Disconnecting USB while RM is running

[Augustus Caesar]

Here's a curiosity question for some of you...

Because I have disconnected evrything from the test track I was running while getting ready to add a pullout shelf for the laptop etc and then fix the eLink to a side wall of the built up units I cannot test this simple but possibly pointless exercise :-)

 

OK... while RailMaster is running, whether while using it to just simply run at its pure simplest or whether running programmes written for serious stuff etc... if you were to pull the USB plug, on purpose or accidently, would the system just keep running and therefore cause an issue re a pile up etc... or would it STOP?

 

I cannot see the latter happening but it became something of a thought when I was dismantling my test track  and cables and now it is slightly bugging me. I would assume the loco's etc would still keep going especially on a simple operation.

 

However, when a programme is running and the cable is pulled would that just keep going? The answer is probably yes. BUT... what if when the cable is reconnected... and the system doesn't recognise or pick it up what then?

 

Should there be a fail safe built in to RM as it monitors the USB connection and if the connection is detected as lost then the system could be brought to a halt? This will almost certainly mean a firmware change to the eLink unit but it COULD be added as a software check... which would possibly slow down the system and be prone to error on its own. So firmware would be the best way to go?

 

Maybe HRMS can answer this one... as I said it is a curiosity thing more than anything else but if thought about it could actually cause one person, somewhere down the line, a big headache.

 

Any thoughts?

[Nick_]

I would assume that the e-link would notice that the USB connection had failed, the comms must be bi-directional, and would either cut power to its output or send an ALL STOP. Today I'm running-in some new locos so I'm operating my layout in DC mode thus I can't test it myself, but I guess HRMS would know the answer.

[Hairy]

Just pulled my USB lead, loco kept running.

Plugged USB lead back in, RM didn't reconnect to elink so had to switch power off.

[Augustus Caesar]

Just pulled my USB lead, loco kept running.

Plugged USB lead back in, RM didn't reconnect to elink so had to switch power off.

 Well Hairy...

 

Thanks for that confirmation. I had an idea the loco's would still run but it was just a curiosity thing re the USB connection once the cable was pulled from the eLink unit and reconnected.

 

That's actually very interesting but I wonder whether or not HRMS will actually come back with anything on this one? It's not a thing one would do naturally, of course, but accidents happen. So if the cable is pulled accidently then... what are the suggested operations to stop the loco's running amok? As you said, on your system, the USB connection was NOT remade.

 

That leaves a situation for potential chaos doesn't it? If one of the shows has a demo working well and suddenly the cable is released from its housing (the USB socket) and when plugged back in it doesn't respond... well, it leaves a situation where a very quick pull of the mains would ensue.

 

You couldn't simply press ALL STOP, or have it done automatically as things stand - as Nick_C says, because it wouldn't have a connection to RM...

 

Thoughts on this one HRMS? 

[ColinE]

When I first started using RM I had a few instances where, though inexperience, I lost control and could not operate the All Stop button quickly enough to avoid a coming together !!! To prevent this situation happening I fitted a switch in the DCC feed wire between the e-link and the DCC bus on the layout, painted it red and sited it in a prominent place. It has since proved invaluable as when I get a computer glitch a quick flick of the switch brings everything to a halt without dropping out the e-link/computer connection. In your scenario of pulling the usb cable out accidentally using the switch would bring everything to a halt without having to scrabble around for the mains plug, of course you wouldn't maintain connectivity between the e-link/computer but at least nothing would be moving.

[Augustus Caesar]

When I first started using RM I had a few instances where, though inexperience, I lost control and could not operate the All Stop button quickly enough to avoid a coming together !!! To prevent this situation happening I fitted a switch in the DCC feed wire between the e-link and the DCC bus on the layout, painted it red and sited it in a prominent place. It has since proved invaluable as when I get a computer glitch a quick flick of the switch brings everything to a halt without dropping out the e-link/computer connection. In your scenario of pulling the usb cable out accidentally using the switch would bring everything to a halt without having to scrabble around for the mains plug, of course you wouldn't maintain connectivity between the e-link/computer but at least nothing would be moving.

Hi Colin...

 

You also make a very interesting contribution with the switch idea. Obviously this is something that does work and is not just theoretical. Now far be it for me to ask Hornby or the makers of RM or the eLink to bring out such a switch for the user to add to their layout as a sort of default but it would make sense. It seems that at least some members are experiencing this in one form or another.

 

Can you explain the switch you used (and where purchased maybe) and the procedure for wiring this into the circuit? I'm not saying I will have one of these times where the switch will come in handy but as I build the layout and begin wiring any day now it will be a bonus worth having and as it can be added anywhere along the cable length it can be hidden but known where it is for that emergency should it arise... and it invariably will. Hopefully you can give us that info even for future purposes.

 

If you wish you could even e-mail the details using the link on the RM support page I have built up recently and the link to which is fixed at the top of the RM threads. If you give permission I can add those to the site with full credit given to you. Of course, if you'd rather not, then no problem though it may help others along the way.

 

 

[RobinJ]

Duplicate Post: Removed

[RobinJ]

When I first started using RM I had a few instances where, though inexperience, I lost control and could not operate the All Stop button quickly enough to avoid a coming together !!! To prevent this situation happening I fitted a switch in the DCC feed wire between the e-link and the DCC bus on the layout, painted it red and sited it in a prominent place. It has since proved invaluable as when I get a computer glitch a quick flick of the switch brings everything to a halt without dropping out the e-link/computer connection. In your scenario of pulling the usb cable out accidentally using the switch would bring everything to a halt without having to scrabble around for the mains plug, of course you wouldn't maintain connectivity between the e-link/computer but at least nothing would be moving.

Interesting idea! I cant help think that the eLink should have had one built in to start though (like the Z-21). Emergency stop buttons can be purchased here: http://cpc.farnell.com/webapp/wcs/stores/servlet/Search?st=emergency+stop&catalogId=15002&categoryId=700000011805&langId=69&storeId=10180 most of them are twist to reset and would just need wiring inline with either the A or B wire (or both if the switch is dual pole).  

[ColinE]

Hi AC, I just used a simple single pole miniature toggle switch which you can buy in Maplins for a couple of pound. I looked at proper emergency stop switches but they were too expensive and the miniature toggle switch was less obtrusive. I simply broke into one wire of the twin core cable that Hornby supply to go between the layout bus and the e-link and inserted the switch. Just remember though if you do fit this switch and on start up nothing moves check the switch before swearing, as you can tell I accidentally knocked into the off position once !!!! Hope this helps.

[Augustus Caesar]

Thanks Colin for the info. I'll probably put a couple of wires onto the original to extend it and place the toggle in the area of the joins. That way I can remove it if need be later in the future and still have the original length Hornby cable.

Can you offer up the model number or Maplin catalogue number for the particular switch you bought?

[NormanQ4]

Couldn't you just place the eLink in an easily accessible position and pull the power cable?

[ColinE]

Couldn't you just place the eLink in an easily accessible position and pull the power cable?

Yes you could just pull the power lead but but then to restart you would have reboot and reconnect e-link/railmaster whereas with the switch you just put it back on to resume playing.

[Augustus Caesar]

Pulling power cables from any socket is not a good idea. There is a risk of a short being caused (not high I know) but also of there being a greater risk of loosening the solder connecting the socket to the main board inside the eLink.

I mention this because of the high amount of laptops I fix where users have been a little over zealous at cutting power to their laptops instaed of pulling the socket from the wall outlet and also forcing the plug into the socket of the machine as well.

However, having said alll that, it is not always going to be easy Norman for everyone to just lean over and pull a cable from the eLink or whatever. It may not be easily accessed for one....

Colin... apologies for a second pop at the question... do you have a model number for that switch... or I could just search for your description of the unit on Maplins site?

[NormanQ4]

On the subject of accessibility, would kill switches wired in series (I think that's the terminology) around the perimeter of the layout at say 2.5 - 3 metre spacing be a practical solution?

This is my current thinking but I'm interested in the pros and cons of this idea.

With regard to cutting the power while a programme is running, what if any would be the likely outcome?

[Augustus Caesar]

On the subject of accessibility, would kill switches wired in series (I think that's the terminology) around the perimeter of the layout at say 2.5 - 3 metre spacing be a practical solution?

This is my current thinking but I'm interested in the pros and cons of this idea.

With regard to cutting the power while a programme is running, what if any would be the likely outcome?

I don't know about placing more than one switch around the track unless you have indivdual track with its own power supply. I would automatically assume that one switch would be quite sufficient to cut power to all track if it is wired, say, with a system bus setup. From that you have one pro and one con so not really conclusive either way unfortunately.

As Hairy pointed out when he pulled the plug everything kept going and upon reconnection of the USB cable the eLink had lost all communication so power had to be turned off. From this I assume too that whether or not a program is running or the eLink is just under simple control and not setup to run a program the outcome would be the same. All loco's would keep going and USB comms would be down until an all stop with a power cut and reconnection can be made.

Of course, if the Hornby is clever and remembers the command strings, it may just stop by itself naturally when under a program. That's an interesting point. However, I am unable to test it and would need to rely on someone else until I get all my wiring done and track laid down. Hmmm... anyone willing to give this a pop?

[ColinE]

Pulling power cables from any socket is not a good idea. There is a risk of a short being caused (not high I know) but also of there being a greater risk of loosening the solder connecting the socket to the main board inside the eLink.

I mention this because of the high amount of laptops I fix where users have been a little over zealous at cutting power to their laptops instaed of pulling the socket from the wall outlet and also forcing the plug into the socket of the machine as well.

However, having said alll that, it is not always going to be easy Norman for everyone to just lean over and pull a cable from the eLink or whatever. It may not be easily accessed for one....

Colin... apologies for a second pop at the question... do you have a model number for that switch... or I could just search for your description of the unit on Maplins site?

 

 Hi sorry for the delay. The switch I used was a Radio Spares 316-969 which I had in my electrical box. I don't even know whether they are still made as it was old. I suggested Maplins as most people have one near them. Any switch will do but the most important aspect is the current rating. If you are using a 1amp power pack to run the layout then a 1amp sub miniature switch like mine will be fine, if you are using a 4 amp power pack then a 4 amp (or more) rated switch is needed. A car toggle switch from your local car accessories dealer would be fine. Hope this helps.

Colin

 

[Augustus Caesar]

Pulling power cables from any socket is not a good idea. There is a risk of a short being caused (not high I know) but also of there being a greater risk of loosening the solder connecting the socket to the main board inside the eLink.

I mention this because of the high amount of laptops I fix where users have been a little over zealous at cutting power to their laptops instaed of pulling the socket from the wall outlet and also forcing the plug into the socket of the machine as well.

However, having said alll that, it is not always going to be easy Norman for everyone to just lean over and pull a cable from the eLink or whatever. It may not be easily accessed for one....

Colin... apologies for a second pop at the question... do you have a model number for that switch... or I could just search for your description of the unit on Maplins site?

 

 Hi sorry for the delay. The switch I used was a Radio Spares 316-969 which I had in my electrical box. I don't even know whether they are still made as it was old. I suggested Maplins as most people have one near them. Any switch will do but the most important aspect is the current rating. If you are using a 1amp power pack to run the layout then a 1amp sub miniature switch like mine will be fine, if you are using a 4 amp power pack then a 4 amp (or more) rated switch is needed. A car toggle switch from your local car accessories dealer would be fine. Hope this helps.

Colin

 

Cheers for that info Colin... great help! No matter the length of time of any delay for it though as I have time on my hands while building a pullout shelf for the laptop and more ready for operating the layout.

I'll check out the model you menton and have a natter with my older brother as he may have a decent equivalent if nothing else he can just give me. If not then Maplins will offer something close enough I am sre. I'll probably get the higher rated version where amps are concerned because I feel I may just need it... :-)

Thanks again Colin...