Re: leisure Battery

by meanchris Mon Nov 13, 2017 10:37 am

I presume that he means the total electrical work done to describe the chemical changes and thus charge imparted to the battery?

by Peter Brown Mon Nov 13, 2017 10:41 am

meanchris wrote:I presume that he means the total electrical work done to describe the chemical changes and thus charge imparted to the battery?

So do I but I've never seen the unit related to battery engineering.

by rgermain Mon Nov 13, 2017 11:22 am

meanchris wrote:
rgermain wrote:
meanchris wrote:
rgermain wrote:Maplin have one at £9.99! I wonder if it is any good at that price?
Oh dear I see why, only AC current!

Believe me, (look into the eyes, not around the eyes), the UNI-T UT210E is the only good Hall Effect contender at anywhere near that price.

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Yep, one is on it's way to me, UNI-UT210E that is, Thanks for the link.

Richard

A couple of tips:

1. Remember that it's very sensitive on the low DC current ranges, you MUST zero it and then keep it in the same orientation to avoid magnetic field errors.

2. DON'T use it to measure the van's engine start current, you'll magnetise the clamp ferrite and have to de-gauss it to make it work properly again, (not a permanent disaster though).

3. Use the NCV setting to check for live 230V AC, it actually works extremely well with a series of faster and faster beeps, the closer you get to a live conductor.
You can use it to check that there's a supply at a campsite EHU socket for example, it will even tell you which socket pin is the 'live'.
You don't have to clamp it around a cable for this, just point the bump on the tip of the clamp to where you want to check, it beeps when it's about 1cm from a live cable.

Thank you, I will bear your very useful comments in mind when my reader arrives.

by rgermain Mon Nov 13, 2017 11:27 am

TravelKat wrote:
rgermain wrote:
TravelKat wrote:
rgermain wrote:
Has anyone on here had any luck getting a leisure battery changed FOC under warranty? as I see A/S give it 3 mths!!!!!!!
We were in exactly the same boat about a month ago, vehicle about the same age, I posted on here about it. No luck with the dealer, and as for AS? Forget it, the reply was along the lines of: you can send the battery back to us, but experience has shown us that the fault usually lies with the user. AS also told us that they changed the terms of battery warranty in 2010, as they got a lot of claims until then, which were proven to be the fault of the user, that's why now it's only 90 days.

If you're interested, the link to that thread: [You must be registered and logged in to see this link.]

Thank you for your help. Yes thought that would be the case. 90 days! when it's been standing in their workshop/ forecourt! for ages discharged, utter disgrace to A/S again.
That is exactly how we felt/feel. My OH is extremely technically competent (he earned his living in electronics) and saw red when the reply stated that they were sure they would find the battery had not been charged correctly! AS manager even stated in his reply that the charge on the battery was measured in amps, again, red rag to my OH, who replied that the charge is measured in joules, ie watt/seconds. Needless to say we didn't get a reply back, nor a new battery!

Me also, I worked on Telephone Exchanges from the huge lead acid open cells to the sealed modern ones, never had a major problem.

As I said before, going to dealer on Thursday for FOC awning replacement, yes FOC content

so will mention the battery, watch this space as they say.

Richard

by AutoSleepy_Don Mon Nov 13, 2017 11:57 am

TravelKat wrote:charge is measured in joules, ie watt/seconds.

If I may correct your typo, "charge (rate of energy transfer) can be measured in joules/second i.e. watts."

by GP1069 Mon Nov 13, 2017 8:00 pm

Joules to watts calculation

The power P in watts (W) is equal to the energy E in joules (J), divided by the time period t in seconds (s):
P_(W) = E_(J) / t_(s)

For info and other calculators
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by greycaster Mon Nov 13, 2017 8:51 pm

Great bit of kit for checking what's draining your battery, from Maplins £9.99.
400mm Automotive Current Standard Blade Type Tester
Code: N48CY

by Peter Brown Mon Nov 13, 2017 10:24 pm

greycaster wrote:Great bit of kit for checking what's draining your battery, from Maplins £9.99.
400mm Automotive Current Standard Blade Type Tester
Code: N48CY

I have this and there is a problem with it. The blades are thicker than standard fuse blades so after you've inserted it in a fuse holder, the fuse holder contacts are stretched and the original fuse is loose and doesn't contact well.

by TravelKat Tue Nov 14, 2017 9:43 am

GP1069 wrote:
Joules to watts calculation

The power P in watts (W) is equal to the energy E in joules (J), divided by the time period t in seconds (s):
P_(W) = E_(J) / t_(s)

For info and other calculators
[You must be registered and logged in to see this link.]

This is TravelKat's OH: yes, that is correct, thanks.

by greycaster Tue Nov 14, 2017 10:15 am

Just checked my Maplins tester against a blade fuse and they are to the eye identical. I used to trace where my current drain was and had no difficulty inserting into the fuse holder. Old fuse put back in and felt secure. I have just purchased my tester, maybe they have updated to resolve the problem you had.

by Peter Brown Tue Nov 14, 2017 10:29 am

greycaster wrote:Just checked my Maplins tester against a blade fuse and they are to the eye identical. I used to trace where my current drain was and had no difficulty inserting into the fuse holder. Old fuse put back in and felt secure. I have just purchased my tester, maybe they have updated to resolve the problem you had.

That's possible, its also maybe because, in the two that gave me real problems, the fuse holder was actually made up of two female lucar connectors rather than a spring receptacle. It was embarrassing as one was in the EM40 of a friends brand new van!!

PS. No one has yet pointed me at any battery related literature that uses the joule to express battery charge or discharge performance?

by brodco Tue Nov 14, 2017 10:41 am

Hi

Peter Brown wrote:PS. No one has yet pointed me at any battery related literature that uses the joule to express battery charge or discharge performance?

I don’t think you’ll find any so this is probably it. hugegrins

Peter Brown wrote:A joule is electrical energy equal to the work done when a current of 1 ampere is passed through a resistance of 1 ohm for 1 second. I've never heard of a joule being used to record the rate of charge or discharge of a battery. I would be grateful if someone can point me at some relevant literature?

I haven’t either bit you but I suppose you “could” quote it in joules (unless you can find anything wrong with my reasoning).

As an example using a 12V 100 Ah battery and for argument s sake lets assume it’s an ideal (i.e. perfect) battery. Say it’s giving a current of 10 A = 120W i.e. it’s transferring energy at the rate of 120 Joules per second.

If it does this for 10 hours ( 10 A for 10 hours = 100 Ah) it has transferred 120 Joules per second for 10x60x60 = 36000 seconds.

Or 4.32 million Joules (4.32MJ). So you "could" say it's a 4.32 MJ battery.

That would be OK if every battery was capacity was quoted in the same way but they aren’t they are quoted in Amp hours (not Amps). Amp hours is (are?) a measure of charge not energy.

AutoSleepyDon wrote:
TravelKat wrote:charge is measured in joules, ie watt/seconds.
If I may correct your typo, "charge (rate of energy transfer) can be measured in joules/second i.e. watts."

To be pedantic (who me) I think you need to leave “charge” off of that statement since charge is not a measure of energy.

Just for completeness. Charge is a dimensionless quantity, just a multiple of the elementary charge (e) equal to the charge on the electron. You don’t get energy until you introduce a voltage (the electron volt as a basic unit).

Interesting to anyone interested in the physics of batteries but if you’re not don’t worry about it. But Peter (who I’m sure knows this already) did ask for it. Anybody dissagree hugegrins

Brod

by Peter Brown Tue Nov 14, 2017 11:14 am

by rgermain Tue Nov 14, 2017 11:44 am

PLOUGHLIN wrote:Tanya still have them [You must be registered and logged in to see this link.]

A recent thread on here said AS only guarantee for 90 days. Sounds like one of the cells has failed.

I am totally confused with these battery specifications. As it looks like I need a replacement what do all these types mean? IE Tayna recommend a EXV105 calcium whereas the existing is a XV27MF what ever those numbers mean, to me it is just a battery which stores charge and delivers when I need power.

Does it harm things if I go for a higher AH, I do understand that it has more capacity, will the charger etc cope?

Silly questions but like everything these days- just so much choice. Of course I could always just let the dealer fit one and leave it at that.

Hope all this makes sense, as I blowing my senior brain!

Richard

by Peter Brown Tue Nov 14, 2017 11:55 am

I suggest you go to Halfords and ask them to replace it with an equivalent size and capacity battery. They will do that at no extra charge and there are plenty of branches to go to if you have trouble whilst its in warranty.

by rgermain Tue Nov 14, 2017 11:59 am

Peter Brown wrote:I suggest you go to Halfords and ask them to replace it with an equivalent size and capacity battery. They will do that at no extra charge and there are plenty of branches to go to if you have trouble whilst its in warranty.

Thanks Peter, I had thought of Halfords, the local branch is only a mile from us. I will give them a try.

Richard

by meanchris Tue Nov 14, 2017 12:41 pm

brodco wrote:Anybody dissagree

Brod

No, except maybe to suggest that 'charge' is being used as a generic English term here to express potential energy.

It can be mechanical: The charge in an air rifle spring.
It can be electrical: The charge in a capacitor.
It can be chemical: The charge in a battery.

I find the truly astonishing and fascinating thing about them all, is that they're related at their roots to the fundamental relativistic structure of our universe by a very simple and elegant equation.

by AutoSleepy_Don Tue Nov 14, 2017 4:07 pm

brodco wrote:
Just for completeness. Charge is a dimensionless quantity, just a multiple of the elementary charge (e) equal to the charge on the electron. You don’t get energy until you introduce a voltage (the electron volt as a basic unit).

Anybody dissagree

I sense you are looking for someone to disagree with you :-)

You say charge is dimensionless but wikipedia says a common unit for electrical charge is Ah amp hours. see wikipedia [You must be registered and logged in to see this link.]
Surely that means you are wrong to say charge is dimensionless.

leisure Battery - Page 2 2017-110

by Peter Brown Tue Nov 14, 2017 4:18 pm

AutoSleepyDon wrote:
brodco wrote:
Just for completeness. Charge is a dimensionless quantity, just a multiple of the elementary charge (e) equal to the charge on the electron. You don’t get energy until you introduce a voltage (the electron volt as a basic unit).

Anybody dissagree
I sense you are looking for someone to disagree with you :-)

You say charge is dimensionless but wikipedia says a common unit for electrical charge is Ah amp hours. see wikipedia [You must be registered and logged in to see this link.]
Surely that means you are wrong to say charge is dimensionless.

Brodco is correct, there is no dimension to charge, it doesn't exist as an entity. Charge is just a description of a process of energy transfer.

by AutoSleepy_Don Tue Nov 14, 2017 4:22 pm

Peter Brown wrote:Brodco is correct, there is no dimension to charge, it doesn't exist as an entity. Charge is just a description of a process of energy transfer.

Do you offer any explanation for the fact that charge is quantified in units of amp hours? (supported by wikipedia)

If you can't disprove that then Brodco is wrong.
It is wrong to say electric charge is a dimensionless quantity.

by Peter Brown Tue Nov 14, 2017 4:58 pm

AutoSleepyDon wrote:
Peter Brown wrote:Brodco is correct, there is no dimension to charge, it doesn't exist as an entity. Charge is just a description of a process of energy transfer.
Do you offer any explanation for the fact that charge is quantified in units of amp hours? (supported by wikipedia)

If you can't disprove that then Brodco is wrong.
It is wrong to say electric charge is a dimensionless quantity.

Just a reminder as to why this debate started; a statement was made that it is incorrect to describe the process of charging a battery as current flow (amps) over a period of time (hours) and that it should be described as a quantity of joules.

The question was asked, is anyone aware of the unit of a joule being conventionally used in reference to the charging of a battery and the consensus of opinion of the members of this forum is no, the process of charging a battery is described in ampere hours.

Conventionally, a dimension is a unit that can be used to describe something that exists eg. a box, a tank of fuel or in this case, the amount of energy available to be taken from a battery and it in this context that Brodco describes the process of charging a battery as dimensionless because it doesn’t actually exist. An analogy would be walking down the street, the distance between the start and the end of the walk is a dimension, the actual process of walking is not.

There is a Spectral Dimension that describes how things spread through a medium over time but, in my view that doesn’t apply here as the current is being pushed through the circuit by an electromotive force.

by brodco Wed Nov 15, 2017 11:26 am

Hi

AutoSleepyDon wrote:I sense you are looking for someone to disagree with you :-)

You sense correctly. I like a good chin wag even if it is a virtual one. The more opposing views the better; it makes things more interesting.

AutoSleepyDon wrote:Do you offer any explanation for the fact that charge is quantified in units of amp hours? (supported by wikipedia)

Hopefully it said “Electric Charge” I think Peter was trying to explain the difference with is walking analogy.

Charge (the fundamental charge quantum) has a value of 1. It’s dimensionless and not derived from anything else.

The “Electric Charge” that we refer to in electrical work is a quantised version defined as a certain number of charges flowing in past a point in a given time. 1 Coulomb (a specific number of charges albeit a big one) flowing in one second is defined as 1 Amp. So “Electric Charge” has the dimension of current x time whereas charge itself doesn't.

If you look at this list of SI units you’ll find Charge and Electric Charge listed separately.

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That said I see I fell into the same trap myself in an earlier post: think_smiley_46

brodco wrote:That would be OK if every battery was capacity was quoted in the same way but they aren’t they are quoted in Amp hours (not Amps). Amp hours is (are?) a measure of charge not energy.

I should of course have specified “electric charge”.

It still holds that electric charge by itself is not a measure of energy transfer.

Brod

by rgermain Wed Nov 15, 2017 1:15 pm

I never thought my original topic would get so technical and become such a slanging match.

I only wanted simple advice about my leisure battery sitting at 11.2v

Still nice to know it got so many reply's

Richard

by meanchris Wed Nov 15, 2017 1:19 pm

It's not so much a "slanging match", more like a nerd fight. hugegrins

by Peter Brown Wed Nov 15, 2017 1:40 pm

Now that made me smile. You probably gathered I've been a bit bored for the last few days. We're off in the van tomorrow for 10 days so I wont be a nuisance for a bit.