+5VDC terminal.. is is hard wired to the PWR jack?

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clearwaterbrewer
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+5VDC terminal.. is is hard wired to the PWR jack?

Post by clearwaterbrewer »

If we wanted to provide a 'wired terminal' power input to the BCS, could we use the +5VDC and GND terminals?

Background.. I want a cleaner and more volumetric-ally (sp?)solution than a wallwort plug, the outlet, and associated items.. I found a reasonable and high quality 5vdc supply that supplies 2A and has a cord. Made for Cisco Analog Telephone Adapters, the ADP-10UB can be found very cheaply. The plan would be for it to be hard wired to 120V inside my cabinet (without needing the space of an outlet and enclosure), Velcro to some spot that is convenient, wired with a 2A fuse to a bus-bar where all +5V items are, then a small fused wire goes to the BCS and I won't bump it and reset the controller if I am fiddling in my cabinet.

-mike
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Re: +5VDC terminal.. is is hard wired to the PWR jack?

Post by JonW »

Why not just snip the cord from the original power supply and wire that to your new 5V power distro and plug it into the BCS? I have to imagine there is a voltage regulator and some protection diodes at the input jack that probably wouldn't be in the loop if you supplied power directly to the 5V output.
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Re: +5VDC terminal.. is is hard wired to the PWR jack?

Post by clearwaterbrewer »

JonW wrote:Why not just snip the cord from the original power supply and wire that to your new 5V power distro and plug it into the BCS? I have to imagine there is a voltage regulator and some protection diodes at the input jack that probably wouldn't be in the loop if you supplied power directly to the 5V output.
Jon -
What you are imagining is why I am asking.. ;-)

That plug is not exactly 'secure'... I am afraid that someday I will fiddle around with something near it and it gets loose and the thing resets during a brew session..
-mike
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Re: +5VDC terminal.. is is hard wired to the PWR jack?

Post by JonW »

OK, instead of imagining it, I looked at the specs. The wiki lists the input specs as being 6-10 vdc which means that there definitely is a voltage regulator on the input. Now technically, depending how the traces are setup, you may be able to do what you want. However, you'll be bypassing all input protection of the board which will also include any caps on the input (after the voltage regulator) that will control voltage ripple as well.

Did you measure the voltage output of the Cisco power supply? Almost all DC voltage power supplies put out a few volts over their rated output. I wouldn't put the board at risk by trying to back-feed 5V into the aux jack.
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Re: +5VDC terminal.. is is hard wired to the PWR jack?

Post by clearwaterbrewer »

I just wanted to figure it out without opening it, which I can do I guess... I did probably just void my warranty (not the first time, that was powering it via USB) by hooking it up and verifying that it does work just fine being powered by the terminals and not the barrel connector ... been going for a couple hours now and at 5.16V.

Next step is to measure the current my Xbox Wireless adapter uses(also 5V), and possibly get rid of one more wall wort inside my enclosure...
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Re: +5VDC terminal.. is is hard wired to the PWR jack?

Post by ECC »

No, the +5vdc pin is not hardwired to the pwr pin. There are 2 internal regulators, one 5v that goes to the I/O chips (and the 5vdc pin), and a 3.3v that feeds the main microcontroller/communications. Both regs are fed by the barrel connector, which needs to be 6v to account for the voltage drop of the 5v regulator. Less than 6v will probably work most of the time, but you are out of spec.

If you're feeding the +5vdc pin with 5v, I'm not sure how the 3.3v domain is getting supplied, unless the 5v reg is doing some strange backfeeding or something. In any case, not recommended. Sure, its possible to mod the BCS to make that work, but then you're at the mercy of an untested power supply and possibly noisy, etc.

There are some very simple and cheap connectors that someone found on another thread that allow the transformer to be used without a full outlet..
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Re: +5VDC terminal.. is is hard wired to the PWR jack?

Post by clearwaterbrewer »

Interesting.... that is why it probably does not have network connectivity when I place the load of my 5VDC powered Wireless adapter on the same power source... just goes that little extra out of spec...

Thank you so much for the description of how the power works... I will be providing power from now on via the proper connector, will devise a clip or hot-glue it in place...

-mike

Oh, for others, a DIN mounted power strip from automation direct may be usable and take less space than an entire outlet box
http://www.automationdirect.com/adc/Sho ... ts/FA-REC3
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clearwaterbrewer
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Re: +5VDC terminal.. is is hard wired to the PWR jack?

Post by clearwaterbrewer »

hmmm.. 5VDC wireless adapter that takes 400mA and BCS that takes 200mA are not reachable(but BCS works) when on same 5VDC 1700mA power supply (I had a Kyocera camera one laying around)... need to troubleshoot some more..

OK, wow... plugged all 5V stuff into a small breadboard so I could measure in-circuit, I powered the BCS (via barrel jack :-) and relay board from my 1700mA power supply.. it is fine at 5.14V
However, the XBOX MN-740 connected to its own PS that came with it in the box, but wires stripped , tinned and in breadboard using common ground, but different set of holes for the voltage... it is 13V what? the Xbox wireless g adapter says plain as day 6V on the bottom, but the PS that came with it and that has been working for 6 months is 12V???... weird... no wonder it did nto work when connected to the 5V supply... searching the numbers on the label of the wall wort (ad48-0100 and E312169 ) do not yield much, but not a big deal, I just wired the 12V strobe I have to this PS, I and at least down to 2 power supplies, and both have 'cords' that I can strip and connect to my 120V bus, and velcro up somewhere convenient in the cabinet.
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ECC
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Re: +5VDC terminal.. is is hard wired to the PWR jack?

Post by ECC »

Something like this is pretty efficient.
http://www.amazon.com/Leviton-1306-Snap ... B003AULTMA
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