usb charging

Bosun Higgs

Bosun Higgs

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getting ready for the annual trip round lands end to the summer mooring, I've just noticed how many gadgets I'm taking with me that need usb charging - kindle, tablet, phones, mifi. 5 in all. I would appreciate adivice:

1/ they all use the same mini usb plug and socket but does that mean they can all use the same charger outputting a standard voltage. Related to that, where is the mechanism that controls charge level and switches the charger off - in the gadget itself or in the charger plug ( mains or ciggy lighter socket)

2/ has anyone found a good way of building multiple sockets into a boat? At the moment my choice is one ciggy socket 12v charger or using a small inverter with both 240 v and a usb socket.
 
Bosun Higgs said:
getting ready for the annual trip round lands end to the summer mooring, I've just noticed how many gadgets I'm taking with me that need usb charging - kindle, tablet, phones, mifi. 5 in all. I would appreciate adivice:

1/ they all use the same mini usb plug and socket but does that mean they can all use the same charger outputting a standard voltage. Related to that, where is the mechanism that controls charge level and switches the charger off - in the gadget itself or in the charger plug ( mains or ciggy lighter socket)

2/ has anyone found a good way of building multiple sockets into a boat? At the moment my choice is one ciggy socket 12v charger or using a small inverter with both 240 v and a usb socket.
Click to expand...

Best I've found has just two USB sockets, bit cheaper than Maby's one though!

http://www.maplin.co.uk/12v-twin-cigarette-socket-adaptor-with-2-x-usb-charging-sockets-228620
 
Installed 4 way ciggy socket (from Maplin) at the chart table, one in main cabin, aft cabin and one in fwd cabin! Each has a USB charging output also. Keeps everyone happy
 
I have a ciggy socket and a usb socket at the chart table, and onother pair in the saloon, and this covers most eventualities.

However, before installing a usb socket, be sure that uit is rated at 2A. Many will only supply 1A, and will only charge small devices such as phones, but may fail if you ever try o charge an iPad.

J
 
RestlessL said:
I have a ciggy socket and a usb socket at the chart table, and onother pair in the saloon, and this covers most eventualities.

However, before installing a usb socket, be sure that uit is rated at 2A. Many will only supply 1A, and will only charge small devices such as phones, but may fail if you ever try o charge an iPad.

J
Click to expand...

Despite what your ipad is telling your (i.e. not charging), a 1A USB socket will provide charge provided it is in 'standby' mode although it does so at a rather pedestrian pace!
 
Be aware some devices need 2.1A and also have special voltage requirements on the data pins.
Some USB plugs will only supply 1A, or even 0.5A

Unless you are sure of needs its worth installing these higher power chargers especially for items that are perminant fixtures. They will still charge the lower powered devices.
 
Bosun Higgs said:
... they all use the same mini usb plug and socket but does that mean they can all use the same charger outputting a standard voltage. Related to that, where is the mechanism that controls charge level and switches the charger off - in the gadget itself or in the charger plug ( mains or ciggy lighter socket)
Click to expand...
There are several standards for power over USB and for charging. They developed over time as higher-powered devices were developed, and they're supposed to be backwards-compatible. WikiPedia has a good summary. Essentially the power provider (hub or charger) should control how much power (current) it will provide and the device should control what it does with that power.

Not all chargers implement the standards correctly - or at all!

I've used several 12v plug-in chargers over the years; some of them got quite hot. I recently bought one with 2 sockets - one is 2.1A and the other 1A. It came from ebay/Hong Kong. Either will charge this tablet, but one is quicker.
 
USB charging is a nightmare from the specification point of view. At first connection, any device should draw 100mA until it has determined what it is connected to. This is decided by what is connected to the two data pins. In a normal USB charger, a resistor network will tell the device how much current is available, as defined by the USB charging spec. The charging intelligence is in the device.

Computers and hubs are more complex and even have software charging negotiations (thanks Apple).
Depending on how cheap the hub or computer, the over-current protection and USB power may operate on individual or all ports together. We went through the process of working all this out for the USB sockets in our cars - there are some nasty devices out there that just do their own thing. iPhones will stop charging if the voltage drops below 4,6v and only start again if unplugged and re-inserted.

Get the charger that supplies the most current, devices will charge quicker. We've found Kindle, iDevices and most mainstream phones and tablets to be pretty well behaved.
 
Agree with much that has been mentioned.

I am running out of redundancy money and not selling much, so I offer at cost in order to gain a reputation anything on my website. Hopefully it will be a good reputation:) A few more months and I will have to go overseas to earn my crust doing security most likely.

E.g. the usb charger on my website that has on /off switches (looks like I priced it a little too highly) and a usb port. It is nice though and has attractive and useful lighting.

Plus this rather EXCELLENT piece of kit that I intend to attach to a cigar plug and supply with various outlets, e.g. USB being one of them. It is also very good for LEDs. Video here:

http://youtu.be/SAk-NsutM_U

I intend to make the 'ultimate' distribution panel that will do what all the usual ones do, but also allow devices that you have mentioned to be plugged in and charged and various extension cables to be used. A lot of digital meters to indicate what is going on. Safety features built in properly.

Yes most usb outlets give 5V. The device (mobile phone etc) usually has the important circuitry to stop the lithium ion battery from overcharging and exploding. What you stick into the 3 pin 240V 50hz outlet at home is usually just the transformer. If you ever take a laptop battery apart you will find not only the cells but a protective circuit board in there to stop overcharging.
Hope that helps.
 
We found it easier to use inverter, a 220v extension lead with multiple plugs and just use the same chargers we used at home.

The picky on this forum will tell you that not the most effective use of power, but it beats fiddling around with mains and 12v chargers for each item, and we had loads of artery capacity anyway.
 
While there is a standard USB spec it is certainly true that some chargers deliver more than others. I bought a few of these from eBay and with my phone running a satnav (road directions) program they struggle to supply the load, let alone charge the battery.

$(KGrHqEOKjUE3)w8R)59BOH06dT1j!~~_12.JPG
 
Aldi were doing one on Mon . 3 x 12v dc sockets and 2 usb charging sockets. Only rated at 5 amps max but it seems very good quality. £3.99
 
USB charging

View attachment 31808Bought the Blue Sea socket, (as in l'escargot post) and installed it a couple of days ago. I decided to leave off the rectangular trim/cover plate as I could not see that it does anything. It is wired with a 1A fuse to a bus bar, so the little green led is on permanently. The position was chosen because the items being charged (mostly hers) will be on the shelf behind the cushion back and thus should not end up on the deck in bouncy weather.:)

Cheers,

Michael.
 
I'm going to try a bog standard 7 port USB hub to a cigarette lighter socket usb adapter. Soon find out if it works.
 
I don't know whether the figure of 2.1A is significant. My iPad charger supplies 2.1A. My Nexus charger is 2A. My Kindle charger is 0.85A. All will charge the iPad - though the Kindle one takes longer.

2.1A may be the highest current the iPad will take, I suppose. I don't have a more powerful one to try.
 
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