ADVrider

Go Back   ADVrider > Gear > Equipment
User Name
Password
Register Inmates Photos Site Rules Search Today's Posts Mark Forums Read

Reply
 
Thread Tools Search this Thread Display Modes
Old 05-23-2012, 06:37 AM   #1576
JRWooden
Beastly Adventurer
 
Joined: Jul 2008
Location: The great state of confusion
Oddometer: 4,118
Using the Garmin 12V --> 5V brick to charge the SMH10?

I use one of these to power my Garmin Nuvi 500.

http://www.amazon.com/Garmin-010-111.../dp/B001CX4INE

It's wired to un-switched power so I was thinking that when I stop for lunch I could plug the Sena in to that adapter,
(using a mini--> micro USB adapter I have) and give it a bit of a boost charge while I eat.
I think garmin does some funny stuff with the USB cable to let the GPS know that it is not connected to a computer ...

So I'm wondering if this a good idea or not...........
Has anybody tried it?
JRWooden is offline   Reply With Quote
Old 05-23-2012, 06:45 AM   #1577
Pete O Static
Adventure Seeker
 
Pete O Static's Avatar
 
Joined: Apr 2009
Location: The Great White North
Oddometer: 572
Quote:
Originally Posted by JRWooden View Post
I use one of these to power my Garmin Nuvi 500.

http://www.amazon.com/Garmin-010-111.../dp/B001CX4INE

It's wired to un-switched power so I was thinking that when I stop for lunch I could plug the Sena in to that adapter,
(using a mini--> micro USB adapter I have) and give it a bit of a boost charge while I eat.
I think garmin does some funny stuff with the USB cable to let the GPS know that it is not connected to a computer ...

So I'm wondering if this a good idea or not...........
Has anybody tried it?

If you are going to use a different charger, I would check the specs first. Most USB chargers are 5VDC but where they differ is in the amperage rate. If your Sena charger is charging at a rate of 800 milliamperes for instance and you use a charger which charges at 1200 milliamperes, well lithium batteries don't like that.

I do consolidate my chargers down to one or two but always check the specs. It is ok to charge at a slower rate ( using a charger which charges at a lower amperage than required but never higher ) and that of course, is assuming the voltage matches.
__________________
"The trouble with quotes on the Internet is that you don't really know if they are accurate" - Thomas Edison-
Pete O Static is offline   Reply With Quote
Old 05-23-2012, 06:57 AM   #1578
danham
Gnarly Adventurer
 
danham's Avatar
 
Joined: Jul 2009
Location: Cape Cod, MA
Oddometer: 268
Pete is right on. But you're in luck:

Sena 110v charger puts out 5v DC at 1 amp. Garmin 110v chargers put out 5v DC at one amp max. Good to go, because even if you don't have the 12v charger specs, the 110v ones indicate the max.

The funny stuff Garmin does with one of its USB pins will not affect the charging operation.

-dan
__________________
2009 BMW F800 ST
Never let your motorcycle take you where your brain hasn't been five seconds earlier.
danham is offline   Reply With Quote
Old 05-23-2012, 07:13 AM   #1579
JRWooden
Beastly Adventurer
 
Joined: Jul 2008
Location: The great state of confusion
Oddometer: 4,118
Thanks gents!
That was almost too easy ...

I just tried it and it works fine!
JRWooden is offline   Reply With Quote
Old 05-23-2012, 07:48 AM   #1580
mpenner
Heavy Cruiser
 
mpenner's Avatar
 
Joined: Dec 2008
Location: Centerburg, OH
Oddometer: 795
Quote:
Originally Posted by Pete O Static View Post
If you are going to use a different charger, I would check the specs first. Most USB chargers are 5VDC but where they differ is in the amperage rate. If your Sena charger is charging at a rate of 800 milliamperes for instance and you use a charger which charges at 1200 milliamperes, well lithium batteries don't like that.
This would be true if the +5 Vdc were being used to directly charge the battery, but it is not. There is a charging circuit built into devices that use a USB plug to charge a Lithium Ion battery that converts the power from the USB input into the proper voltage and current to charge the battery. As long as the voltage from the USB charger is correct, the charger can not force the charging circuit to accept a higher current than what is needed to charge the battery.

The current rating on the charger is a maximum rating. It will supply less current than this rating if that is what is needed by the charging circuit. If you are skeptical of this, use a current meter to measure the current from the charger as your device is being charged.

I would not hesitate to plug a device that came with a 800 mA USB charger into a 1200 mA charger for the same reasons that I would not hesitate to connect my Battery Tender (which supplies approximately 13.5 Vdc @ 700 mA) into a 20A 110 Vac outlet. Just because the outlet can supply 20A does not mean that it can force the Battery Tender to charge the battery at a 20A rate.
__________________
Mike

2001 KLR 650
2003 V-Strom DL1000
mpenner is offline   Reply With Quote
Old 05-23-2012, 08:37 AM   #1581
danham
Gnarly Adventurer
 
danham's Avatar
 
Joined: Jul 2009
Location: Cape Cod, MA
Oddometer: 268
@mpenner,

You are placing a lot more faith in the internal charging circuits of various consumer electronics devices than I would.

I notice, for example, that Apple now makes two basic chargers, one for iPads and another, less powerful one for the rest of the iOS devices. I haven't measured current at the pins, but I know heat when I feel it and heat is not what li-ion batteries like to experience.

Sure, it will work, but how many times before battery service life is degraded?

To explore your Battery Tender metaphor a bit further, you wouldn't put an automotive 50-amp charger on your bike battery. The output is much more relevant than the input in that example.

-dan
__________________
2009 BMW F800 ST
Never let your motorcycle take you where your brain hasn't been five seconds earlier.
danham is offline   Reply With Quote
Old 05-23-2012, 09:37 AM   #1582
Pete O Static
Adventure Seeker
 
Pete O Static's Avatar
 
Joined: Apr 2009
Location: The Great White North
Oddometer: 572
There ya go, I was not aware of this circuit board. I only know that unless a lithium battery is designed to accept more than 1C charge, the charge rate should never exceed 1C.

1C meaning that if the battery has a 400 ma capacity, it should not be charged at more than 1 X capacity or a charge rate of 400 ma.

Danhams iPad vs iPhone is a good example. The iPad battery has a larger capacity that the iPhone and therefore, can accept a higher charge rate.

Many modern lithium chargers can automatically detect this, it would seem, based on mpenners post, that a USB charger is also capable.

Good info

Cheers
__________________
"The trouble with quotes on the Internet is that you don't really know if they are accurate" - Thomas Edison-
Pete O Static is offline   Reply With Quote
Old 05-23-2012, 10:04 AM   #1583
TowPro
Healing time Sucks
 
TowPro's Avatar
 
Joined: Aug 2009
Location: Compass PA
Oddometer: 2,756
When you plug your Sean into the USB port on your computer you are charging it with the following current:

http://en.wikipedia.org/wiki/Universal_Serial_Bus

USB 2:
Battery Charging Specification 1.1: Released in March 2007 (Updated 15 Apr 2009).
Adds support for dedicated chargers (power supplies with USB connectors), host chargers (USB hosts that can act as chargers) and the No Dead Battery provision which allows devices to temporarily draw 100 mA current after they have been attached. If a USB device is connected to dedicated charger, maximum current drawn by the device may be as high as 1.8 A

USB 3:
Battery Charging Specification 1.2[12]: released in December 2010. Several changes and increasing limits including allowing 1.5A on charging ports for unconfigured devices, allowing High Speed communication while having a current up to 1.5A and allowing a maximum current of 5A.
__________________
2014 R1200GS - My Naked Street Touring Bike
2000 KTM LC4 640 E - For everything else
TowPro is offline   Reply With Quote
Old 05-23-2012, 03:07 PM   #1584
mpenner
Heavy Cruiser
 
mpenner's Avatar
 
Joined: Dec 2008
Location: Centerburg, OH
Oddometer: 795
Talking

Quote:
Originally Posted by danham View Post
@mpenner,

You are placing a lot more faith in the internal charging circuits of various consumer electronics devices than I would.

I notice, for example, that Apple now makes two basic chargers, one for iPads and another, less powerful one for the rest of the iOS devices. I haven't measured current at the pins, but I know heat when I feel it and heat is not what li-ion batteries like to experience.

Sure, it will work, but how many times before battery service life is degraded?

To explore your Battery Tender metaphor a bit further, you wouldn't put an automotive 50-amp charger on your bike battery. The output is much more relevant than the input in that example.

-dan
Quote:
Originally Posted by Pete O Static View Post
There ya go, I was not aware of this circuit board. I only know that unless a lithium battery is designed to accept more than 1C charge, the charge rate should never exceed 1C.

1C meaning that if the battery has a 400 ma capacity, it should not be charged at more than 1 X capacity or a charge rate of 400 ma.

Danhams iPad vs iPhone is a good example. The iPad battery has a larger capacity that the iPhone and therefore, can accept a higher charge rate.

Many modern lithium chargers can automatically detect this, it would seem, based on mpenners post, that a USB charger is also capable.

Good info

Cheers
My understanding is the that the reason that Apple introduced the new charger for the iPad is that chargers for older devices did not supply enough current to charge the iPad at the fastest safe rate (1C as mentioned by Pete). I have an iPod charging on an iPad charging cord at this very moment and it will not harm the iPod battery in any way.

I agree that the output is much more relevant than the input. What I am arguing is that the charging cord is the input and that the charging circuit internal to the device that actually supplies power to the battery is the output.

The charging rate (current) is set by the charging circuit contained in the device and not the USB charging cord.

I have not reverse engineered the Sena unit, but I am pretty certain that it contains a circuit similar to the following:

http://cds.linear.com/docs/Design%20Note/dn250f.pdf

Of course, if a device applies the +5 Vdc from the USB charging cord directly to the battery as the charging voltage then your concerns are well founded, but +5Vdc is going to ruin a battery anyways since Li-Ion batteries require a 4.2 Vdc final charging voltage.

http://www.analog.com/library/analog...1-2/liion.html

There is no way Sena is going to use a USB input as the charging input without an internal charging circuit and then offer a 1 year warranty. I also don't think that it takes a lot of faith to believe that a company like Sena that can design a BT interface can also design a simple charging circuit.

OK I will shut up now and go back to designing the circuits that I am being paid to design
__________________
Mike

2001 KLR 650
2003 V-Strom DL1000
mpenner is offline   Reply With Quote
Old 05-23-2012, 03:24 PM   #1585
danham
Gnarly Adventurer
 
danham's Avatar
 
Joined: Jul 2009
Location: Cape Cod, MA
Oddometer: 268
@Mike:

Hey, I'll always defer to superior training and knowledge. And thank the bearer thereof for helping me learn something. Thanks.

But I hope you'll forgive me if I continue to worry that not all manufacturers are always going to do the right thing with their circuit design, are going to lsiten to their engineers and spend extra money when necessary to protect full battery service life, are going to put the consumer's interest ahead of short term profits.

So far my dealings with Sena suggest they are reputable. But I still go read the labels carefully before trying to charge any of my li-ion-powered devices with chargers other than the one that came with.

-dan
__________________
2009 BMW F800 ST
Never let your motorcycle take you where your brain hasn't been five seconds earlier.
danham is offline   Reply With Quote
Old 05-23-2012, 04:03 PM   #1586
danham
Gnarly Adventurer
 
danham's Avatar
 
Joined: Jul 2009
Location: Cape Cod, MA
Oddometer: 268
Mike,

Thought you might be interested in this blog, which describes a teardown of an Apple iPhone charger and, about a third of the way down the page, links to differences between this very sophisticated charger and a cheap knockoff, which the author says is downright dangerous in its design. Great example both of good design and the kind of cheap shortcuts I worry about [grin].

http://www.arcfn.com/2012/05/apple-i...n-quality.html

-dan
__________________
2009 BMW F800 ST
Never let your motorcycle take you where your brain hasn't been five seconds earlier.
danham is offline   Reply With Quote
Old 05-23-2012, 05:17 PM   #1587
Pete O Static
Adventure Seeker
 
Pete O Static's Avatar
 
Joined: Apr 2009
Location: The Great White North
Oddometer: 572
Interestingly, I have a cigarette lighter adapter with a USB port and while it will charge various things, my iPhone simply will not charge from it. Attach the iPhone to an identical looking unit from a known brand like Belkin and it will charge, happy as a clam.

The Sena comes with a 12vdc cigarette adapter but I have thought of using the USB cord from the wall charger and sharing the same Belkin charger I use for the phone. One less cord to carry on the road. I hadn't got around to checking the specs.

So if I understand mpenner correctly, if the Belkin unit is capable of delivering 1200ma but the Sena only requires 600ma, the charger will only deliver what is needed ie 1C not 2C?
__________________
"The trouble with quotes on the Internet is that you don't really know if they are accurate" - Thomas Edison-
Pete O Static is offline   Reply With Quote
Old 05-23-2012, 07:51 PM   #1588
mpenner
Heavy Cruiser
 
mpenner's Avatar
 
Joined: Dec 2008
Location: Centerburg, OH
Oddometer: 795
Quote:
Originally Posted by danham View Post
But I hope you'll forgive me if I continue to worry that not all manufacturers are always going to do the right thing with their circuit design, are going to lsiten to their engineers and spend extra money when necessary to protect full battery service life, are going to put the consumer's interest ahead of short term profits.

So far my dealings with Sena suggest they are reputable. But I still go read the labels carefully before trying to charge any of my li-ion-powered devices with chargers other than the one that came with.

-dan
I completely agree that the absolute safest choice is to use only the charging cord that came with the unit, but even then there is always the possibility that even that charging cord will fail and damage the battery or charging circuit due to manufacturing defects or poor design.

Quote:
Originally Posted by danham View Post
Mike,

Thought you might be interested in this blog, which describes a teardown of an Apple iPhone charger and, about a third of the way down the page, links to differences between this very sophisticated charger and a cheap knockoff, which the author says is downright dangerous in its design. Great example both of good design and the kind of cheap shortcuts I worry about [grin].

http://www.arcfn.com/2012/05/apple-i...n-quality.html

-dan
Thanks for the link. There certainly are differences in quality of design and manufacture between the various suppliers. I always enjoy examining other's designs and Apple generally seems to get things right. Unfortunately the documentation that is supplied with consumer equipment is rarely enough to determine whether or not it is quality equipment. Often you have to rely on the reputation of the supplier.

Some of the best power supply designs can be found in avionics equipment since peoples lives depend on them working correctly under all sorts of conditions. These designs are tortured and tested in ways that Apple has probably never even dreamed of and the results are documented in a very large stack of paper.

Quote:
Originally Posted by Pete O Static View Post
Interestingly, I have a cigarette lighter adapter with a USB port and while it will charge various things, my iPhone simply will not charge from it. Attach the iPhone to an identical looking unit from a known brand like Belkin and it will charge, happy as a clam.

The Sena comes with a 12vdc cigarette adapter but I have thought of using the USB cord from the wall charger and sharing the same Belkin charger I use for the phone. One less cord to carry on the road. I hadn't got around to checking the specs.

So if I understand mpenner correctly, if the Belkin unit is capable of delivering 1200ma but the Sena only requires 600ma, the charger will only deliver what is needed ie 1C not 2C?
That is exactly what I am suggesting and that is what I do. I use a USB cigarette lighter adapter with the charging cord from my phone to charge the Sena.

Phones often play tricks with the voltages on the D+ and D- lines on the USB connector so that they will only work with their chargers and I am sure that that is why your "generic" USB cig adapter will not work with the iPhone. The more expensive Belkin is emulating Apples tricks on the other USB lines, so it works just fine. In my case, my phone will not work with the Sena charging cord, but the Sena will charge with the phone cord so I take the phone cord.

Try this experiment. Charge your fully discharged Sena unit with the Sena supplied charging adapter and cord and measure how long it takes. It will take about 8 hours (the Sena does not charge at anywhere near a 1C rate or it would take only 1 hour). Then discharge your Sena unit again and charge it with the Belkin adapter. The amount of time that it takes to charge the Sena will be very close in both cases indicating that the charge rate is the same.

Or try this thought experiment. According the danham (I have not verified this, but I am sure that he is correct), the Sena charging cord supplies a maximum of 1A. I know from charging the Sena units many times that it takes about 8 hours to fully charge a completely discharged unit. If the Sena were consuming the full amount of current available from the charging cord for the 8 hours that they were being charged, they would have to have an 8 Ah battery (1A x 8 hours) which is equivalent to 8000 mAh. If Sena knew how to make a 8000 mAh battery would fit into these units, we would all be driving electric cars. Therefore, the Sena supplied charging cord has a much higher maximum current rating than what is needed for the units.

In summary, I contend that while there are differences in quality between different charging cords (and there is some risk in using poor quality charging cords), there is no danger in using a high quality charging cord with a different maximum current rating than the one that was supplied with the equipment if the charging input is a USB connector and the battery being charged is a Li-Ion battery. If you use a charging cord with a lower maximum current rating, it may take longer to charge the unit (or worst case, it will not charge the unit, but won't damage it.) If you use a charging cord with a higher maximum current rating, the charging circuit in the unit will only use the amount of current that is needed to correctly charge the battery.
__________________
Mike

2001 KLR 650
2003 V-Strom DL1000

mpenner screwed with this post 05-23-2012 at 08:04 PM
mpenner is offline   Reply With Quote
Old 05-25-2012, 01:05 PM   #1589
firebrick
Studly Adventurer
 
Joined: Oct 2009
Location: Iowa
Oddometer: 884
I see revzilla has sena marked down 25% so Im getting ready to pull the trigger on the dual set of smh-10 and ear bud adapters. Ive never had an intercom before. Will be using with iPhones and nolan n43 and nolan 102 helmets. Im ordering tonight so would just like to make sure there is nothing else I will need to get me up and running. Thanks. I looked at the rocketmoto? site but it looks like revzilla is cheaper right now. Are the intercoms a different version?
__________________
2009 buddy 125
2006 tw200
firebrick is offline   Reply With Quote
Old 05-25-2012, 01:25 PM   #1590
Rdub
Adventurer
 
Joined: Nov 2010
Location: San Antonio, Tx
Oddometer: 13
firebrick - did you check with rocketmoto to see if they were still offering the advrider discount? If not, you may want
to do that. If the discount still stands, it will be cheaper than Revzilla. I just got my dual smh10's a couple of weeks ago.
They are the latest version that are firmware upgradable.
__________________
2012 Vstrom 650
Rdub is offline   Reply With Quote
Reply

Share

Thread Tools Search this Thread
Search this Thread:

.
Display Modes

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 On

Forum Jump


Times are GMT -7.   It's 10:11 PM.


Powered by vBulletin® Version 3.8.5
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Copyright ADVrider 2011-2014