Dcc power supply for an HM7000 decoder

[TugBoatTel]

Ok, so I'm sure this has been talked about before, but I can't see it.

I received the HM 7000 next 18 Decoder, a couple of days ago, and had hoped to fit it in the loco tonight, BUT it doesn't say what Supply voltage it requires. Looking at the power supply the transformer gives out 19volts to the controller.....Hmm, DCC is normally 15VAC, and as Sam (from Sam Trains) decoder went POP I don't really want to copy it.

I, will probably end up using my Ecos with it, but it be nice to use the Bluetooth.

I'm guessing it isn't mentioned deliberately, as they didn't want it set in stone.

Any one else got any advise please??

cheers

[Rallymatt]

This is more a HM DCC area query rather than specific to TT:120. Do you already have the Ecos DCC system?

[96RAF]

Sam used the raw output from a DC controller not DCC, which is a regulated waveform within NMRA specified voltage limits. He destroyed his decoder by not reading the instructions and using a non approved power source.

You can safely connect your ECOS to the track at the DCC voltage on the rails will power your Bluetooth decoder and allow it to be controlled from the app or as it comes out of the box on DCC by your ECOS.

The decoder manual clearly states the voltage limit is 27 volts but recommends 15 volts. Your transformer feeds 19 volts into the ECOS which conditions the voltage and waveform and puts 15 volts DCC to the track. The decoder, conditions this track voltage and provides 0-12 volts to the motor and 14 volts to accessory circuits.

[TugBoatTel]

Many thanks. First class answer. Hmmm I looked and looked but didn't see anything other than a list of transformer numbers. I do love my ecos, so I was going to go down that route, but just thought I'd check. Am in the process of moving, so may have missed it in the rush.

THANKS FOR THE HELP. I wonder if they will release a small sound card to fit in the 08. Hope so. Can still remember the last steam train (guy with the red flag going down the sea front) then in the wellington docks and seeing the black 08 starting up to manage the sidings.

Cheers

Happy days.

[TugBoatTel]

Yep RallyMat. Yes, have a much loved Ecos. Have my moving house head on, so it's in a box ready to go. As you say wrong topkick..oops

Got,an 08 coming tomorrow I hope. Will try to fit a small 6pin Lenz decoder and add some tyre weights where the flywheel would have gone. :)

[ColinB]

The decoder manual may state the voltage limit is 27 volts but there must be something wrong somewhere. I measured the unregulated output from my really old H & M duo when it blew up one of my Zimo modules I was running in DC, it was about 21 volts and if you think about it peak is 1.414 of rms, so 27 means an rms voltage of 19 volts. Now 19 volts would cook a loco on DC. I suppose you could get an inductive effect that might give above 27 volts but I am not so sure. I suspect the maximum voltage is actually between 18 and 20 volts, which seems to be the maximum a Zimo module seems to run at.

I don't know enough about their exact module design but that is just a calculated guess. Anyway Sam uses a modern HM supply to run his trains, so I doubt his controller will be throwing out the same sort of DC an old H & M one would, so not the same issues. When I studied my HM7000 a lot of those components looked extremely small, now sure they work, but being so small there is not much surface area to dissipate heat. So if something goes wrong these devices fail. In fact the decoder manual also has a very high motor current limit which also looks a bit optimistic. Seeing as this was a very rushed design, highlighted by the Android app not working, I would be very dubious of a lot of the figures stated.

[Fishmanoz]

Colin, would you care to explain to the readers, particularly the OP, what relevance there is to a treatise on DC supplies, including quoting peak v RMS voltages on non-sinusoidal waveforms, has to do with powering HM7000 from track DCC?

[Rallymatt]

TBT glad you got this into the right section of the forum and Rob (96RAF) has given you the info you needed. As a rule of thumb, if you have an existing DCC system, you have no power issues. Switch between App/DCC control as you like. I use my DCC system for day to day running but do all the changes and obviously sound uploads via the App, it’s so user friendly 😁

[96RAF]

@fishy

Colin cannot reply due to his defamatory remarks on another post generating a complaint direct to Hornby Towers, resulting in the mods being instructed to put him in the sin-bin for now.

Ref his remarks above. . .

Quote - Seeing as this was a very rushed design, highlighted by the Android app not working, I would be very dubious of a lot of the figures stated.

The design was not rushed, it has been in the system for more than 2 years, and the Android app does work but did not enter testing until recently. The figures stated in the decoder manual are accurate. The damage is done not by high steady voltage but wild spiking which can be well over design limits for the decoder.

I agree some of the decoder components are like specs of dust but they are rated to handle the design loads. You cannot have a tiny decoder with big components, so they are the size they are to do their job within availability of parts on a certain date when the design is sealed for production.

[Carbone]

This is a truely weird forum. It is Stalinistic in the control by the moderators. No dissent is tolerated and posts are deleted if they don't agree with the opinions of moderators.

No wonder it is so quiet and only the same few people post.

[SteveM6]

Could I politely suggest a re-reading of the forum rules.

I can see at at least two rules that were not adhered to, plus as was said earlier, a direct complaint was made to Hornby regarding comments that had been made that challenge the integrity of both Hornby and the person that the comments related to.

I am not a moderator for this forum but can I also suggest that comments are confined to the original subject of the thread.

[Carbone]

QED.

P.S. How do you complain direct to Hornby Towers? i can't find the link anywhere or is it just for the privileged few?

[Fishmanoz]

Click the 3 dots on a post that concerns you and one option is Report.

[96RAF]

P.S. How do you complain direct to Hornby Towers? i can't find the link anywhere or is it just for the privileged few?

 

 

In defiance of the rules not to give feedback on such matters ...

This type of anti-moderator discussion raises its head again and again over the years with the same outcome, those complaining generally lose interest and we hardly ever see them again. Stereotypically they have added little of use in their time on the forum.

If you had read my reply properly you would see that the moderators were instructed by Hornby to take action. It was not a Stalinist ego trip.

In addition to the report facility Fishy pointed to, anyone can write to or phone Hornby using the Contact Us details linked to from every page on the site.

There used to be a link to site admin in the rules - forum@hornby.com - but as it has been deleted I don’t know if that email is still active and monitored nowadays.

As suggested by others read the rules, (which are set by Hornby Towers across all brands, not by the moderators on this forum) before taking action, as following a report a review is made of those concerned’s posting history to see if the complaint is valid, are they are a serial pest or not, or is the report simply vindictive back biting (trolling) by the reporter, which is also against the rules.