Help! Testing Dynamo output

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HUX
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Help! Testing Dynamo output

Post by HUX » Sun Oct 21, 2018 4:17 pm

Guys how do I check my dynamo output. I have a new Love Mud Juice boost hub 6v 3W and whilst it does power my light it's not as bright as I expected and my phone won't charge off my sinewave revolution even though it says it's charging. They are switched so run independently. When I stick the volt meter on the cable from the hub and the hub itself it fluctuates between 0 and 0.8v. Any ideas? it doesn't seem right to me.
Checked the meter on a AA
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Heath Robinson testing contraption
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whitestone
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Re: Help! Testing Dynamo output

Post by whitestone » Sun Oct 21, 2018 4:29 pm

Dynamos/generators are AC not DC!

The useful output is the DC side of the converter and for that I use a Muker in-line USB meter https://www.amazon.co.uk/MUKER-V21-Mult ... 01BUQ5I3G/
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Dave Barter
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Re: Help! Testing Dynamo output

Post by Dave Barter » Sun Oct 21, 2018 5:04 pm

Massive round of applause for the test bicycle
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pistonbroke
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Re: Help! Testing Dynamo output

Post by pistonbroke » Sun Oct 21, 2018 5:22 pm

Be careful not to run the wheel backwards as this will cause an interruption in the space time continuum and a black hole to form. (Warning this may be bollocks) I'd probably have mounted the wheel against my bench grinder wheel to give a constant speed but this almost certainly wouldn't have ended well. Good job you're not a member of any of the emergency services which tend to frown on messing about with electricity :geek:

mat_swan
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Re: Help! Testing Dynamo output

Post by mat_swan » Sun Oct 21, 2018 7:19 pm

Be careful not to run the wheel backwards as this will...
...condense static electricity out of the air to cope with the dynamo contacts in negative polarity. Spin it backwards fast enough and you'd best watch out for lightning.

I would also like to applaud the test setup

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larsmars
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Re: Help! Testing Dynamo output

Post by larsmars » Sun Oct 21, 2018 8:32 pm

HUX wrote:Guys how do I check my dynamo output. I have a new Love Mud Juice boost hub 6v 3W and whilst it does power my light it's not as bright as I expected and my phone won't charge off my sinewave revolution even though it says it's charging. They are switched so run independently. When I stick the volt meter on the cable from the hub and the hub itself it fluctuates between 0 and 0.8v. Any ideas? it doesn't seem right to me.
Checked the meter on a AA
Image
Heath Robinson testing contraption
Image
I can’t quite see what you are doing there. You won’t be able to to get max power even with your Rube Goldberg machine. Try riding 25k/hr for a few minutes. You will be surprised how much speed is required to sustain a decent recharge with the Sinewave. Unless you are riding roads you will be on trickle charge and dims lights, especially if you are expecting to run lights and Sinewave concurrently.

slarge
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Re: Help! Testing Dynamo output

Post by slarge » Sun Oct 21, 2018 9:05 pm

Hux, as Bob says, set the voltmeter to AC. You should be getting 6v with a load across the output (have you got a Revo or similar) and without a load across the output you might get up to 30v .

And yes, top marks for the test bicycle!

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sean_iow
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Re: Help! Testing Dynamo output

Post by sean_iow » Sun Oct 21, 2018 9:17 pm

Have you used the light with another hub and thought that it was brighter before?

When I first got my Revo I didn't think it seemed bright enough. It's meant to be 800 lumens but it didn't seem as bright as my 400 lumen head light. But having looked into it the Revo beam is wider so the lumens are spread out over a bigger area so the centre is less spotty if that makes sense.

As for charging devices, I've no personal experience of it but when I was researching it that it seems you need to ride quite quickly for a long time to charge anything up. Better for road tours or charging devices with low power demands, so not modern smartphones :smile:
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lune ranger
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Re: Help! Testing Dynamo output

Post by lune ranger » Sun Oct 21, 2018 10:21 pm

My experience of the Juice Vs a SON is that it has poor output. As you experience I got poor lighting at night and next to no charging by day.
I had other problems with the Juice and eventually got a refund and moved over to a SON. On the recent BB200 in the 10hrs of daylight on Saturday I charged an iPhone 5. It only dropped from 100% to 40% with an average overall speed of around 8.5kmh. At night the Revo was ok but no where near bright enough when riding on slow off road climbs or on HaB.
On my road setup riding keeps my iPhone at 100% charge and lighting with an Edelux 2 is fine at all times.
I charge using an Igaro and have a switch to select either charging or lighting.

HUX
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Re: Help! Testing Dynamo output

Post by HUX » Sun Oct 21, 2018 10:35 pm

Thanks all. I've bought 1 of those gadgets for a fiver to check the output of the sinewave. It does look like you need a decent constant speed to get any charge so not ideal for off road. The light is adequate but is a very wide beam pattern with no real spot. I guess I'll just experiment and see what it's capable of. Maybe I was expecting too much from it as it's advertised as plug and play!

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sean_iow
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Re: Help! Testing Dynamo output

Post by sean_iow » Sun Oct 21, 2018 10:44 pm

I think we've been spoilt by high output battery lights that make riding at night as light as the day time. I'm used to the revo now but I also have a joystick on my helmet for technical bits but most of the time the revo is plenty enough to see where I'm going.
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Bearbonesnorm
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Re: Help! Testing Dynamo output

Post by Bearbonesnorm » Mon Oct 22, 2018 9:30 am

I'd also say that dynamo lights seem a little dim when coming from modern battery stuff and the problem is worse at low speeds. I've found the Revo to be poorer at low speed than the K-lites, I put this down to the Revo having a larger capacitor ... but I could be wrong.
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rufus748
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Re: Help! Testing Dynamo output

Post by rufus748 » Mon Oct 22, 2018 11:46 am

I spoke to Kerry before buying the klite when I was having problems with my revo (being too dim at low speeds)
I recall he designed both and only wanted 3 'bulbs' in the Revo, exposure insisted in 4 which it doesn't have the power to property supply at low speeds.
He described the Revo as a road light which is why he went on to build his own

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larsmars
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Re: Help! Testing Dynamo output

Post by larsmars » Mon Oct 22, 2018 12:38 pm

rufus748 wrote:I spoke to Kerry before buying the klite when I was having problems with my revo (being too dim at low speeds)
I recall he designed both and only wanted 3 'bulbs' in the Revo, exposure insisted in 4 which it doesn't have the power to property supply at low speeds.
He described the Revo as a road light which is why he went on to build his own
I don't think Kerry designed the Revo. My understanding is that was inspired by a design called the Deanamo by Rob Dean.

I've got both a updated kLite and the Revo. The kLite is brighter at lower speeds and is a damn good light, but the standlight on the Revo lasts much longer at low intensity. Unfortunately, I find the kLite is a bit more cumbersome with the external standlight pack and switches and wires. They are both great lights in my opinion.

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Bearbonesnorm
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Re: Help! Testing Dynamo output

Post by Bearbonesnorm » Mon Oct 22, 2018 1:17 pm

The kLite is brighter at lower speeds and is a damn good light, but the standlight on the Revo lasts much longer at low intensity.
Which are the reasons why I've always assumed the Revo has a larger capacitor.
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rufus748
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Re: Help! Testing Dynamo output

Post by rufus748 » Mon Oct 22, 2018 3:10 pm

larsmars wrote:I don't think Kerry designed the Revo. My understanding is that was inspired by a design called the Deanamo by Rob Dean
Ah, I don't know about that. Came from the horses mouth. Could have been an over enthusiastic sales pitch, but it worked.

HUX
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Re: Help! Testing Dynamo output

Post by HUX » Mon Oct 22, 2018 5:35 pm

I read something this morning written by Kerry saying that he spent ages developing the K Lite only for it to be copied by Exposure and when the Revo came out everyone wanted 1 because they'd never heard of k-lite despite it being better. The power of marketing was mentioned! Needless to say he was properly pissed off.
Back to my issues. Tested the sinewave and it is kicking out 5v but cannot get an amp reading. Connected it up to a 12v battery and tried to charge my old samsung.managed 7%in half an hour. Not great.Put it back on the bike and within half an hour of riding phone was up by 25%. Great. Plugged in new samsung for an hour and nothing 0%. Back to the old phone for half an hour of riding and nothing 0% improvement. 20 min back home and it was up by 20%. So it does work...when it feels like it. Doesn't like my new phone though ~X(
It might be the lead,will do dome more experimenting :???:

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larsmars
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Re: Help! Testing Dynamo output

Post by larsmars » Mon Oct 22, 2018 8:52 pm

HUX wrote:I read something this morning written by Kerry saying that he spent ages developing the K Lite only for it to be copied by Exposure and when the Revo came out everyone wanted 1 because they'd never heard of k-lite despite it being better. The power of marketing was mentioned! Needless to say he was properly pissed off
That’s pretty much how I remember hearing/reading it.

Sorry to hear of the issues with the Samsung phone. Have you tried charging a USB cache battery instead? I’ve resorted to that for my Sinewave because I found the constant speed changes resulted in unreliable charging of my garmin and phone.

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Mart
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Re: Help! Testing Dynamo output

Post by Mart » Tue Oct 23, 2018 2:43 pm

larsmars wrote:
rufus748 wrote:I spoke to Kerry before buying the klite when I was having problems with my revo (being too dim at low speeds)
I recall he designed both and only wanted 3 'bulbs' in the Revo, exposure insisted in 4 which it doesn't have the power to property supply at low speeds.
He described the Revo as a road light which is why he went on to build his own
I don't think Kerry designed the Revo. My understanding is that was inspired by a design called the Deanamo by Rob Dean.

I've got both a updated kLite and the Revo. The kLite is brighter at lower speeds and is a damn good light, but the standlight on the Revo lasts much longer at low intensity. Unfortunately, I find the kLite is a bit more cumbersome with the external standlight pack and switches and wires. They are both great lights in my opinion.

Some mention here http://robdeanhove.blogspot.com/2011/12 ... go-go.html
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