 to do the reset.




Rick Sinclair
Märklin Digital Consultant
650-569-1318



Curtis, you might try reseting the decoder you're having trouble with by writing 8 into CV8. I had forgotten this is common reset method for many decoders.