collapse

* Who's Online

  • Dot Guests: 20
  • Dot Hidden: 0
  • Dot Users: 1
  • Dot Users Online:

* Recent Topics/Posts

JHMCS Replica (WANTED) by nguymike
[Today at 08:05:29 PM]


henkie's wishlist by biggles
[Today at 06:05:14 PM]


Kukki´s Pit V5 by Kukki
[Today at 05:17:14 PM]


Internal lighting AAU-19/A by Dead-man
[Today at 05:06:15 PM]


Synchro Drive Interface (SDI) by Kukki
[Today at 05:05:23 PM]


John's F16 pit progress by JCook
[Today at 02:01:35 PM]


Mike's Money Pit by MrBones
[Today at 08:51:15 AM]


NO AI/ATC sound by sagrzmnky
[July 29, 2014, 11:45:48 PM]


(87th VFW) Blade's Pit Progress by Windmill31
[July 29, 2014, 05:10:12 AM]


Mark's AB-pit report by Snowman
[July 29, 2014, 04:15:29 AM]


PSCOCKPIT SYSTEM 3rd RUN! by Cupra
[July 28, 2014, 01:33:41 PM]


the USAF's deadliest F-16 Fighter Pilot Dan Hampton. by sagrzmnky
[July 27, 2014, 05:22:03 PM]


Mike´s Full ICP Kit and Vipercore PCB SOLD!! by Trigger
[July 26, 2014, 07:00:10 AM]


eBay heads-up by Goofy
[July 26, 2014, 04:35:10 AM]


bluc69 F16 Block 52 pit by Rufus
[July 25, 2014, 07:48:25 PM]


Usefull switch ? by mrwell
[July 25, 2014, 01:46:43 PM]


Willy's Pit by mogas
[July 25, 2014, 11:38:57 AM]


Grease Monkey's Pit by Cupra
[July 24, 2014, 01:37:55 PM]


Need HUD box by Manny
[July 23, 2014, 08:25:30 PM]


Entire Fam Pit for Sale. Pics, ebay link, etc... by clr4ils
[July 23, 2014, 06:17:47 PM]

Author Topic: Negative voltage at AIC backlight?  (Read 2306 times)

Offline Rufus

  • General
  • ******
  • Join Date: Feb 2012
  • Location: California
  • Posts: 1276
  • Country: us
Re: Negative voltage at AIC backlight?
« Reply #60 on: December 23, 2013, 02:11:22 AM »
Ok...I think I've noodled something out about the Mean Well supply.  I went back and looked at the block diagram again, and it appears that while the G/G (COM, in the diagram) and mains earth may not be directly tied together they are internally shared somehow - with with a capacitor between the high side and mains earth presumably to create some delay/over voltage protection for given channels.  But it looks as if the circuit branches are self-draining at shut down, so nothing to worry about there.

I'm thinking though that I shouldn't ground my pit structure to/through the supply earth though, because a back EMF could harm the protective capacitors...but that I can use the wall plug ground over a separate cord with only the ground wire connected?  I'd lift this circuit with a relay at MAIN POWER - other than OFF, maybe with a slight delay.
- Rufus

Offline Cupra

  • General
  • ******
  • Join Date: Jun 2009
  • Location: Solothurn
  • Posts: 761
  • Country: ch
    • 1st VFW "Glory Wings"
Re: Negative voltage at AIC backlight?
« Reply #61 on: December 23, 2013, 02:17:28 AM »
@dkm
Oops, that has gone under... or how ever you say  :harhar:

Yes, everything else is working without anny issues. Boards are dedected and at the power supply Pins of the boards the +12V DC is stable with the Switch on and it is 0,00 when the Switch is off.
The exact same circuit (a second one) is connectet to the backlight-connectors and there I have the -14V when i Switch off. But bowth funktions are working without problems or thermal abnormalities.
So for me I would say if eveything works proper there is no Need to do anything... I am just always a litte afraid if I have voltages I can´t explain  :notes: