"Hardware Status" in NION

Rule of thumb:  5mA phantom power current per channel. 

At 5mA you can expect 48V to droop down to 31.5V.  (48V - (5mA * 3.3kOhms)).  Each channel will have a droop that depends on its unique current draw.

I did a microphone spec sheet survey a while back and discovered that most phantom powered microphones draw far less than 1mA.  Someone measured 13mA pulled by those michrophones with the bright blue LED's.  I remember that their manufacturer advertised far less than 13mA draw, seems like it was more like 7mA.  Could we be talking about these same michrophones again?

All Nion Cards use the +/- 24V rails to develop +/-15V analog rails AND +48V Phantom power.  The 24V supplies are developed on the Nion mother board.  I think a DC/DC up converter is used to do this.  So power limits are a function of the ATX supply limits and the DC/DC converter limits.

In response to the 1st question, the power monitoring in Nion is just monitoring.  The off-the-shelf ATX power supply shuts down its supply rails if too much current is drawn.  Any Nion rebooting/power cycling is caused by too much current demand on the ATX power supply.

Nio 8i cards don't have phantom power, and they use quite a less +/-15V rail power than the 8ml-ll cards.  Sounds like the Nion may not be pulling enough current from the +24V rail to properly regulate the voltage.  Many power supplies will shut down if a minimum current is not drawn from the supply.  I wonder if that is part of the problem your first fellow mentioned below is having.  Or perhaps the jump in voltage is a clue that his power may have spikes that send the unit into reboot.  If so, perhaps some power conditioning is in order?

Unfortunately I don't have a fixed number answer for your last question because there are too many variables at play.  The combination of Nio cards in a Nion and how these cards are configured in the GUI will determine an actual current load on the 24V DC/DC converter and the ATX power supply.  So for a particular Nion configuration, there will be a unique amount of current margin available for phantom power.  If more current is required than is available you will have power up and or reboot problems.  By experiment, one could determine how many microphones they can safely power without causing a reboot.  If more phantom power is needed than can be safely provided a particular Nion configuration, then external phantom power supplies should be obtained and used.

A higher power ATX power supply and or DC/DC converter might increase the total current available for Phantom Powered devices.  The Nio cards will supply up to 5mA per channel up to the point that the Nion's power supply shuts down.

That's all I can offer for now.

I have recently noticed that power supply voltages vary from unit to unit. The normal voltages provided by the ATX supply are generally within 1 or 2% but the voltages produced by the NIONs are +/- 4.5% or so. My test file has a +/- 5% tolerance and I haven't had a failure yet.  Perhaps I need more information on what tolerance to test to. Failure is set at 25.2 VDC or 24V x 1.05.

Hi Phil-

I have been doing a bit of testing on a NION here to see just exactly how much draw I can put on the Phantom Power Supply before things fold up shop. As near as I can tell, as long as the total phantom power required by the microphones is 250mA (that is 250 milliAmps, or about a quarter of one Amp) or less you will be fine.

According to what Mark had noted above, via Scott (Fergy), most microphones require less than 1mA of current from the Phantom Power supply. This means that you will have no problem loading up all 32 inputs with ml II cards as you would be at less than 32mA total. Now, where you may get into some trouble is if you have microphones that require a large amount of phantom power. If your microphones require 8mA per channel or more, you will most likely not be able to plug 32 mics into one NION.

You will notice that as you start to load up the NION with phantom powered microphones, the voltage on the 24V rails will start to sag. It can sag all the way down to 21.6V without issue, but as soon as it hits 21.5V the audio will stop and the error will state "Voltage Out-Of-Range". I am fairly certain that there is something to do with the voltage monitoring in the NION stopping the audio since the actual voltage rails are being reported as still being up, just not up high enough.

So, to actually answer your question, as long as the consultant's microphones require 10mA or less, he can put 24 of them on the NION with no problem.

I am very interested to hear what issues other people may be having with the NION's phantom power supply.

Have there been any further experiences with phantom power, particularly with the NioAEC card?

I see I never confirmed Phil’s last post, but here is what I know; phantom power is the only thing that uses 24 volts on the NIO-Card (whether 4x4, 8ml-II or AEC), everything else uses other rails -+12, -+5).