shimano dynamo AXA Luxx 70 Biologic recharge issue

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DarkNewt
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shimano dynamo AXA Luxx 70 Biologic recharge issue

Post by DarkNewt »

Hi All,

I have a biologic reecharge wired into the converter and then into the same wiring as an axa luxx 70. All is working well, however i cannot find if I need to put an overvoltage protector between the lux 70 and the dynamo, anyone know?

many thanks.
Currently planning my next adventure and trying to get over two operations in 6 months but still going strong!
email: newt@systems-engineer.info web: thedarknewt.blogspot.co.uk
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[XAP]Bob
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Re: shimano dynamo AXA Luxx 70 Biologic recharge issue

Post by [XAP]Bob »

Axa should have one built in. That will also help protect the reecharge rectifier, which is apparently vulnerable. I wired my rear light in parallel with the reecharge to ensure it never took the full load from the dynamo (potentially without a battery to charge).
A shortcut has to be a challenge, otherwise it would just be the way. No situation is so dire that panic cannot make it worse.
There are two kinds of people in this world: those can extrapolate from incomplete data.
Brucey
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Re: shimano dynamo AXA Luxx 70 Biologic recharge issue

Post by Brucey »

if this is the standard Luxx 70 model (rather than the 'plus') and an alternate recharger is fitted in parallel, it isn't clear to me that the overvoltage protection built into the headlight will be active when the light is switched off. I guess it all depends if the switch in the lamp housing cuts everything or not.

Anyone got a circuit diagram or a photo of the main circuit board?

cheers
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~~~~~~~~~~~~~~~~~~~~~~Brucey~~~~~~~~~~~~~~~~~~~~~~~~
fatboy
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Re: shimano dynamo AXA Luxx 70 Biologic recharge issue

Post by fatboy »

I don't think you can rely on anything about the lamp to protect the Biologic charger which I've read need protecting. The input capacitor seems not to be rated high enough for the unloaded hub dynamo output. So I'd say yes you need over voltage protection of some sort.
"Marriage is a wonderful invention; but then again so is the bicycle puncture repair kit." - Billy Connolly
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[XAP]Bob
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Joined: 26 Sep 2008, 4:12pm

Re: shimano dynamo AXA Luxx 70 Biologic recharge issue

Post by [XAP]Bob »

I've had mine "protected" by having a rear light in parallel - the light is always on.

Even at speeds in excess of 50mph the reecharge has been fine...
A shortcut has to be a challenge, otherwise it would just be the way. No situation is so dire that panic cannot make it worse.
There are two kinds of people in this world: those can extrapolate from incomplete data.
edocaster
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Joined: 10 Apr 2013, 10:43pm

Re: shimano dynamo AXA Luxx 70 Biologic recharge issue

Post by edocaster »

If you just want to protect your Biologic Reecharge when your light is off, then you'll need to find something that can keep the voltage down. If you Google 'Shimano SM-DH10', then you can find a fairly basic overvoltage protector, which is generally fitted to rear lights in case the front blows.

Note there are at least two designs of the Biologic Reecharge regulator: The original 'shorter' unit with battery pack which you can see a picture of (a broken one) in one of the YACF threads (Google 'Dahon Ecologic REEcharge' (sic)), and then there's a longer unit, which doesn't come with the battery pack, which seems to be the current model (https://www.flickr.com/photos/14degrees/14475007124/). The longer Reecharge *might* have some form of protection, but as no-one has opened it up to look, we won't know...
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[XAP]Bob
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Re: shimano dynamo AXA Luxx 70 Biologic recharge issue

Post by [XAP]Bob »

Mine is the shorter one.

A rear light in parallel has given it sufficient protection to over 50mph, even when it has has a zero load output.
A shortcut has to be a challenge, otherwise it would just be the way. No situation is so dire that panic cannot make it worse.
There are two kinds of people in this world: those can extrapolate from incomplete data.
pete75
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Joined: 24 Jul 2007, 2:37pm

Re: shimano dynamo AXA Luxx 70 Biologic recharge issue

Post by pete75 »

If the voltage protection circuit in the light is anything more sophisticated than a zener diode it's likely it only protects where current is being drawn from it ie the light itself and the feed to to the rear light. If it is just a zener diode that may well be wired to work only when the light is switched on.
If you decide to use the Shimano SM-DH10 over voltage protector mentioned above PM me as I've bought several Shimano dynamos in the past couple of years and each came with an SM-DH10 which I've no use for.
'Give me my bike, a bit of sunshine - and a stop-off for a lunchtime pint - and I'm a happy man.' - Reg Baker
DarkNewt
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Joined: 12 Aug 2014, 9:55pm
Location: West Midlands

Re: shimano dynamo AXA Luxx 70 Biologic recharge issue

Post by DarkNewt »

Hi All,

apologies I went silent on this, I haven't been getting any prompts. I am going to add some recharge protection just to be on the safe side!

Many thanks for all your helpful replies as usual!

Newt
Currently planning my next adventure and trying to get over two operations in 6 months but still going strong!
email: newt@systems-engineer.info web: thedarknewt.blogspot.co.uk
edocaster
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Re: shimano dynamo AXA Luxx 70 Biologic recharge issue

Post by edocaster »

Note, if you put something like the SM-DH10 parallel to the Reecharge, it will almost always be in action (i.e. clamping the voltage) when you have the light off and nothing charging on the Reecharge. I.e. it will drag like, or worse than, having the lights on all the time (and probably start to heat up). To avoid this, you will have to put a switch in-line to break the circuit to the overvoltage protector and the Reecharge. In other words, you'll manually switch the circuit off, and the SM-DH10 will only be in action as a last resort if you forget to switch the circuit off.

This problem doesn't normally happen for the SM-DH10's intended usage (protecting rear lights) as both the rear lights and the protector are normally connected to the front light's special rear light output 'pigtails' - which are controlled by the front light's switch. So the protector is only in the circuit when the front light is switched on (and won't activate unless the front light fails to clamp the voltage itself). Hope that didn't end up sounding too confusing :wink:
DarkNewt
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Joined: 12 Aug 2014, 9:55pm
Location: West Midlands

Re: shimano dynamo AXA Luxx 70 Biologic recharge issue

Post by DarkNewt »

Hiya,

got that! I have decided to change my wiring so that I can include the over voltage protection and have a convenient waterproof switch for when neither lights are in use. The reecharge is good especially the pricepoint, however it's indicator lights are poorly placed so I may end up changing haven't decided yet - see if it's one of those things I get used too!

If it is of use to anyone I could do an easy to follow wiring diagram for my setup.
Currently planning my next adventure and trying to get over two operations in 6 months but still going strong!
email: newt@systems-engineer.info web: thedarknewt.blogspot.co.uk
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[XAP]Bob
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Re: shimano dynamo AXA Luxx 70 Biologic recharge issue

Post by [XAP]Bob »

I also have an inline switch feeding the rectifier - rarely use it, since I run enough USB powered electronics to require the battery is occasionally topped off at the mains.
A shortcut has to be a challenge, otherwise it would just be the way. No situation is so dire that panic cannot make it worse.
There are two kinds of people in this world: those can extrapolate from incomplete data.
DarkNewt
Posts: 388
Joined: 12 Aug 2014, 9:55pm
Location: West Midlands

Re: shimano dynamo AXA Luxx 70 Biologic recharge issue

Post by DarkNewt »

I use the recharge to keep a Garmin Touring Plus and a Garmin Virb topped up, and only activate the lights at night. Would be very rare for the recharge not to be powering something but safer than sorry.
Currently planning my next adventure and trying to get over two operations in 6 months but still going strong!
email: newt@systems-engineer.info web: thedarknewt.blogspot.co.uk
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