I blew up my DR5000 - any workarounds for not having LocoNet ports?

[Carl]

I'm in the middle of laying my fiddle yard, and have been testing each point I lay once I've installed the occupancy detection and point motor for it.

 

My setup is :

 

- DR5000, the "track" output is the feed for my accessory bus, for the whole layout.

- DR5033, connected to the DR5000 with LocoNet, and this (and two others when I get that far) provide track power in three districts.

 

This morning, whilst laying some track, I left the track power on after testing, and when I went to solder on of my bus wires either the DR5000 or DR5033 tripped (as you'd expect.)  I'm not 100% sure if it was the track or accessory bus now, but the upshot is that the next time I went to test, I had no track power.  After some diagnosis, it turns out that neither of the LocoNet ports on the DR5000 are outputting anything - so the fault is with the DR5000.

 

The DR5000's track output is still working, and I if I connect that to my DR5033's track sniffer input, it is working too.  So I can continue laying track and testing as I go.  I'll order a new DR5000, my luck is that everywhere seems to be out of stock.  I have also contacted Digikeijs about this.  So it seems like it's just LocoNet which is not functioning.

 

What I'm wondering is if there is some clever workaround for my DR4088LNs (which I use for occupancy detection) now not being able to communicate back to the DR5000, by utilising some other ports on the DR5000 or something.  Or whether someone else had done the same, and managed to repair the DR5000.  Grasping at straws, I know!

 

I do have a Loconet-XpressNet DR5099 Diginethub which had me excited for half a second, until I Googled that the XpressNet and LocoNet sides are completely separate ...

Edited February 19, 2021 by Carl

[sotars]

I did exactly the same thing last year.  I dropped the soldering iron on the track which was live and powered by a DR5033 booster and not from the track power on the DR5000. It took out the DR4088LN connected to that particular section. The DR5033 booster was untouched but the Loconet port the DR4088LN was connected to again was taken out. I contacted Digikeijs and they asked me to return it for diagnosis and repair. They did repair it but it took 6 weeks for them to return it completely repaired. Meanwhile I purchased another DR5000. The repaired DR5000 is sitting in the cupboard in case I drop the soldering iron again. 

 

Alex Thomson

[Carl]

Thanks, at least my diagnosis seems correct.  I don’t have a way of checking the DR4088LN for that section, but at least they are cheap compared to a DR5000!

 

I found someone with one in stock, so that’s on the way.  Hopefully Digikeijs can repair the DR5000 I have, if only to have a spare like you!

[Nigelcliffe]

It sounds like grounding the the system via the LocoNet connections.   Blowing up LocoNet ports due to inadequate ground connections is a fault seen on Digitrax forums for decades (those ones usually come down to not following the instructions about establishing a layout common ground, with adequately thick wire for that ground link).  

 

I note Digikeijs refer to some command stations where the ground is not the same as theirs (eg. Uhlenbrock), and offer opto-isolated devices for some circumstances.    

 

I speculate whether an opto-isolating parts of the LocoNet connections which cross booster power districts could prevent the issue happening in future.

 

 

- Nigel

[Edwin_m]

Pure conjecture but may be worth a try?

 

Loconet has separate wires for the power to operate the connected devices and the communication to and from them.  This problem sounds as if it might relate to the power side of the Loconet, and the communication could still be OK.  In which case an external power supply with the correct voltage and polarity might work.  

[Carl]

On 20/02/2021 at 10:08, Nigelcliffe said:

I speculate whether an opto-isolating parts of the LocoNet connections which cross booster power districts could prevent the issue happening in future.

 

That's really not a bad idea, if I can find an appropriate, cost-effective device.  I can't immediately find one, do you have any suggestions?

 

Digikeijs suggest that the DR5000 it is probably going to cost as much to fix as a new one is, since it's out of warranty, but will check for me if I send it to them.

 

If anyone does find this and wonder about Digikeijs' out-of-warranty repairs work, the first 10 minutes is free, then they charge €12.50 per 15 minutes to a maximum of €50, plus parts and shipping.  In this case they suspect it will go back to the processor.  I'll send it them though, worth the shipping to find out.

 

I found one in stock over the weekend, and have ordered a replacement anyway.

 

Edited February 22, 2021 by Carl

[Carl]

On 20/02/2021 at 12:50, Edwin_m said:

Loconet has separate wires for the power to operate the connected devices and the communication to and from them.  This problem sounds as if it might relate to the power side of the Loconet, and the communication could still be OK.  In which case an external power supply with the correct voltage and polarity might work.  

 

I attached my oscilloscope to the ports, and nothing unfortunately!  Thanks for the idea though, that would have done me for a few days.