Cruisers Forum
 


Join CruisersForum Today

Reply
 
Thread Tools Rate Thread Display Modes
Old 14-10-2015, 07:56   #1
RDW
Registered User

Join Date: Dec 2009
Location: Lexington, Kentucky
Boat: Morris 1996 46' Lexington
Posts: 378
Solar Charging

I have solar panels on my boat. If I were to get into a bad situation where I lost my boat electrical system like my batteries blowing up etc., could I hook my solar panel directly to cell phones, computers and Ipad type devices so I could use them to navigate.
I know this is off the wall question but it is an interesting concept.
RDW
__________________

__________________
RDW is offline   Reply With Quote
Old 14-10-2015, 08:02   #2
Registered User
 
zboss's Avatar

Join Date: Sep 2011
Location: On a boat
Boat: Cabo Rico 38
Posts: 3,426
Re: solar charging

No, those devices use a lower voltage than the panels provide. You would have to use a converter to convert the voltages down to whatever you needed.

So... generally Panels>Charge Controller Load output>Inverter>Device Plug>Device.
__________________

__________________
zboss is offline   Reply With Quote
Old 14-10-2015, 08:26   #3
RDW
Registered User

Join Date: Dec 2009
Location: Lexington, Kentucky
Boat: Morris 1996 46' Lexington
Posts: 378
Re: solar charging

This is a quick reply to my own post Somewhere I saw a you tube video of a guy showing how to use a lead pencil to act as a resister which lowered the voltage from a 12 volt battery to charge a cell phone.
rdw
__________________
RDW is offline   Reply With Quote
Old 14-10-2015, 09:46   #4
Senior Cruiser

Cruisers Forum Supporter

Join Date: Aug 2009
Location: between the devil and the deep blue sea
Boat: a sailing boat
Posts: 17,314
Re: solar charging

The solars output voltage that would fry your chargers. You want as a minimum a solar panel regulator with "appliances" output. Then any car plug charger will charge many of your 5V (mostly USB) devices.

If the regulator kicks the bucket but you have any sound battery, you can put the panels directly onto the battery and feed the chargers of the battery. In emergency, a half dead battery can be used this way too. (E.g. one with a shot cell). Mind in this scenario you MUST control the temperature of the battery (by e.g. touching its sides every 30 minutes or so). And do not leave the panel connected once you have done your charging.

Etc.

Cheers,
b.
__________________
barnakiel is offline   Reply With Quote
Old 14-10-2015, 09:51   #5
Senior Cruiser

Cruisers Forum Supporter

Join Date: Aug 2009
Location: between the devil and the deep blue sea
Boat: a sailing boat
Posts: 17,314
Re: solar charging

Solar > regulator with appliance out > cigarette plug adapter (12V/5V USB devices like phones and tablets).

generic style: http://sunsoltechk.com/images/solar_...ontroller1.jpg

Or else Solar > battery > etc.

b.
__________________
barnakiel is offline   Reply With Quote
Old 14-10-2015, 09:59   #6
Registered User
 
Privilege's Avatar

Join Date: Oct 2009
Location: Bermuda
Boat: Privilege 435
Posts: 362
Images: 12
Re: solar charging

Quote:
Originally Posted by zboss View Post
So... generally Panels>Charge Controller Load output>Inverter>Device Plug>Device.
The iPhones and iPads charge on DC at 5V. Converting it to AC and then back to DC via a inverter makes no sense. The white plugs that come with the apple products are not technically chargers but are voltage regulators which take the voltage down to 5V. It's the same with the plug-in 12v car adapters. The devices have another internal regulator which will only allow the phone to charge at a set voltage and amperage, that's why you can use a 2.1amp iPad charger to charge an 1amp iPhone.


Therefore, any device plugged into a power supply at or anywhere near 12v will work. If your solar panels are putting out, say 18v, I wonder if the adapters will handle that much current, I suspect that they will.
__________________
Privilege is online now   Reply With Quote
Old 14-10-2015, 12:18   #7
RDW
Registered User

Join Date: Dec 2009
Location: Lexington, Kentucky
Boat: Morris 1996 46' Lexington
Posts: 378
Re: solar charging

The white plugs that come with the apple products are not technically chargers but are voltage regulators which take the voltage down to 5V. QUOTE
The white plugs convert AC to DC and then to 5 volt, 2, or 2.4 volt,,,,,,, I think.
rdw
__________________
RDW is offline   Reply With Quote
Old 14-10-2015, 12:25   #8
RDW
Registered User

Join Date: Dec 2009
Location: Lexington, Kentucky
Boat: Morris 1996 46' Lexington
Posts: 378
Re: solar charging

I should have thought a little more before I posted the question.
I would already have a USB outlet that was coming off 12 DC on the boat for usual charging in a normal system. I would bet I could hook that 12 DC outlet directly to the solar panel and it would work but I do not know. If the volts were too much and I had a multimeter, I bet I could shade enough panel to get near the right volts.
Sorry if I sound a little crazy. A little knowledge is dangerous.
rdw
__________________
RDW is offline   Reply With Quote
Old 14-10-2015, 12:36   #9
Moderator
 
a64pilot's Avatar

Cruisers Forum Supporter

Join Date: Oct 2013
Location: Albany Ga.
Boat: Island Packet 38
Posts: 17,045
Re: solar charging

Quote:
Originally Posted by Privilege View Post

Therefore, any device plugged into a power supply at or anywhere near 12v will work. If your solar panels are putting out, say 18v, I wonder if the adapters will handle that much current, I suspect that they will.
Most all of those little cigarette lighter USB things will work in an airplane with a 28V system, or all I have tried did, many state operating voltage on them.
__________________
a64pilot is offline   Reply With Quote
Old 14-10-2015, 13:07   #10
֍֎֍֎֍֎֍֎֍֎

Cruisers Forum Supporter

Join Date: Apr 2006
Posts: 13,037
Re: solar charging

Learn to use the sun and stars, and you will have enough information to navigate to a shore. From there you can always follow the shore.


Now you don't have to worry about the batteries blowing up, the multimeter falling overboard, the iPhone and the iPad being destroyed by a solar flare, and all the rest of that electronic stuff.


And if you have, or can imagine in your mind, an ANALOGUE WATCH? That makes a pretty good compass, too. See para.1, it will be covered with that stuff.
__________________
hellosailor is offline   Reply With Quote
Old 14-10-2015, 13:48   #11
Registered User
 
travellerw's Avatar

Join Date: Jan 2014
Location: Martinique
Boat: Fortuna Island Spirit 40
Posts: 1,721
Re: Solar Charging

I have hooked a 12V usb charger directly to a solar panel. It works fine as long as the panel has good sunlight.

I also bought one of these as my backup of my backup. It charges my tablet in 4 hours of direct sunlight. Its also small enough to throw in a ditch bag.



AnkerĀ® 14W Solar Panel Foldable Dual-port Solar Charger with PowerIQ™ Technology for 5V USB-charged Devices Including GPS Units, iPhone 6 5S 5C 5 4S, iPad 5 4 3 2, Air, mini, Android Phones and Android Tablets: Amazon.ca: Cell Phones & Access
__________________
travellerw is online now   Reply With Quote
Old 14-10-2015, 16:03   #12
֍֎֍֎֍֎֍֎֍֎

Cruisers Forum Supporter

Join Date: Apr 2006
Posts: 13,037
Re: Solar Charging

Bear in mind, if you hook a "12v" charging adapter directly to a solar panel, that pnel may have a 17-22v unregulated output, and the "12v" devices are not designed to run at that voltage. Some are made with components rated at 15V, the next standard voltage rating for components in 12V use, and above the 14.4 volts "maximum" in 12 volt nominal systems.


So you may be more or less lucky, depending on just how well the costs were cut.
__________________
hellosailor is offline   Reply With Quote
Old 14-10-2015, 16:30   #13
Registered User
 
travellerw's Avatar

Join Date: Jan 2014
Location: Martinique
Boat: Fortuna Island Spirit 40
Posts: 1,721
Re: Solar Charging

Quote:
Originally Posted by hellosailor View Post
Bear in mind, if you hook a "12v" charging adapter directly to a solar panel, that pnel may have a 17-22v unregulated output, and the "12v" devices are not designed to run at that voltage. Some are made with components rated at 15V, the next standard voltage rating for components in 12V use, and above the 14.4 volts "maximum" in 12 volt nominal systems.


So you may be more or less lucky, depending on just how well the costs were cut.
"Most" 12V electronics are made with 25V rated components.. I use "most" in quotes cause you never know what it is until you take it apart.

If you really wanted to be safe, you could build a resistor dividor network.. 70Kohm and 130Kohm should keep the voltage at a safe level (around 13V).. Total cost, under a penny!
__________________
travellerw is online now   Reply With Quote
Old 14-10-2015, 17:39   #14
Senior Cruiser

Cruisers Forum Supporter

Join Date: Jul 2006
Location: Chesapeake Region and Maine
Boat: 42' Bob Perry sloop
Posts: 4,038
Images: 4
Re: Solar Charging

RDW,

Let me get this straight: you have a Morris 46 and you say things like, "If the volts were too much and I had a multimeter, I bet I could shade enough panel to get near the right volts. Sorry if I sound a little crazy. A little knowledge is dangerous."

Yes, it is a little crazy.

May I humbly suggest that the first thing you need to do is gain a very elementary understanding of things electrical on your boat? I'd suggest you start with a good basic text, like Charlie Wing's book.

As for "..if I had a multimeter" ..... if you don't have one already and have basic knowledge about how to use it, you really need to correct this fast. A decent multimeter and, IMHO, a clamp-on AC/DC ammeter are very basic tools needed for maintenance and troubleshooting on any cruising boat.

Bill
__________________
btrayfors is offline   Reply With Quote
Old 14-10-2015, 19:06   #15
֍֎֍֎֍֎֍֎֍֎

Cruisers Forum Supporter

Join Date: Apr 2006
Posts: 13,037
Re: Solar Charging

traveler-
They SHOULD be using 25v rated components, that would be what a good engineer would normally choose. However, you know ICOM, the radio company? They lost a lot of ICOM 706-series fans because the main caps across the power input, which are always connected, were 15V rated parts.
And now that so much stuff, especially the cheap DC-to-DC power supplies, is coming from "cheapest shop in Shenzhen! Promising You!" I expect that even more parts will be spec'd at 15V for "12" volt use. Saturn car owners had a series of ECU failures because of poor quality electrolytics. The computer industry lost a lot of motherboards that way...what was it, 15 or 20 years ago?
When I see a "12v USB adapter" on sale for less money than it would cost me to post it to the source of origin....I have to ask, how can they sell it so cheap? Kinda like the problem with counterfeit and no-name lithium batteries for call phones and other gizmos catching fire, because so many companies cheated on their specs.
Mind you, I LIKE fire. I just don't appreciate it coming as a surprise.
__________________

__________________
hellosailor is offline   Reply With Quote
Reply

Tags
charging, solar

Thread Tools
Display Modes Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Solar Panel wiring/charging options IslandHops Electrical: Batteries, Generators & Solar 5 17-02-2009 03:29
Charging 48v battery bank with solar panels Hankthelank Electrical: Batteries, Generators & Solar 3 05-10-2008 14:55
Winter Layup Solar Charging Sandero Electrical: Batteries, Generators & Solar 8 22-10-2007 09:36
Outboard engine and solar power charging THamel Construction, Maintenance & Refit 2 19-05-2003 23:28



Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -7. The time now is 08:39.


Google+
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.
Social Knowledge Networks
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.

ShowCase vBulletin Plugins by Drive Thru Online, Inc.