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Old 13th Feb 2012, 17:48   #1 (permalink)
 
Join Date: May 2005
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A320 Flight Deck outlets - converting from 400 Hz - 60

The outlets in the A320 flight deck are 400 Hz. Does anybody have any history on your fleets converting them to 60 Hz? Or can anybody suggest an alternative solution for an approved power source for PEDs - laptops, cell phones, etc.
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Old 13th Feb 2012, 19:01   #2 (permalink)
 
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320 outlets

Most modern pc supplies will work at any voltage from 240 to 115 v and any frequency from 400 hz to 50 hz. Have a look at data plate on them.
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Old 13th Feb 2012, 20:47   #3 (permalink)
 
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Apparently that's not good enough to certify the installation as a power supply for something like an iPad in the flight Deck. Airbus even disavow that specifically.
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Old 15th Feb 2012, 09:38   #4 (permalink)
 
Join Date: Sep 2001
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Power outlets

I know that EasyJet have an inverter which is positioned directly over the forward E/E bay hatch. They use this solely to power two power outlet sockets below the DV windows-for their laptops.
They often fail..............
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Old 15th Feb 2012, 21:29   #5 (permalink)


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Actually they don't fail that often and when they do , a simple reset does the trick. we have more problems now with the outlets themselves.
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Old 18th Feb 2012, 12:11   #6 (permalink)
 
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hi there NCC0

we had the same issue with the outlets for laptops in my company and we found out that WEST AVIONICS (GERMAN COMPANY) is part 145 approved and can manufacture custom made chargers that are approved by EASA
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Old 18th Feb 2012, 14:19   #7 (permalink)
 
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The PED's don't care, the chargers/power supplies don't care, it is cleaner power, anyways the input is AC the output is DC.
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Old 25th Feb 2012, 08:19   #8 (permalink)
 
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Just plug your computer, tablet, phone etc. into the 400hz outlet, been doing it for years and never fried anything.
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Old 27th Feb 2012, 19:58   #9 (permalink)
 
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Quote:
PED's don't care, the chargers/power supplies don't care, it is cleaner power, anyways the input is AC the output is DC.
Quote:
Just plug your computer, tablet, phone etc. into the 400hz outlet, been doing it for years and never fried anything.
Both statements are basically true for modern gear.

An old tech "wall wart" power supply "might" run a bit warm if it has a (iron core) stepdown transformer directly connected to the line due to higher losses at 400Hz.

Almost all modern wall warts use a switching converter that runs from rectified DC, full wave bridge + fillter capacitor.
This allows the stepdown transformer to be mutch smaller (aka cheaper) since the frequency is >> 100Khz.

If anything they should run cooler since the input filter capacitors will be more effective at 400Hz than 50/60Hz.

On the other hand many (most?) are not tested/certified by the manufacture to run on other than 50/60Hz.

The real restriction is whether the relevant authorities recognize the unit as safe/suitable, hence the existence of kludges such as invertors to provide 60Hz.

When/if certification is required is totally outside my area of expertise.

BTW: Any equipment with a normal line cord (not a wall wart/DC supply) may have problems if fans or other motors are run directly from the AC power.

This is not commonly found in the consumer computer world but is sometimes seen in industrial gear or older consumer products such as tape recorders.
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Old 1st Mar 2012, 05:02   #10 (permalink)
 
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Quote:
The real restriction is whether the relevant authorities recognize the unit as safe/suitable, hence the existence of kludges such as invertors to provide 60Hz.
That's the issue at it's core isn't it. In order to install something as Basic equipment on the aircraft and satisfy our regulator to keep the aircraft on the AOC, we'd need to develop an STC and meet the certification standards for an appliance. To do otherwise would be to invalidate the Type Certificate.

Wouldn't the lawyers jump on that one when they sue because a bag fell out of an overhead and injured his client. Your honour - the aircraft was not even certified any longer and was not legal to fly yet they sold a ticket to my poor client ..........
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Old 2nd Mar 2012, 05:29   #11 (permalink)
 
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The Qantaslink 717s have just had laptop holders installed behind the FO's seat, with a charger too. If i recall correctly the laptop power supply brick is a standard unit, it's just wired directly from the CB panel. As others have said: Modern switchmode power supplies are pretty tolerant of input power variations.

No maintenance manuals on those laptops, though. That would make too much sense!
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Old 3rd Mar 2012, 07:50   #12 (permalink)
 
Join Date: May 2005
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I tried contacting WEST AVIONICS as Lochias had suggested for a custom power supply but never heard back.

I don't know how Qantaslink did it on their 717s without raising the ire of the CAA but I have to guess it was under the authority of an STC. I just doubt anybody would approve the STC.
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Old 7th Mar 2012, 15:26   #13 (permalink)
 
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Airbus have a service bulletin to install a small static inverter. Input 28VDC Output 115VAC 60 HZ 150VA output. It lives aft of the sidestick controller and provides power to an outlet located in the same area. We use these to charge lap tops and mobiles on our A320 AC. Installation is covered by Airbus SB 24-1097. The inverter is manufactured by Avionics Instruments inc. 1414 Randolph Ave. 498 NJ 07001 Avenel usa (Airbus vendor code 10933) Inverter P/N 1-002-0102-1830. Installation would take typically 10 MH per side. There may be a higher output model available, perhaps a talk with the manufacturer or Airbus would be useful.
Regards TC
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Old 7th Mar 2012, 22:44   #14 (permalink)
 
Join Date: Mar 2005
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Airbus won't give you access to that SB without applying officially for it (ie paying for it).

You'll need to apply to Airbus using the RFC/RMO procedure but it's a great starting point.
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