No USB charge bricks needed while on shore power...

Did you know that even GFI recepticals use power while nothing is plugged into them? It is only a few watts per hour, per GFI, but still a GFI consumes power, and might cause a solar powered home to require installing extra panels due ot the wattage used by the wall warts and GFI recepticals.

I didn't know this! Apparently older ones did not use power but the newer, smarter ones draw about 5 mA, which is P=IV = .005x120 = 0.6 watts. Or 0.6 watt-hours of energy every hour. Not much for one but the trend is to put a lot of GFIs into homes and garages.
http://forums.jlconline.com/forums/showthread.php?53902-AFCI-amp-GFCI-Power-CGonsumption

It amounts to 5 KW hours a year, which could cost as much as a dollar. For each GFI in the house. I think I will stock up on the older kind that doesn't use power if there are any left.

Some AC adapters are very well made and feel cool to the touch so their parasitic draw must be similar to the GFI. But others are warm all the time and waste a LOT of energy.

mlts22 wrote:
Call me crazy, but what I would like to see would be a device similar to a USB hub with 4+ ports on it. It would have about 10Ah of lithium-ion batteries in it, and would get power either from the 120VAC section or charge from the 12 volt side. If on the 12 volt side, the electronics would be smart enough to switch everything off if the battery voltage goes under 12.2 volts so it won't cause damage. With the inbuilt battery, there can be a circuit that can watch the 12 volt side without having a parasitic drain once it gets disconnected.

When charging, when it reaches less than 5-10% charge, the device will stop charging anything on the USB ports.

The benefit of this would be that an iPad would have 4-5 hours of charging (smaller devices pulling 500 milliamps could charge most of the day) even if there are quiet times for generators. This also will allow for more time charging if one is running off of solar and such. Plus, it also adds a buffer, should the 120VAC side is having extremely dirty power with extended sags.

Have the battery in a compartment, then its output outlet for charging on a wall. That way, it can be placed in a useful spot.

That would not be a difficult request.

The 18650 battery that I have for some rechargeable flashlights is available in 5 amp hour capacity, and is 3.7 volts. So two of those will equal the voltage of a USB port. 4 would allow the system to have 10 AH instead of 5Ah. A simple DC power supply can regulate the 7.4 volts from the battery to the correct output voltage for the USB port charger. Rating it at over 3 amps output per hour would also not be a difficult request.

Charging from both 12 VDC and 120 VAC would add some unnecessary complications. Why have a 120 - 12 VDC converter, of the RV already has one. A charger that recharges the battery while the input is above 12.5 VDC will recharge the battery, and disconnect at lower battery input voltage.

Fred.

You're WAY over complicating it. Just buy one of THESE and leave it plugged in.

Call me crazy, but what I would like to see would be a device similar to a USB hub with 4+ ports on it. It would have about 10Ah of lithium-ion batteries in it, and would get power either from the 120VAC section or charge from the 12 volt side. If on the 12 volt side, the electronics would be smart enough to switch everything off if the battery voltage goes under 12.2 volts so it won't cause damage. With the inbuilt battery, there can be a circuit that can watch the 12 volt side without having a parasitic drain once it gets disconnected.

When charging, when it reaches less than 5-10% charge, the device will stop charging anything on the USB ports.

The benefit of this would be that an iPad would have 4-5 hours of charging (smaller devices pulling 500 milliamps could charge most of the day) even if there are quiet times for generators. This also will allow for more time charging if one is running off of solar and such. Plus, it also adds a buffer, should the 120VAC side is having extremely dirty power with extended sags.

Have the battery in a compartment, then its output outlet for charging on a wall. That way, it can be placed in a useful spot.

ksg5000 wrote:
Why not use something like this - less than $10 and no installation.

This is what other poster called "wall wart" or "USB brick". Draws power without load, yes. Better to remove when not in use, mostly for safety reasons so that it won't cause problems when you are not there.

I wouldn't worry about extra energy drawn by those flush outlets in idling mode. It draws 0.05-0.2W depending on model, this is max 0.4 AH over 24 hours. If you have 4 of them, it's still 1.6 AH or less. Do you really need more than 4? :)

Wall warts - I would suspect they draw more. Flush mounts sold in stores like Home Depot or Lowes are from Leviton and other brands that have been making residential 120V outlets for decades, they are certified, otherwise stores wouldn't sell it. Bricks from Amazon are made by God knows who, don't expect any standards of safety and quality - but then again, it can be easily removed when not in use.

There are a few receptacles that allow full use of the 120v outlet AND your USB device.

Why not use something like this - less than $10 and no installation.

I like this charger. You can install it in a cabinet or replace a cigarette lighter on your dash.

http://www.amazon.com/Blue-Sea-Dual-Charger-Socket/dp/B0082CXEI8

Eric

wkswenson wrote:
Clicky

Just be careful as these require a full depth electrical box and many RVs have shallow boxes. But great technology.

Actually RV and mobile home receptacles don't require any box. The one shown and all residential/commercial receptacles must be installed in an approved electrical box.

Nowhere does it spec either individual or total USB charge current. But it DOES say in the very small print (sic) that if you want your iPad to charge at the same rate as the Apple adapter (2.1A), use the cube.

I'm out