PM system Power Problem

[Peter Nielsen]

<meta http-equiv="Content-Type" content="text/html; charset=utf-8"><meta name="ProgId" content="Word.Document"><meta name="Generator" content="Microsoft Word 10"><meta name="Originator" content="Microsoft Word 10"><link rel="File-List" href="file:///C:%5CDOCUME%7E1%5CPINGER%7E1%5CLOCALS%7E1%5CTemp%5Cmsohtml1%5C01%5Cclip_filelist.xml"><!--[if gte mso 9]><xml> <w:WordDocument> <w:View>Normal</w:View> <w:Zoom>0</w:Zoom> <w:Compatibility> <w:BreakWrappedTables/> <w:SnapToGridInCell/> <w:WrapTextWithPunct/> <w:UseAsianBreakRules/> </w:Compatibility> <w:BrowserLevel>MicrosoftInternetExplorer4</w:BrowserLevel> </w:WordDocument> </xml><![endif]--><style> <!-- /* Style Definitions */ p.MsoNormal, li.MsoNormal, div.MsoNormal {mso-style-parent:""; margin:0cm; margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:12.0pt; font-family:"Times New Roman"; mso-fareast-font-family:"Times New Roman";} @page Section1 {size:612.0pt 792.0pt; margin:72.0pt 90.0pt 72.0pt 90.0pt; mso-header-margin:36.0pt; mso-footer-margin:36.0pt; mso-paper-source:0;} div.Section1 {page:Section1;} --> </style><!--[if gte mso 10]> <style> /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:"Times New Roman";} </style> <![endif]--> Hi,


I am since a few months having a reoccurring problem with PM system which I so far am unable to solve.

I run PM systems and have the entire overhead wired up using Phidgets and all works fine. However totally at random, sometimes during Taxi, some times during Climb and sometimes during Cruise (But NEVER on decent) the PM SYS software toggles the Battery back to OFF and the entire overhead goes dark, engines cut off.

I then can’t get the overhead hardware knobs or switches to respond for a period of time between 2 and 5 mnts and have to use the mouse to toggle the Software battery back on and then do an in flight restart.

This is now happening on each and every flight with an average of 2 to 3 times per flight, there is no actual sequence as to this, ie after a set nbr of minutes or when passing a certain altitude but totally at random.

I wonder if anyone is or has had this problem or you may have an idea of why this is occurring.
Kind regards
Peter

[metamarty]

This sounds like a voltage problem in the USB system. I also have an overhead panel completely filled with phidgets hardware. What we found was that on some occasions, phidgets cards were dropped from the list of active hardware and later automatically reconnected. It turned out that when using power, the USB hubs and phidgets LED cards started switching themselves off because the total voltage started to drop too low.

Try powering phidget led cards at 12 volts if you have them powered at 6 volts. I don't have PMSystems, but this sounds like a phidgets voltage problem.