c.meynell
Hi all

This diagram is useful to describe the principle. DCC controls the accessories while DC drives the trains.

Note: the Cobalt iP Digitals will have to use the SPDT switch to power the frog and not that handy connection #3.

pdf Stand-Alone Accessory Bus for DC or DCC users.pdf     

pdf Cobalt iP Digital wired from an Accessory bus.pdf     

We don't recommend using the sniffer for solenoid decoders .
All the best

Chris
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lil chris
Hi there I have used the sniffer to make a bus for 17 Digital IP motors with a Cobalt Aplha central,I had it working fine. I then extended the sniffer bus and connected 2 more Ip motors and 4 anolouge motors using 2 AD2FX accessory decoders and a Aplha encoder connected with the small cable to the Alpha central. I could not get that to work, both units light up, the trouble is the 17 original motors no longer work. When I first connected upI got a red light on the sniffer but disconnecting and powering off it changed to blue but nothing works. The sniffer seems to be working intermittently,I disconnected the extended bus and athe Alpha encoder and I managed to get the Alpha central working with the 17 motors again now even though I have a blue light on the sniffer it no longer works again, I have tried several times re-cycling the power with no effect.
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AHJAY
You are trying to draw more power than the "Accessory bus system" can deliver. Therefore it is shutting down.

The symptom of red then blue on re-start is a clear indicator of this - its at its maximum load limit so the turn on surge shuts it down, but as some capacitance is already pre-charged on the repeat turn on, there is JUST enough to let it stay on... but not to poerate normally)

The problem MAY be the power supply has reached its limit but it is far more likely that the overall combination exceeds the power limit of the Sniffer, which was not designed to be an Accessory bus supply for a larger layout.

I suspect that you will need to move to an Alpha Power and Alpha box to give adequate power.

Regards, Ahjay
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lil chris
Thanks Ahjay, I suspected lack of power was the problem, since I posted  I rung up for advice on Wednesday and I have bought off you a Alpha box  along with a Alpha panel and a Alpha Mimic set. . Roger also explained I need 3 wires to each of my manual switches, so my setup would not have worked anyway. He has now supplied switches for me so I should now be up and running soon. The parcel arrived Saturday Morning so fantastic service from you guys. Keep Safe. Chris H
Ps I forgot to ask Roger said my power supply for the sniffer should be ok for the Alpha box. It only says 13.8v, the documentation for the Alpha box says it requires 15-18v. I will see how it goes when I connect up hopefully tomorrow.
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lil chris
Well things have improved over the Sniffer. The Alpha central is working using 1-12, so I disconnected it while I programmed the AEU(13---on), all went well, I programmed the anolouge motors with the AD2fx decoders ok. The trouble is when I plug both units into the Alpha panel nothing works, so I think it still may be a lack of power, perhaps the 13.8v is not enough.
I will probably ring up tomorrow and order a power supply of some sort. Something I have found out is the faulty Cobalt IP I have responded to number 1 on the Alpha central in fact all the anolouge motors via the AD2FX's responded until I re programmed them on the AEU. It will not take a change of address command though, I want to use number 12 on the Alpha Central, fortunately it works off the switch I have attached to it. I have just thought of something, I noticed they both come up with 4 when you turn them on, do the two units need to have a different address to each other with not being linked together with the small cable. Keep Safe everyone.
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AHJAY
Your issue will not be voltage, because Alpha and Cobalt are quite tolerant of that sort of variance.

If it is power supply related (probable) It will be available power (amps). Overall if its a simple "Wall plug" of any type the loading you have will probably take it to its limit. You will need to move to a better power supply. You will get unpredictable results with any digital device if the power supply is stressed.

If it is overall system load exceeding the Sniffers ratings (possible) then you will need to move to an Alha box. You will get unpredictable results with any digital device if you ask it to work at above rated output.

Overall the best answer WILL be an Alpha box and Alpha Power.... a 5 amp combination that will give you lots of power for future expansion

Ahjay
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m.bryan
Hi Chris,
I believe you'll be all sorted (for now) after our phone chat.
You've swapped out the Alpha Sniffer for Alpha Box
Whilst the Alpha Box will work with the 13.8v power supply and accessories, should you get an (unlikely) short on the accessory bus, it will be the power supply that will have to react to it - not the Alpha Box - as it will quite happily push through the 1.5-2A of the power supply and not trip.

Also as per call, daisy-chained Centrals or AEUs are treated as one cab - separate Centrals or AEUs are individual cabs and require individual cab numbers - so swap your AEU to 05 for example.

Mick
DCCConcepts Tech/Customer support
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lil chris
Thanks Mick, I changed the AEU cab number to 5 has you reccomended and all is working correctly. After my call with you I bought another Mimic set to compliment the one bought already, I also topped up my solder and flux supplies I was geting a bit low. Thanks for the support, I think I will be ok with setting up the mimic boards now I understand how they work,but at least I know who to call if I have a problem.
Thanks Ahjay, this layout will not be going any bigger, the wife thinks this layout is smaller than my last one it is actually bigger. Keep Safe guys.
Chris
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