Does anyone know if these things just run at 12V? The reason I ask is
that to turn an engine over for 10 seconds would require 256 Farads of
capacitance, whereas if they pumped the voltage up to 120V they would
only require 6.4F.

AJH

In article ,
wrote:
Does anyone know if these things just run at 12V? The reason I ask is
that to turn an engine over for 10 seconds would require 256 Farads of
capacitance, whereas if they pumped the voltage up to 120V they would
only require 6.4F.

but they might burn out the windings of the starter motor - the insulation
might not like 120v.

--
from KT24 in Surrey, England

On 1/3/2017 4:08 PM, charles wrote:
In article ,
wrote:
Does anyone know if these things just run at 12V? The reason I ask is
that to turn an engine over for 10 seconds would require 256 Farads of
capacitance, whereas if they pumped the voltage up to 120V they would
only require 6.4F.

but they might burn out the windings of the starter motor - the insulation
might not like 120v.

Not to mention anything electronic. It would be nice to think that
everything would have effective protection these days, but do you think
it does?

Mind you, I think this is a troll.

On Tue, 03 Jan 2017 15:41:30 +0000, wrote:

Does anyone know if these things just run at 12V? The reason I ask is
that to turn an engine over for 10 seconds would require 256 Farads of
capacitance, whereas if they pumped the voltage up to 120V they would
only require 6.4F.

AJH

Supercapacitors are very low voltage, generally around 2 or 3 volts.
So you need a few in series just to get 12V.

Caecilius wrote:

Supercapacitors are very low voltage, generally around 2 or 3 volts.
So you need a few in series just to get 12V.

And then the capacitance goes down.

On Tue, 03 Jan 2017 17:07:30 +0000, Andy Burns wrote:

Caecilius wrote:

Supercapacitors are very low voltage, generally around 2 or 3 volts.
So you need a few in series just to get 12V.

And then the capacitance goes down.

If the OP is talking about what I think they are they (not the OP) are
LiPo batteries and SMPS to get 12V

Nomad

--
All Hell hadn't been let loose. It was merely Detritus. But from a few
feet away you couldn't tell the difference.
(The Fifth Elephant)
17:05:01 up 5 days, 5:32, 5 users, load average: 0.72, 0.49, 0.42

On 03/01/17 17:07, Andy Burns wrote:
Caecilius wrote:

Supercapacitors are very low voltage, generally around 2 or 3 volts.
So you need a few in series just to get 12V.

And then the capacitance goes down.



Well, the energy stored goes down for a given capacitance. The
capacitance itself is not related to voltage.

Seems like a bad idea anyway - the voltage on a capacitor drops quickly
as energy is removed. It's only going to work with a booster circuit -
and that's a chunky booster that can supply several hundred amps.

On Tuesday, 3 January 2017 16:28:54 UTC, Caecilius wrote:
On Tue, 03 Jan 2017 15:41:30 +0000, wrote:

Does anyone know if these things just run at 12V? The reason I ask is
that to turn an engine over for 10 seconds would require 256 Farads of
capacitance, whereas if they pumped the voltage up to 120V they would
only require 6.4F.

AJH

Supercapacitors are very low voltage, generally around 2 or 3 volts.
So you need a few in series just to get 12V.

They're also high resistance.

On Tue, 3 Jan 2017 17:09:13 -0000 (UTC), The Nomad
wrote:


If the OP is talking about what I think they are they (not the OP) are
LiPo batteries and SMPS to get 12V

No, I have seen those but this is what I was referring to:

http://www.koldban.com/KBi_KrankingKARTS_s/5.htm


So I had thought they might store charge at a higher voltage and then
control the current in some way.

Perhaps they just have much more capacitance than I thought was
possible.

AJH

On 1/3/2017 5:25 PM, Tim Watts wrote:
On 03/01/17 17:07, Andy Burns wrote:
Caecilius wrote:

Supercapacitors are very low voltage, generally around 2 or 3 volts.
So you need a few in series just to get 12V.

And then the capacitance goes down.



Well, the energy stored goes down for a given capacitance. The
capacitance itself is not related to voltage.

Seems like a bad idea anyway - the voltage on a capacitor drops quickly
as energy is removed. It's only going to work with a booster circuit -
and that's a chunky booster that can supply several hundred amps.

Yup. They don't hold charge long, though, you normally charge them
before use. They *claim* they can steal enough energy from a depleted
battery to work, not sure I would want to rely on that. I have a couple
of LiPo ones which are great (and hold their charge for several months).
Also conveniently have USB sockets for charging phones, and a torch and
sometimes flashing red lights.

On Tuesday, 3 January 2017 17:37:03 UTC, wrote:
On Tuesday, 3 January 2017 16:28:54 UTC, Caecilius wrote:
On Tue, 03 Jan 2017 15:41:30 +0000, wrote:

Does anyone know if these things just run at 12V? The reason I ask is
that to turn an engine over for 10 seconds would require 256 Farads of
capacitance, whereas if they pumped the voltage up to 120V they would
only require 6.4F.

AJH

Supercapacitors are very low voltage, generally around 2 or 3 volts.
So you need a few in series just to get 12V.

They're also high resistance.

Capacitors have virtually zero resistance,

On Tue, 03 Jan 2017 17:48:34 +0000, news wrote:

On Tue, 3 Jan 2017 17:09:13 -0000 (UTC), The Nomad
wrote:


If the OP is talking about what I think they are they (not the OP) are
LiPo batteries and SMPS to get 12V

No, I have seen those but this is what I was referring to:

http://www.koldban.com/KBi_KrankingKARTS_s/5.htm


So I had thought they might store charge at a higher voltage and then
control the current in some way.

Perhaps they just have much more capacitance than I thought was
possible.

AJH

Ah, OK, as you were then ...

How much $ ! (& how much - mass)

!!

Nomad



--
"Idiot I may be, but tied up I ain't."
-Gaspode the wonder dog
(Terry Pratchett, Moving Pictures)
18:50:01 up 5 days, 7:17, 5 users, load average: 0.64, 0.46, 0.36

On 03/01/2017 18:30, harry wrote:
On Tuesday, 3 January 2017 17:37:03 UTC, wrote:
On Tuesday, 3 January 2017 16:28:54 UTC, Caecilius wrote:
On Tue, 03 Jan 2017 15:41:30 +0000, wrote:

Does anyone know if these things just run at 12V? The reason I ask is
that to turn an engine over for 10 seconds would require 256 Farads of
capacitance, whereas if they pumped the voltage up to 120V they would
only require 6.4F.

AJH

Supercapacitors are very low voltage, generally around 2 or 3 volts.
So you need a few in series just to get 12V.

They're also high resistance.

Capacitors have virtually zero resistance,


Except when its infinite.

On Tue, 3 Jan 2017 17:57:55 +0000, newshound
wrote:

snip

Yup. They don't hold charge long, though, you normally charge them
before use. They *claim* they can steal enough energy from a depleted
battery to work, not sure I would want to rely on that.

Down to about 5V I think as they can also charge from a USB socket.

A mate has two (different 'powers') and says they do exactly what they
say on the tin. ;-)

Cheers, T i m

On Tuesday, 3 January 2017 18:30:14 UTC, harry wrote:
On Tuesday, 3 January 2017 17:37:03 UTC, tabby wrote:
On Tuesday, 3 January 2017 16:28:54 UTC, Caecilius wrote:
On Tue, 03 Jan 2017 15:41:30 +0000, wrote:

Does anyone know if these things just run at 12V? The reason I ask is
that to turn an engine over for 10 seconds would require 256 Farads of
capacitance, whereas if they pumped the voltage up to 120V they would
only require 6.4F.

AJH

Supercapacitors are very low voltage, generally around 2 or 3 volts.
So you need a few in series just to get 12V.

They're also high resistance.

Capacitors have virtually zero resistance,

heh


NT

On 03/01/17 17:57, newshound wrote:
On 1/3/2017 5:25 PM, Tim Watts wrote:
On 03/01/17 17:07, Andy Burns wrote:
Caecilius wrote:

Supercapacitors are very low voltage, generally around 2 or 3 volts.
So you need a few in series just to get 12V.

And then the capacitance goes down.



Well, the energy stored goes down for a given capacitance. The
capacitance itself is not related to voltage.

Seems like a bad idea anyway - the voltage on a capacitor drops quickly
as energy is removed. It's only going to work with a booster circuit -
and that's a chunky booster that can supply several hundred amps.

Yup. They don't hold charge long, though, you normally charge them
before use. They *claim* they can steal enough energy from a depleted
battery to work, not sure I would want to rely on that. I have a couple
of LiPo ones which are great (and hold their charge for several months).
Also conveniently have USB sockets for charging phones, and a torch and
sometimes flashing red lights.

I have a Li(Po?) one too and that is good. Started a VW 2l diesel with a
battery so dead it would not crank once.

But of course, Li batteries tend to hold their voltage over a range of
charge, whereas a capacitor loses voltage in proportion to charge (in
coulombs) so starts to fall off immediately upon discharge.

In article ,
writes:
On Tuesday, 3 January 2017 16:28:54 UTC, Caecilius wrote:
On Tue, 03 Jan 2017 15:41:30 +0000, wrote:

Does anyone know if these things just run at 12V? The reason I ask is
that to turn an engine over for 10 seconds would require 256 Farads of
capacitance, whereas if they pumped the voltage up to 120V they would
only require 6.4F.

AJH

Supercapacitors are very low voltage, generally around 2 or 3 volts.
So you need a few in series just to get 12V.

They're also high resistance.

Some older ones have a moderate internal resistance (often used
for things like memory backup in computers), but the ones used
for this are in the few milliohms range, lower than a typical
car battery.

--
Andrew Gabriel
[email address is not usable -- followup in the newsgroup]

On Tuesday, 3 January 2017 22:25:51 UTC, Andrew Gabriel wrote:
In article ,
tabbypurr@ writes:
On Tuesday, 3 January 2017 16:28:54 UTC, Caecilius wrote:
On Tue, 03 Jan 2017 15:41:30 +0000, wrote:

Does anyone know if these things just run at 12V? The reason I ask is
that to turn an engine over for 10 seconds would require 256 Farads of
capacitance, whereas if they pumped the voltage up to 120V they would
only require 6.4F.

AJH

Supercapacitors are very low voltage, generally around 2 or 3 volts.
So you need a few in series just to get 12V.

They're also high resistance.

Some older ones have a moderate internal resistance (often used
for things like memory backup in computers), but the ones used
for this are in the few milliohms range, lower than a typical
car battery.

yes, obviously.

On 04/01/17 00:24, Andrew Gabriel wrote:
In article ,
writes:
On Tuesday, 3 January 2017 16:28:54 UTC, Caecilius wrote:
On Tue, 03 Jan 2017 15:41:30 +0000, wrote:

Does anyone know if these things just run at 12V? The reason I ask is
that to turn an engine over for 10 seconds would require 256 Farads of
capacitance, whereas if they pumped the voltage up to 120V they would
only require 6.4F.

AJH

Supercapacitors are very low voltage, generally around 2 or 3 volts.
So you need a few in series just to get 12V.

They're also high resistance.

Some older ones have a moderate internal resistance (often used
for things like memory backup in computers), but the ones used
for this are in the few milliohms range, lower than a typical
car battery.

whoosh!

On 03/01/2017 17:48, wrote:
On Tue, 3 Jan 2017 17:09:13 -0000 (UTC), The Nomad
wrote:


If the OP is talking about what I think they are they (not the OP) are
LiPo batteries and SMPS to get 12V

No, I have seen those but this is what I was referring to:

http://www.koldban.com/KBi_KrankingKARTS_s/5.htm

So I had thought they might store charge at a higher voltage and then
control the current in some way.

Perhaps they just have much more capacitance than I thought was
possible.

In excess of 320F internal resistance 0.006R and with a voltage rating
of at least 15v. I looked for their Kold Ban patents:

http://www.google.co.uk/patents/US6988475

They claim it will survive 1000000 charge discharge cycles. I suspect
there is a limit to haw frequently you can use it sequentially.

It might just do what you want if you have money to burn but I find a
pair of jump leads and a cheap battery charger entirely adequate.

--
Regards,
Martin Brown

On 03/01/2017 17:37, wrote:
On Tuesday, 3 January 2017 16:28:54 UTC, Caecilius wrote:
On Tue, 03 Jan 2017 15:41:30 +0000, wrote:

Does anyone know if these things just run at 12V? The reason I ask is
that to turn an engine over for 10 seconds would require 256 Farads of
capacitance, whereas if they pumped the voltage up to 120V they would
only require 6.4F.

AJH

Supercapacitors are very low voltage, generally around 2 or 3 volts.
So you need a few in series just to get 12V.

Indeed (although that may help for charging them in parallel).

They're also high resistance.

Only if you consider 0.0005R a high resistance. The latest generation of
super and ultra capacitor have some impressive specs. Looks like the
device must be a stack of 1500F 2.7v ultracapacitors rated at 1kA. eg

http://www.maxwell.com/images/docume..._3000489_2.pdf

They are a far cry from memory preservation "super" capacitors of old.

--
Regards,
Martin Brown

On Tuesday, 3 January 2017 15:41:34 UTC, wrote:
Does anyone know if these things just run at 12V? The reason I ask is
that to turn an engine over for 10 seconds would require 256 Farads of
capacitance, whereas if they pumped the voltage up to 120V they would
only require 6.4F.

AJH

Here you go!

http://bit.ly/2iH7o4N

wrote:
On Tue, 3 Jan 2017 17:09:13 -0000 (UTC), The Nomad
wrote:

If the OP is talking about what I think they are they (not the OP) are
LiPo batteries and SMPS to get 12V

No, I have seen those but this is what I was referring to:

http://www.koldban.com/KBi_KrankingKARTS_s/5.htm


So I had thought they might store charge at a higher voltage and then
control the current in some way.

It's possible, but they're promising 3kA at 12V, which means needing a 36kW
(peak) inverter. That's not small - into serious EV territory here - and
needs careful cooling.

It seems they have a supercap with enough series/parallel cells to get the
voltage tolerance up (to 16V) so they don't need to power convert:
http://www.koldban.com/Kapower_Specifications_s/29.htm

Theo

On Wed, 4 Jan 2017 08:12:37 +0000, Martin Brown
wrote:

It might just do what you want if you have money to burn but I find a
pair of jump leads and a cheap battery charger entirely adequate.

Me too, I was just wondering how they worked as the biggest capacitor
I had ever seen was 1F which we used to store the charge for an
amplification system which was pumped up by a 24V bicycle generator (
sound system for an off grid concert).

AJH

On Wed, 04 Jan 2017 11:35:07 +0000, news wrote:


had ever seen was 1F which we used to store the charge for an
amplification system which was pumped up by a 24V bicycle generator (
sound system for an off grid concert).

Sounds like you used to run Raves! Was it you in Newcastle t'other day??
Police had to break into one of the bridges' towers to shut it down.

On Wed, 04 Jan 2017 10:51:46 -0600, Mark Allread
wrote:

On Wed, 04 Jan 2017 11:35:07 +0000, news wrote:


had ever seen was 1F which we used to store the charge for an
amplification system which was pumped up by a 24V bicycle generator (
sound system for an off grid concert).

Sounds like you used to run Raves! Was it you in Newcastle t'other day??
Police had to break into one of the bridges' towers to shut it down.

Some rave, it was an arts project at the gunpowder park in Waltham
Abbey, it needed two people cycling quite hard to maintain power
output sufficient to run the sound system.

AJH

On Wed, 04 Jan 2017 22:45:23 +0000, news wrote:

On Wed, 04 Jan 2017 10:51:46 -0600, Mark Allread wrote:

On Wed, 04 Jan 2017 11:35:07 +0000, news wrote:


had ever seen was 1F which we used to store the charge for an
amplification system which was pumped up by a 24V bicycle generator (
sound system for an off grid concert).

Sounds like you used to run Raves! Was it you in Newcastle t'other
day??
Police had to break into one of the bridges' towers to shut it down.

Some rave, it was an arts project at the gunpowder park in Waltham
Abbey,

Well it should have gone with a bang. I do hope the ordnance was
properly cleared beforehand - once had a similar 'cleared' site near us.
Until the builders found some bits of metal and ran like hell. A number
of controlled explosions followed.

it needed two people cycling quite hard to maintain power output
sufficient to run the sound system.


I'll bet.

On Thu, 05 Jan 2017 04:46:59 -0600, Mark Allread
wrote:

Well it should have gone with a bang. I do hope the ordnance was
properly cleared beforehand - once had a similar 'cleared' site near us.
Until the builders found some bits of metal and ran like hell. A number
of controlled explosions followed.

Our firm did some of the initial vegetation clearance but there were
some wooden huts we were not allowed to touch, they torched them as
the safest way of demolition but I didn't witness any of that.

I later mulched up a field on an old mortar range where a girl had
been killed in an explosion during the war, near Colchester, it had
been swept for bombs at the time and abandoned to secondary woodland,
a terrible waste of timber but the range was only closed for a week to
do the work. I was a little worried. After that job I was low loaded
to Hemel Hempstead where the exhaust broke, so a denizen of this group
helped me re weld it. Whilst I was away my "workmates" deposited a
mills bomb in the running gear for me to find. Whilst the pin and
handle were intact I could see the primer was missing from the bottom,
so I pointed it out to them, told them to move back and raised my
'phone to my ear to call the police :-)

AJH