Yet Another Cycling Forum

General Category => The Knowledge => GPS => Topic started by: Oscar's dad on September 14, 2018, 03:43:18 pm

Title: Which battery pack?
Post by: Oscar's dad on September 14, 2018, 03:43:18 pm
I like running my Garmin Extrex E30 off an external battery pack via a USB lead.  I purchased a nice looking Zendure battery pack which allows through charging.  But, it powers the Garmin about 30 second then stops so the E30 bleeps asking if I want to switch off, if I click NO it swaps to its onboard AA cells.

None of my other battery packs behave lke this and they all claim to having an output of 2.4 amps just like the Zendure.  I don't think the Zendure is at fault as it will charge my iPhone perfectly.

Any ideas?  Does a Garmin need some sort of weird power input?

Thanks in advance.
Title: Re: Which battery pack?
Post by: Feanor on September 14, 2018, 06:07:50 pm
I expect the Garmin is drawing so low a current that the battery pack has decided its time to switch off.

Different battery packs will have different minimum thresholds and will behave differently.
Title: Re: Which battery pack?
Post by: andyoxon on September 14, 2018, 07:10:01 pm
You could try having the Etrex backlight on while charging, and then find the minimum necessary BL level required to keep power bank on.
Title: Re: Which battery pack?
Post by: JohnL on September 15, 2018, 06:29:55 pm
Out of curiosity, why?

My Etrex 30 lasts 24 hours on rechargeable batteries, with the backlight on, and it’s very simple to swap to a second pair of batteries. Why use the external battery with all the associated issues when using it in the rain?

Just curious.
Title: Re: Which battery pack?
Post by: Oscar's dad on September 17, 2018, 03:30:30 pm
You could try having the Etrex backlight on while charging, and then find the minimum necessary BL level required to keep power bank on.

I always have the BL on and it doesn't make any difference.

Out of curiosity, why?

My Etrex 30 lasts 24 hours on rechargeable batteries, with the backlight on, and it’s very simple to swap to a second pair of batteries. Why use the external battery with all the associated issues when using it in the rain?

Just curious.

OK, that's interesting.  I'm sure my E30 doesn't last that long but perhaps I will give it a try again.
Title: Re: Which battery pack?
Post by: simonp on September 17, 2018, 03:31:59 pm
I've done 24h - usually leave backlight on a timeout (15s) rather than on all the time.

If it's raining, opening the back of the garmin to change batteries is not ideal, though. I had issues one LEL doing this.
Title: Re: Which battery pack?
Post by: Oscar's dad on September 17, 2018, 03:35:02 pm
I like having the BL on all the time, particularly at night when following a track as it won't light up automatically at turns as it would when following a route.
Title: Re: Which battery pack?
Post by: zigzag on September 17, 2018, 03:47:03 pm
i wouldn't recommend using usb changing all the time as vibration will damage the contacts in the socket and the unit will become unusable. i've had this on my gps, and now only use the cable to charge on the go when really necessary.
Title: Re: Which battery pack?
Post by: Oscar's dad on September 17, 2018, 03:51:36 pm
i wouldn't recommend using usb changing all the time as vibration will damage the contacts in the socket and the unit will become unusable. i've had this on my gps, and now only use the cable to charge on the go when really necessary.

On the Etrex it doesn’t charge, just powers the unit via the USB.
Title: Re: Which battery pack?
Post by: simonp on September 17, 2018, 03:54:36 pm
i wouldn't recommend using usb changing all the time as vibration will damage the contacts in the socket and the unit will become unusable. i've had this on my gps, and now only use the cable to charge on the go when really necessary.

On the Etrex it doesn’t charge, just powers the unit via the USB.

It doesn't make any difference to ZigZag's point - the issue is the socket being in use during riding.

I've been using rechargeable batteries in Etrex GPS devices since about 2006. They're a good option despite my earlier caveat. Use good quality batteries and a good charger if going this way.
Title: Re: Which battery pack?
Post by: Oscar's dad on September 17, 2018, 04:02:44 pm
i wouldn't recommend using usb changing all the time as vibration will damage the contacts in the socket and the unit will become unusable. i've had this on my gps, and now only use the cable to charge on the go when really necessary.

On the Etrex it doesn’t charge, just powers the unit via the USB.

It doesn't make any difference to ZigZag's point - the issue is the socket being in use during riding.


Sure, to be honest I haven't had an issue [famous last words!  ;D  ]
Title: Re: Which battery pack?
Post by: Kim on September 17, 2018, 04:44:56 pm
I expect the Garmin is drawing so low a current that the battery pack has decided its time to switch off.

Different battery packs will have different minimum thresholds and will behave differently.

This.  An eTrex uses very little power, compared to the charging phone the battery packs are designed for.  I measure a draw of about 70mA from my eTrex 30 with the backlight off and 110mA with the backlight at full brightness.  (I did some proper measurements with a µCurrent and an oscilloscope a while ago, which I detailed in a post somewhere that I can't now find.)

Second the point that one of the main advantages of an eTrex is that you don't have to do this USB-power-on-the-move nonsense.  Mini-USB sockets are neither waterproof nor durable, and AA batteries are cheap, readily available, easy to swap and give somewhere over 20 hours runtime (decent NiMH recharagable or primary Lithium cells, alkalines are disappointing).

FWIW my Anker PowerCore Speed 20000 has been powering my eTrex 30 (sitting on the menu screen with with the backlight and GPS receiver switched off) since I started writing this post, and shows no signs of switching off.  It will also stay on and power my phone after it is fully charged (which I consider an advantage, YMMV) where my Aukey PB-T9 and EasyAcc PB12000A did not.  Might be a bit overkill for using on the bike, audaxer-who-bought-an-Edge-style, but on the other hand it's an excellent choice for touring, as it appears to do the Right Thing in response to fluctuating input (as from a dynamo charger or solar panel) and in combination with a QC3 compatible wall-wart, it can charge at 15W.


ETA: After >10 minutes, the Anker was still powering the eTrex.  I tried the Aukey and it switched off after about 30 seconds.  The EasyAcc switched itself off even more quickly.  That's all the power banks I have to hand.
Title: Re: Which battery pack?
Post by: frankly frankie on September 17, 2018, 06:39:36 pm
If it's raining, opening the back of the garmin to change batteries is not ideal, though. I had issues one LEL doing this.

Once you know what sort of runtime to expect, you can always do your battery change at a control, without wasting any time - never in the wet and dark by the roadside.
Title: Re: Which battery pack?
Post by: Kim on September 17, 2018, 07:34:39 pm
IME it's not so much the rain, as the risk of the MicroSD card falling out on account of the crappy holder.
Title: Re: Which battery pack?
Post by: simonp on September 17, 2018, 07:53:18 pm
If it's raining, opening the back of the garmin to change batteries is not ideal, though. I had issues one LEL doing this.

Once you know what sort of runtime to expect, you can always do your battery change at a control, without wasting any time - never in the wet and dark by the roadside.

Indeed. Though some batteries are now reporting 1300mAh having started at 2500 so this can make it harder to avoid unexpected flat battery.
Title: Re: Which battery pack?
Post by: Oscar's dad on September 18, 2018, 01:00:38 pm
...FWIW my Anker PowerCore Speed 20000 has been powering my eTrex 30 (sitting on the menu screen with with the backlight and GPS receiver switched off) since I started writing this post, and shows no signs of switching off...

Thanks for the info Kim.  Does your Anker allow pass through charging?

I take folk's points about an eTrex not actually needing powering off an external battery pack and AAs being easy to swap and readily available etc.  Audaxing isn't really my thing but touring is.  I like being able to charge a battery pack off my dynohub and then powering all my devices off said battery pack without having to reply on AA cells.
Title: Re: Which battery pack?
Post by: andyoxon on September 18, 2018, 01:54:19 pm
Quote
3. Can Anker PowerCore portable chargers recharge themselves and charge my devices at the same time?

No, our portable chargers do not support what’s known as “pass-through” charging. (PowerCore Fusion56 will charge your device first, and then begin recharging itself, when plugged into a wall outlet.)

This was an intentional decision. When pass-through charging, if there is a difference between the output of the wall charger and the input requirement of the device being recharged, it causes the portable charger to power on and off rapidly. This increases total charging times, and can damage battery cells, decreasing the lifespan of both your device and the portable charger.
  http://community.anker.com/t/anker-faq-10-things-you-need-to-know-about-anker/57477

I have three Ankers of varying sizes, but don't require p-t charging.
Title: Re: Which battery pack?
Post by: Kim on September 18, 2018, 02:05:16 pm
...FWIW my Anker PowerCore Speed 20000 has been powering my eTrex 30 (sitting on the menu screen with with the backlight and GPS receiver switched off) since I started writing this post, and shows no signs of switching off...

Thanks for the info Kim.  Does your Anker allow pass through charging?

Can confirm that it doesn't.


Quote
I take folk's points about an eTrex not actually needing powering off an external battery pack and AAs being easy to swap and readily available etc.  Audaxing isn't really my thing but touring is.  I like being able to charge a battery pack off my dynohub and then powering all my devices off said battery pack without having to reply on AA cells.

That sounds like what I do (my audax rides will comfortably fit in a single charge).  I find a set of batteries lasts 2-3 days of touring.  I carry a spare pair of high-capacity NiMHs, a pair of emergency backup primary lithiums, and a small USB-powered 2xAA/AAA charger.  I'll generally charge AAs (and if I've used them, the AAAs from my auxiliary rear light) when I have access to mains or an abundance of solar power, but I can charge them with power from the USB power bank if necessary.
Title: Re: Which battery pack?
Post by: JohnL on September 20, 2018, 07:00:39 am
You could try having the Etrex backlight on while charging, and then find the minimum necessary BL level required to keep power bank on.

I always have the BL on and it doesn't make any difference.

Out of curiosity, why?

My Etrex 30 lasts 24 hours on rechargeable batteries, with the backlight on, and it’s very simple to swap to a second pair of batteries. Why use the external battery with all the associated issues when using it in the rain?

Just curious.

OK, that's interesting.  I'm sure my E30 doesn't last that long but perhaps I will give it a try again.

I only have the backlight on a couple of notches from the bottom. Most people I’ve seen complaining about battery life have the backlight way to high (often on full) which I find dazzling at night and eats batteries.
Title: Re: Which battery pack?
Post by: Kim on September 20, 2018, 01:30:45 pm
I only have the backlight on a couple of notches from the bottom. Most people I’ve seen complaining about battery life have the backlight way to high (often on full) which I find dazzling at night and eats batteries.

Agreed.  Full backlight is occasionally necessary for readability in the wrong kind of daylight, but in darkness a lower setting is more eye-friendly.

Of course, if the backlight's only coming on for a minute or so at junctions, it's not using that much energy anyway.
Title: Re: Which battery pack?
Post by: Kim on September 20, 2018, 01:55:53 pm
A friend of mine has started doing reviews of power banks, USB cables and the like.  He's not Big Clive, but he's thorough and independent (and has the sense to make good old-fashioned web pages for those of us who don't want to sit through a 20 minute video to find out if a given product is any good):  https://powerben.ch/
Title: Re: Which battery pack?
Post by: Oxford_Guy on September 20, 2018, 05:06:49 pm
That sounds like what I do (my audax rides will comfortably fit in a single charge).  I find a set of batteries lasts 2-3 days of touring.  I carry a spare pair of high-capacity NiMHs, a pair of emergency backup primary lithiums, and a small USB-powered 2xAA/AAA charger.  I'll generally charge AAs (and if I've used them, the AAAs from my auxiliary rear light) when I have access to mains or an abundance of solar power, but I can charge them with power from the USB power bank if necessary.

Which "small USB-powered 2xAA/AAA charger" do you use? I do have one, though think the one I have only works with AAs and it's very slow at charging, so am looking for something better. Thanks!
Title: Re: Which battery pack?
Post by: Kim on September 20, 2018, 06:03:52 pm
That sounds like what I do (my audax rides will comfortably fit in a single charge).  I find a set of batteries lasts 2-3 days of touring.  I carry a spare pair of high-capacity NiMHs, a pair of emergency backup primary lithiums, and a small USB-powered 2xAA/AAA charger.  I'll generally charge AAs (and if I've used them, the AAAs from my auxiliary rear light) when I have access to mains or an abundance of solar power, but I can charge them with power from the USB power bank if necessary.

Which "small USB-powered 2xAA/AAA charger" do you use? I do have one, though think the one I have only works with AAs and it's very slow at charging, so am looking for something better. Thanks!

It's a no-name piece of shit that came with some batteries.  It's fairly light, extremely slow, not at all durable, and has worked for the half a dozen times I've needed to recharge GPS batteries on tour.

I hear that there's an Ikea one that has proper independent charging channels, which is certainly an improvement.  No idea how fast it is.
Title: Re: Which battery pack?
Post by: Oxford_Guy on September 20, 2018, 06:21:24 pm
That sounds like what I do (my audax rides will comfortably fit in a single charge).  I find a set of batteries lasts 2-3 days of touring.  I carry a spare pair of high-capacity NiMHs, a pair of emergency backup primary lithiums, and a small USB-powered 2xAA/AAA charger.  I'll generally charge AAs (and if I've used them, the AAAs from my auxiliary rear light) when I have access to mains or an abundance of solar power, but I can charge them with power from the USB power bank if necessary.

Which "small USB-powered 2xAA/AAA charger" do you use? I do have one, though think the one I have only works with AAs and it's very slow at charging, so am looking for something better. Thanks!

It's a no-name piece of shit that came with some batteries.  It's fairly light, extremely slow, not at all durable, and has worked for the half a dozen times I've needed to recharge GPS batteries on tour.

Sounds not dissimilar to mine, though I've not used it much - have mostly been using my Wahoo Elemnt Bolt, but can see how an Etrex would be handy be longer Audax rides.

Quote
I hear that there's an Ikea one that has proper independent charging channels, which is certainly an improvement.  No idea how fast it is.

This one? It's cheap as chips, so could be worth as punt:

https://www.ikea.com/gb/en/products/smart-home-appliances/cables-chargers/vinninge-battery-charger-art-40303632/

It looks larger and probably heavier than the device I have, though

There's a reasonably detailed technical review here: https://lygte-info.dk/review/Review%20Charger%20Ikea%20Vinninge%20403.036.32%20UK.html
Title: Re: Which battery pack?
Post by: Oscar's dad on September 20, 2018, 06:30:45 pm
I’ve had a Technoline BL700 for many years, does a great job, not sure if they are still available.
Title: Re: Which battery pack?
Post by: Kim on September 20, 2018, 06:42:01 pm
I’ve had a Technoline BL700 for many years, does a great job, not sure if they are still available.

Yeahbut they're huge and run on a high-current 3V power supply.  Not something you're going to carry on a tour.

(BL700 is an excellent charger for home use.)


An often overlooked option for touring is that with the right settings the B&M e-Werk can be used to charge some combinations of cells directly, so you could use this to charge a pair of NiMH cells with a simple battery holder.  Pretty lightweight!
Title: Re: Which battery pack?
Post by: Oxford_Guy on September 21, 2018, 12:21:55 am
I’ve had a Technoline BL700 for many years, does a great job, not sure if they are still available.

There's the improved BL700N model, which looks great for home use, but doesn't look like it can be USB-powered and looks relatively large and heavy to carry on the bike.

http://www.batterylogic.co.uk/technoline/technoline-BL700.asp
Title: Re: Which battery pack?
Post by: Ham on September 21, 2018, 07:56:10 am
The lightest AA charger I have which travels with me when I need one is the 7DayShop one. Current version (https://www.7dayshop.com/products/7dayshop-fast-intelligent-lcd-display-mains-battery-charger-for-aa-aaa-nimh-rechargeable-batteries-wh2-ds-145) appears to be a revamp of the one I have in cream plastic with a flap. crucially it is fed electrons by an IEC C7 (figure of 8 ) lead straight from the mains, and has separate charging circuits for each cell and it weighs 104g.

(Model number of mine is 808LCD as https://www.amazon.co.uk/7dayshop-Intelligent-Battery-Charger-Display/dp/B002IW5LX4)

ETA one on the bay of thieves (https://www.ebay.co.uk/itm/Battery-Charger-7Dayshop-808LCD-for-AA-AAA-With-3-Power-Options-New/362439987399?epid=4022903741&hash=item54631b50c7:g:TlAAAOSwwNtbfDzd)
Title: Re: Which battery pack?
Post by: Kim on January 13, 2019, 09:49:31 pm
Follow-up on the subject of portable charging...

On the logic that the lightest charger is the one you're carrying already, I molished this adaptor for my e-Werk:

(http://www.ductilebiscuit.net/gallery_albums/kitchen_pr0n/2019_01_13_21_42_27.sized.jpg)

The idea being that if you set the output to 2.8V with an appropriate current limit[1], it can safely be used to charge a pair of NiMH cells in series.  Positive to positive (red wire on the battery clip to white wire on the e-Werk output cable), for those playing along at home.

Plus points:  It works, is compact and weighs very little, and potentially doubles as a convenient way to carry spare batteries.  Relatively unlikely to break from rattling around in your bag, unlike anything with a solidly-attached USB A plug on the end, and the batteries don't fall out.

Gotchas:  By stopping at 1.4V (which is necessary to avoid damaging the cells, this isn't measuring delta-V or temperature), the battery only gets to about 80% charged.  It's also fairly slow - I measured a little over 300mA into a pair of cells depleted to the point where the eTrex moans about low battery.  The current tails off as the voltage rises.

And obviously you need to power your e-Werk.  Riding your dynamo-equipped bike is traditional[2], but it's actually specified for both AC and DC input across a wide range of input voltages.  You could, for example, connect it to a 12V solar panel.  Or an e-bike battery.  And, interestingly, USB's 5VDC is just barely sufficient for this 2.8V charging, although the peak current is limited if there's any drop-out at all.

(This direct-connection-to-a-battery approach will work for other combinations of cells and chemistries, check the manual (http://en.bumm.de/fileadmin/user_upload/361/361_E-WERK_neu.pdf) for what's safe.)

Is it worth it?  Possibly.  I reckon you'd get better results with 18650 Lithium-ion cells.


[1] Keep it below 1C, which in practice means you can turn it all the way up for high-capacity AAs, but you might want to limit to 0.5A or so for AAAs.
[2] One advantage of directly charging batteries is they don't give a stuff about stop-start charging.
Title: Re: Which battery pack?
Post by: fhills on January 27, 2019, 09:16:00 pm
IME it's not so much the rain, as the risk of the MicroSD card falling out on account of the crappy holder.

Yes I lost one once. But that's what that old cyclist standby Duct tape is for. My Etrex 20 has a small bit in there permanently.
Title: Re: Which battery pack?
Post by: fhills on January 27, 2019, 09:18:41 pm
i wouldn't recommend using usb changing all the time as vibration will damage the contacts in the socket and the unit will become unusable. i've had this on my gps, and now only use the cable to charge on the go when really necessary.

On the Etrex it doesn’t charge, just powers the unit via the USB.

It doesn't make any difference to ZigZag's point - the issue is the socket being in use during riding.

I've been using rechargeable batteries in Etrex GPS devices since about 2006. They're a good option despite my earlier caveat. Use good quality batteries and a good charger if going this way.

Yes - I don't think usb sockets are up to this sort of thing. Pretty damn sure they weren't designed with this sort of use in mind.

I use rechargeables in my Etrex20 - works fine - feel no need to carry, let alone plug in, a power bank - bigger and heavier than a set or two of spare AAs