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Old 06-25-14, 05:30 PM   #1
antimonysarah
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Garmin Edge Touring + charging while riding: anyone have any luck?

I got a Garmin Edge Touring Plus for Christmas, and I have never successfully gotten it to charge from an external battery pack for very long -- it keeps trying to auto power down randomly. I returned it and got a new one -- same problem. Has anyone gotten this combo to work? Any recommendations?
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Old 06-25-14, 06:33 PM   #2
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This reply may be of no use whatsoever so be forewarned.
I don't own a garmin touring +, but I do have an edge 705 and an edge 200.
I sucessfully charge both of these as i'm using both units with the gomadic battery pack
(uses 4 AA batteries). the gomadic also comes with a USB cable designed for charging and not for transfering data.
This could be the crux of your problem. If you use a data cable on the 705 or the 200 strange, non-charging things happen...like random power downs.
The same could be true of the Touring +.
OTOH, each Garmin seems to be designed to provide a unique user experience, so this may not help you at all.
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Old 06-25-14, 06:38 PM   #3
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This reply may be of no use whatsoever so be forewarned.
I don't own a garmin touring +, but I do have an edge 705 and an edge 200.
I sucessfully charge both of these as i'm using both units with the gomadic battery pack
(uses 4 AA batteries). the gomadic also comes with a USB cable designed for charging and not for transfering data.
This could be the crux of your problem. If you use a data cable on the 705 or the 200 strange, non-charging things happen...like random power downs.
The same could be true of the Touring +.
OTOH, each Garmin seems to be designed to provide a unique user experience, so this may not help you at all.
It's a Gomadic I'm using, with the correct cable (at least according to Gomadic), alas.
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Old 06-26-14, 03:50 AM   #4
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Ah! So this may be part of the touring + " unique user experience".

One more suggestion, try it without the internal battery being fully charged.
And boot everything up in this order: 1 connect the garmin and gomadic. 2 make sure both units are off.
3 turn on the gomadic. 4 wait for the gomadic to boot up the garmin.
I think this allows the power to be drawn from the gomadic first.
At least it works for me.
But..." Unique user experience ".

Hope. This helps.
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Old 06-26-14, 05:29 AM   #5
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Not that I have any "first hand experience" charging a Garmin while using it but if I did I would think it better to use a standard "Cell phone type" Li-ion external battery/ USB charger. I say this because 4-AA's in series are only 6volts at best. Since a USB port needs 5 volts to operate I would think having an 8.4 volt ( peak ) Li-ion battery source ( 2 cell in series )... ( vs. the 6 volt AA's ) would be the better way to go.
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Old 06-26-14, 06:43 AM   #6
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I think the Gomadic must have a boost stage in its regulator or else it wouldn't work as well as it does. You can use it just fine with rechargeable batteries, for example. Same with the "lipstick" liion packs with one cell, they are boosting the voltage so they can regulate it to 5v. I have a gomadic, but the lipstick packs are a lot more convenient

I have been very successful at charging my 800 while navigating. Unfortunately, that doesn't necessarily mean anything with regards to the touring model. Apparently not every design team at Garmin realizes being able to charge while navigating is a good thing, the 500 causes a lot of people problems with this.
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Old 06-26-14, 08:33 AM   #7
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I think the Gomadic must have a boost stage in its regulator or else it wouldn't work as well as it does. You can use it just fine with rechargeable batteries, for example. Same with the "lipstick" liion packs with one cell, they are boosting the voltage so they can regulate it to 5v. I have a gomadic, but the lipstick packs are a lot more convenient

I have been very successful at charging my 800 while navigating. Unfortunately, that doesn't necessarily mean anything with regards to the touring model. Apparently not every design team at Garmin realizes being able to charge while navigating is a good thing, the 500 causes a lot of people problems with this.
Yeah, I think the second one's going to go back after the 400K this weekend. I'll do what I did on the 300k -- run it down until it freaks out, then navigate the old fashioned way with it off and recharging from the battery pack until it gets dark, and then turn on the GPS and it should at least get me back to roads I'm familiar with if not all the way to the end on its internal battery. And since unfortunately REI doesn't seem to have the 800 any more (the Touring was a gift, so it's much easier to stick with the same store than try to buy an 800 elsewhere), I guess I'm going to have to spring for an 810, despite not having a smartphone and thus not having any use for it's fancier features.

It may well be a voltage thing -- it seems to do OK for a few hours with the Gomadic, but once it starts freaking out, it won't stop (with that set of batteries).
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Old 06-27-14, 04:20 AM   #8
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Yeah, I think the second one's going to go back after the 400K this weekend. I'll do what I did on the 300k -- run it down until it freaks out, then navigate the old fashioned way with it off and recharging from the battery pack until it gets dark, and then turn on the GPS and it should at least get me back to roads I'm familiar with if not all the way to the end on its internal battery. And since unfortunately REI doesn't seem to have the 800 any more (the Touring was a gift, so it's much easier to stick with the same store than try to buy an 800 elsewhere), I guess I'm going to have to spring for an 810, despite not having a smartphone and thus not having any use for it's fancier features.

It may well be a voltage thing -- it seems to do OK for a few hours with the Gomadic, but once it starts freaking out, it won't stop (with that set of batteries).
Well one advantage of using any device that operates off of AA's is that if you don't carry back-up cells you can usually find a store that sells AA's almost anywhere.

Now if you absolutely have to have GPS on at all times another way to go might be to buy a good 4-cell rechargeable Li-ion battery ( say in the 6200 to 6800mAh range ) and one of these. In combo they should power ( or charge ) almost any USB device for a good long time. I don't know if it would get you through a 300 or 400K ( hooked up to a Garmin ) but if it didn't I would be surprised. If that didn't work you'd be better using a dynamo powered USB charger. The down side on that is that the dynamo set-up is not cheap and the USB charger for those are more expensive as well.
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Old 06-27-14, 04:52 AM   #9
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Garmin Hiking units. I use an on old etrex vista hcx. But, the new ones also run on AA batteries, external power, or a li ion pack. Nice thing about the old etrex is it picks up where it left off when the battery died. Its bigger and heavier, but its navigation functions are rock solid and it NEVER errors out. I don't care about cadence and heart rate so its perfect for me. Worked on a 24 fleche and many brevets.
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Old 06-27-14, 08:12 AM   #10
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Well one advantage of using any device that operates off of AA's is that if you don't carry back-up cells you can usually find a store that sells AA's almost anywhere.

Now if you absolutely have to have GPS on at all times another way to go might be to buy a good 4-cell rechargeable Li-ion battery ( say in the 6200 to 6800mAh range ) and one of these. In combo they should power ( or charge ) almost any USB device for a good long time. I don't know if it would get you through a 300 or 400K ( hooked up to a Garmin ) but if it didn't I would be surprised. If that didn't work you'd be better using a dynamo powered USB charger. The down side on that is that the dynamo set-up is not cheap and the USB charger for those are more expensive as well.
No, I know about those options, and I have a dynamo hub already for my front light. The problem I'm having is that the Edge Touring turns itself off while charging from the battery pack I have, which is AA-based.

I don't have to have a GPS all the time, but I'm faster if I do, especially in the dark.

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Garmin Hiking units. I use an on old etrex vista hcx.
At least one person on the brevets I've done has had one of those, but I'll probably try one of the other cycling ones first just for size/weight (especially when I'm taking it on short rides).
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Old 06-27-14, 10:05 AM   #11
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I am much happier with my 800 now that I know not to display maps. I find the best screen is just the list of turns. I was riding with map display recently and found that it seems to burn through the batteries much faster than either the turn list or the speedometer screen. Which makes sense.
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Old 06-27-14, 12:11 PM   #12
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I am much happier with my 800 now that I know not to display maps. I find the best screen is just the list of turns. I was riding with map display recently and found that it seems to burn through the batteries much faster than either the turn list or the speedometer screen. Which makes sense.
Actually, that's really helpful to know for limping my Touring through the 400k tomorrow -- I was running it 100% on the map screen. I'll switch it to the speedometer screen -- the list of turns I find distracting because it's not identical to the cue sheet and my brain starts trying to treat it like a puzzle rather than concentrating on riding.
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Old 06-27-14, 01:26 PM   #13
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No, I know about those options, and I have a dynamo hub already for my front light. The problem I'm having is that the Edge Touring turns itself off while charging from the battery pack I have, which is AA-based.

I don't have to have a GPS all the time, but I'm faster if I do, especially in the dark.
I understand. Could be that some of the Garmins just aren't designed to use while charging. I was just speculating that perhaps the AA charger would have lapses where the device wouldn't be able to supply enough current to keep the Garmin from bugging out. I've read of people having the same problem with their Iphones ( where an output from a dynamo hub couldn't keep the phone from bugging out of the charge cycle.). Electronic devices can be strange like that when the power source starts to fade.

The advice about switching from the map screen to another screen with less graphics to increase run time ( while running in the background ) is an interesting idea. That might work with other devices as well. I usually use my Android "Cue Sheet " or "Locus" app for navigation. With the Cue sheet app I have the option to just display the cue sheet. Doing that ( coupled with just turning off the screen when not needed ) might increase my run time as well. It makes sense that if the unit is still running a map in the background that it would have to draw a bit more power. Really good tip there that I'm sure to try.
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Old 06-29-14, 08:51 AM   #14
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Followup: the new one is much less flakey -- it will charge from the AA pack in all but one specific situation, where it will shut itself off repeatedly, whereas the old one just seemed random. That situation being when it's already close to 100% charged, which makes sense. And it's consistent about trying to shut the unit down when external power is disconnected (the old one would sometimes allow it and sometimes wouldn't), which means I just have to be ready for it when disconnecting the power.

Successfully navigated me around the 400k with no problems (and no bonus miles). It did seem to draw less on the info page, and I stuck the battery status on that page so I could easily keep track of it.
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Old 06-30-14, 02:22 PM   #15
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Now if you absolutely have to have GPS on at all times another way to go might be to buy a good 4-cell rechargeable Li-ion battery ( say in the 6200 to 6800mAh range ) and one of these. In combo they should power ( or charge ) almost any USB device for a good long time. I don't know if it would get you through a 300 or 400K ( hooked up to a Garmin ) but if it didn't I would be surprised.
Looks like the Garmin Touring has an 1100 mAh battery, and lasts up to 17 hours on that.

If we assume 12 hours on a charge, 50% charging efficiency, and that we start with a full charge on everything, a 5000 mAh 1s battery ought to have enough energy to fully charge it twice, giving you 36 hours. (The way to maximize it would be to leave the charger off until the GPS is nearly dead, then charge until it's nearly full, then turn it off until the GPS is nearly dead again, then repeat ...)

(Note that many of the cheap Chinese chargers greatly exaggerate the size of their batteries.)

For comparison, the stock battery pack on a Magicshine clone is about 4400 mAh 2s, or 8800 mAh if we look at it as a 1s pack.

You could up the 50% efficiency to 100% if you added some connections directly to the GPS's internal battery and put your external 1s battery in parallel with that (probably OK as long as both start at the same level of charge) but there's some gotchas there and I wouldn't suggest that unless you knew what you were doing.

Personally, I'd want to have the GPS on all the time if at all possible, if only to record my ride, as I really like to be able to show on a map where I've ridden.
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Old 07-01-14, 01:10 PM   #16
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I am much happier with my 800 now that I know not to display maps. I find the best screen is just the list of turns. I was riding with map display recently and found that it seems to burn through the batteries much faster than either the turn list or the speedometer screen. Which makes sense.
Maybe that's what caused my 800's battery life to drop from about 15 hours to 8-ish. I recorded an 8-hour ride with maps on for only about an hour, and the battery was down to half. The 400k last month I left the display up, and it was about out of juice after 8 hours. The 800, as you noted, had no problem recharging from a battery pack.
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Old 07-02-14, 10:19 AM   #17
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So I had my first experience with this and I didn't see any mention of the newer models. I did a 300 mile ride with my Garmin 510 and when it was getting low on power I plugged in a li-ion charger. I have no idea how long it should be plugged in for, it was probably a good 10 mins. My Garmin did want to turn off but I stopped it. Eventually my Garmin died about 9 miles from the end (21.5 total hours). Do you think the Garmin even got a charge, I thought 20 hours was their stated limit? Maybe I need to pause the ride and power down before I charge it?
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Old 07-02-14, 02:53 PM   #18
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Just a sanity check here. Are you certain that your auto power down function is set correctly?

The device may be thinking it is inactive and powering down. From the user manual:


Select an option.
Using the Auto Power Down Feature
This feature automatically turns off the device after 15 minutes
of inactivity.

1 Select System Auto Power Down
2 Select On
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Old 07-02-14, 04:05 PM   #19
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So I had my first experience with this and I didn't see any mention of the newer models. I did a 300 mile ride with my Garmin 510 and when it was getting low on power I plugged in a li-ion charger. I have no idea how long it should be plugged in for, it was probably a good 10 mins. My Garmin did want to turn off but I stopped it. Eventually my Garmin died about 9 miles from the end (21.5 total hours). Do you think the Garmin even got a charge, I thought 20 hours was their stated limit? Maybe I need to pause the ride and power down before I charge it?
the problem is that if you wait for the battery to get low, you may actually over-stress the external battery. Most batteries have higher capacities of they are discharged slowly
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Old 07-03-14, 03:40 PM   #20
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I got a Garmin Edge Touring Plus for Christmas, and I have never successfully gotten it to charge from an external battery pack for very long -- it keeps trying to auto power down randomly. I returned it and got a new one -- same problem. Has anyone gotten this combo to work? Any recommendations?
I use a rechargable external batter charger. I've used it multiple times with the 800 without any issues. I've used it a few times with the Touring without any issues.

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Looks like the Garmin Touring has an 1100 mAh battery, and lasts up to 17 hours on that.
If you are using it for navigating (especially), 17 hours is very optimistic (by about a factor of 2).

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If we assume 12 hours on a charge, 50% charging efficiency, and that we start with a full charge on everything, a 5000 mAh 1s battery ought to have enough energy to fully charge it twice, giving you 36 hours.
I bet you could get (almost) 3 charges out of a 5000 mAh battery.

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(The way to maximize it would be to leave the charger off until the GPS is nearly dead, then charge until it's nearly full, then turn it off until the GPS is nearly dead again, then repeat ...)
Based on what, exactly? The device is consuming power as you are charging it. It might be better not to wait until it is "nearly dead" and charge it while the sun is shining (that is, it could be raining when it's "nearly dead" and you might not want to have to charge it then).

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I am much happier with my 800 now that I know not to display maps. I find the best screen is just the list of turns. I was riding with map display recently and found that it seems to burn through the batteries much faster than either the turn list or the speedometer screen. Which makes sense.
This is a bit sad but whatever works for you. I almost always have the map displayed and I have gotten to be able to glance at it to have a sense of what is upcoming.

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the problem is that if you wait for the battery to get low, you may actually over-stress the external battery. Most batteries have higher capacities of they are discharged slowly
???

The 500 has a 600mAh battery. Most chargers that people are likely to use will be at least twice that capacity. I doubt that "over stressing" is a real problem.

Last edited by njkayaker; 07-03-14 at 03:52 PM.
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Old 07-04-14, 01:31 PM   #21
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I use a rechargable external batter charger. I've used it multiple times with the 800 without any issues. I've used it a few times with the Touring without any issues.


If you are using it for navigating (especially), 17 hours is very optimistic (by about a factor of 2).
Yeah. On the map screen, while recording and navigating with tones on and a 15-second backlight timeout, my Touring will definitely do 8 hours, probably 10 if letting it go all the way to zero.

On the info screen, navigating, recording, tones on, backlight 15 seconds, it seems like it'd go more like 13 -- it went close to 11 hours and was down a bit under 20% when I plugged it in on the 400k.

I think the first one I got had something wrong with the battery/charging port -- the second one will keep trying to shut itself off if I try to charge it with a full battery, but is otherwise OK with the external pack. I also switched to lithium batteries, because lighter and slightly higher voltage, which may have helped.
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Old 07-06-14, 12:17 PM   #22
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the problem is that if you wait for the battery to get low, you may actually over-stress the external battery. Most batteries have higher capacities of they are discharged slowly
Over stress?

Most "portable USB chargers" charge at 0.5 to 2.0 amps (2 amps for the bigger ones.) Your GPS probably accepts around 0.5 amps (2.0 amps is more for charging your iPad) and it'll charge at that rate when nearly empty all the way up to when it has 80-90% charge, at which point the charge rate will taper off as it gets close to 100%.

Even if you're charging your iPad at 2.0 amps, these charges generally discharge the battery at less than a 1C rate (a 1C rate = it will only work for an hour, 2C = 30 minutes, 0.5C = 2 hours, etc.), and the battery probably can provide a few times that before it starts to lose more than a minuscule amount of capacity to an excessive discharge rate. And your GPS will accept power a lot slower than the iPad, even if fully discharged.

You will not stress it, unless it's one of those tiny units that's like 1 inch by 1 inch, and then it'll just charge slower rather than let itself be stressed. If you're using one of those chargers that takes a single AA battery (alkaline batteries definitely do work better with low discharge rates), then maybe, but anything better than that ... no.

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Based on what, exactly? The device is consuming power as you are charging it. It might be better not to wait until it is "nearly dead" and charge it while the sun is shining (that is, it could be raining when it's "nearly dead" and you might not want to have to charge it then).
Based on the typical portable charging having that'll output up to one amp or so but they'll still use power even with no load.

So you can charge your GPS at 1/2 amp or so and power the battery light while it's on, or you can continue to charge (just replace power as used) your already full GPS at 0.04 amps ... and power the battery light while it's on.

If you're worried about not being able to charge it when you need to, charge it when it's 40% full, and stop when it's 90% full. My point is ... don't leave it charging all the time, or its own status lights will probably drain more power than the GPS does.
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Old 07-07-14, 09:27 AM   #23
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My point is ... don't leave it charging all the time, or its own status lights will probably drain more power than the GPS does.
I doubt that this is true.
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Old 07-07-14, 12:15 PM   #24
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Cant drain the batteries running it, and charge the battery at the same time.

you could buy a hub dynamo based charging scheme , there are several out theere by now.
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Old 07-07-14, 06:25 PM   #25
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Cant drain the batteries running it, and charge the battery at the same time.
????

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you could buy a hub dynamo based charging scheme , there are several out theere by now.
Dynamo hub: around $150-300. Battery charger: <$30. And you might want a battery charger even if you have a dynamo hub.

That is, maybe, people should see how well the battery charger works before jumping to a dynamo hub.
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