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UK diy (uk.d-i-y) For the discussion of all topics related to diy (do-it-yourself) in the UK. All levels of experience and proficency are welcome to join in to ask questions or offer solutions. |
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#1
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12V battery charger from Screwfix - specifications?
https://www.screwfix.com/p/streetwiz...matic-battery-
charger-12v/7752r#product_additional_details_container "12V automatic heavy duty plastic-cased battery charger for car, motorcycle and lawn mower batteries. LEDs show current charging levels. Double insulated and protected against thermal overload and reverse battery connection." However: "230V. DC. Max. battery size 6Ah. Weight: 1.4kg" ???? Shirley the smallest motor car battery is around 40 Ah? Something does not compute; I assume that the details are wrong. Cheers Dave R P.S. Happy New Year! -- Dell XPS laptop running W8.1 |
#2
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12V battery charger from Screwfix - specifications?
On 1 Jan 2019 11:00:00 GMT, David wrote:
https://www.screwfix.com/p/streetwiz...matic-battery- charger-12v/7752r#product_additional_details_container "12V automatic heavy duty plastic-cased battery charger for car, motorcycle and lawn mower batteries. LEDs show current charging levels. Double insulated and protected against thermal overload and reverse battery connection." However: "230V. DC. Max. battery size 6Ah. Weight: 1.4kg" ???? Shirley the smallest motor car battery is around 40 Ah? Something does not compute; I assume that the details are wrong. The only thing I can see wrong IS that mention of 6Ah with battery power. A 6A it would (eventually) charge even the biggest (good) battery you are likely to find on a conventional (12V) vehicle. The only rider on that would be if it has a timeout, automatically cutting it off before it had fully charged a big battery. Cheers, T i m |
#3
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12V battery charger from Screwfix - specifications?
It happens that David formulated :
However: "230V. DC. Max. battery size 6Ah. Weight: 1.4kg" ???? Shirley the smallest motor car battery is around 40 Ah? Something does not compute; I assume that the details are wrong. I think they have their amps and amp/hours mixed up. The maximum output is 6amps. I would be a little wary of the 'automatic' part of the description, it reads as if it a basic transformer, rectifier with ammeter unit with no automatic control so if left will over-charge a battery. |
#5
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12V battery charger from Screwfix - specifications?
on 01/01/2019, Terry Casey supposed :
As to whether it is really 'automatic' or not, if it isn't, surely that will be a serious offence under the Trade Descriptions Act? I suspect not, it will 'automatically' charge your battery, trouble is it will not stop when fully charged. It looks very much like a conventional old fashioned charger, just the power switch and ammeter. Modern auto-chargers usually have a button to initiate the charge and will refuse to initiate if the polarity is reversed - no sign of that. Personally, I dumped that sort of charger decades ago. |
#6
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12V battery charger from Screwfix - specifications?
On Tuesday, 1 January 2019 11:00:03 UTC, David WE Roberts (Google) wrote:
https://www.screwfix.com/p/streetwiz...matic-battery- charger-12v/7752r#product_additional_details_container "12V automatic heavy duty plastic-cased battery charger for car, motorcycle and lawn mower batteries. LEDs show current charging levels. Double insulated and protected against thermal overload and reverse battery connection." However: "230V. DC. Max. battery size 6Ah. Weight: 1.4kg" ???? Shirley the smallest motor car battery is around 40 Ah? Something does not compute; I assume that the details are wrong. Cheers Dave R P.S. Happy New Year! It looks like a 6A car battery charger. If so the max 6Ah claim is nonsense. NT |
#7
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12V battery charger from Screwfix - specifications?
In article ,
Terry Casey wrote: It seems to be impossible to find a detailed specification for these chargers. I found a document relating to the larger 6/12V switchable 8 & 12A versions but these are only operating instructions. The nearest irt comes to a specification is to state the maximum charge rates but, at least, is does say that the 12A version is suitable bir batteries up to 160 Ah and up to 112 Ah the 8A version so, pro rata, the figure for the 6A one underdiscussion here is likekly to be in the region 0f 75 - 80 Ah. I'll bet those charge figures are a peak output plucked from the air. Makes you wonder how the car alternator can re-charge the battery so quickly if 6 amps is a safe amount into an 80 amp.hr battery which is towards the large size for most cars. I have a Halfords charger - a few years old but claims to be automatic. On the front says 11 amps. It takes longer to charge my car battery than the 14 quid Lidl one which only claims about 4 amps. -- *Venison for dinner again? Oh deer!* Dave Plowman London SW To e-mail, change noise into sound. |
#8
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12V battery charger from Screwfix - specifications?
In article ,
Harry Bloomfield wrote: on 01/01/2019, Terry Casey supposed : As to whether it is really 'automatic' or not, if it isn't, surely that will be a serious offence under the Trade Descriptions Act? I suspect not, it will 'automatically' charge your battery, trouble is it will not stop when fully charged. It looks very much like a conventional old fashioned charger, just the power switch and ammeter. Modern auto-chargers usually have a button to initiate the charge and will refuse to initiate if the polarity is reversed - no sign of that. Personally, I dumped that sort of charger decades ago. All you need to prevent wrong connection is an internal relay with the coil fed via a diode from the battery. That's been a feature of many for a long time. -- *If God had wanted me to touch my toes, he would have put them on my knees Dave Plowman London SW To e-mail, change noise into sound. |
#9
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12V battery charger from Screwfix - specifications?
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#10
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12V battery charger from Screwfix - specifications?
In article , Peter Parry
wrote: On Tue, 1 Jan 2019 17:32:46 -0800 (PST), wrote: It looks like a 6A car battery charger. If so the max 6Ah claim is nonsense. How dare you cast Nasturtiums upon honourable ancestors Chinese descriptions. Search for SWBCG6 brings up a number of sellers and such details as :- "Charge rate: 4.2 Adc equal to 6 Amps RMS" "Suitable Use Type : Suitable for Lead & Acid Batteries" " Ideal For Porsche 911" "Suitable for cars up to 2.5L (2500cc)" "Not suitable for children under 14 years" "Current Type : DC" "Not suitable for trickle charge" "Ideal for Long-Term Connection" It does seem a shame it can't be used on children under 14. but with them it's oftena matter of usingb up energy, rather than adding it. -- from KT24 in Surrey, England "I'd rather die of exhaustion than die of boredom" Thomas Carlyle |
#11
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12V battery charger from Screwfix - specifications?
On Tue, 01 Jan 2019 20:43:00 GMT, Harry Bloomfield
wrote: on 01/01/2019, Terry Casey supposed : As to whether it is really 'automatic' or not, if it isn't, surely that will be a serious offence under the Trade Descriptions Act? I suspect not, it will 'automatically' charge your battery, trouble is it will not stop when fully charged. It looks very much like a conventional old fashioned charger, just the power switch and ammeter. Modern auto-chargers usually have a button to initiate the charge and will refuse to initiate if the polarity is reversed - no sign of that. I have an old 'automatic' Halfords charger that has no buttons to initiate anything and stops (or goes into maintain mode, I can't remember) when the battery is fully charged. Just two rocker switches, one for High / Low (charging current) and one for Sealed / Std. Two LEDS, one amber one for charging and a green for charged. https://s3-eu-west-1.amazonaws.com/cc-ecommerce/product_catalog/0017/16/thumb_1615334_product_catalog_medium.jpeg Personally, I dumped that sort of charger decades ago. Only a few of my modern 'auto-chargers' have a button on them to initiate anything either (Optimate 2,3,4 and 6). https://www.optimate.co.uk/products/optimate-6 I do have a couple of the Lidl Ctek clones but I rarely use them because ICBA to press the button to get them going. ;-) Cheers, T i m |
#12
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12V battery charger from Screwfix - specifications?
On Wed, 02 Jan 2019 10:42:27 +0000 (GMT), "Dave Plowman (News)"
wrote: snip I have a Halfords charger - a few years old but claims to be automatic. On the front says 11 amps. It takes longer to charge my car battery than the 14 quid Lidl one which only claims about 4 amps. But that final time can depend on the time *it* takes to manage the final phase? Like the Optimates go though a charge and leave stage at the end and monitor how much the voltage drops when left. If it drops too much it starts charging again and will only put up the 'Done' LED, once it really is. Therefore, it might appear to take longer than a more basic lower powered charger because it's more thorough? (I'm not saying that IS the case with your chargers etc ...) Cheers, T i m |
#13
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12V battery charger from Screwfix - specifications?
In article ,
T i m wrote: On Wed, 02 Jan 2019 10:42:27 +0000 (GMT), "Dave Plowman (News)" wrote: snip I have a Halfords charger - a few years old but claims to be automatic. On the front says 11 amps. It takes longer to charge my car battery than the 14 quid Lidl one which only claims about 4 amps. But that final time can depend on the time *it* takes to manage the final phase? Quite. I'd guess the Lidl one bashes in its full output 'till fully charged. Unlike the crude Halfords one that works on battery terminal voltage. Like the Optimates go though a charge and leave stage at the end and monitor how much the voltage drops when left. If it drops too much it starts charging again and will only put up the 'Done' LED, once it really is. Therefore, it might appear to take longer than a more basic lower powered charger because it's more thorough? (I'm not saying that IS the case with your chargers etc ...) Basically, the old Rover has quite a high quiescent load on the battery due to a 'sophisticated' alarm and other toys I've added. And the car may not get regular use. So I charge the battery every three weeks, if it's not been used. If one charger was doing a better job of fully charging the battery, I'd guess I'd notice. ;-). -- *I'm not being rude. You're just insignificant Dave Plowman London SW To e-mail, change noise into sound. |
#14
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12V battery charger from Screwfix - specifications?
Dave Plowman (News) brought next idea :
I'll bet those charge figures are a peak output plucked from the air. Makes you wonder how the car alternator can re-charge the battery so quickly if 6 amps is a safe amount into an 80 amp.hr battery which is towards the large size for most cars. Peak of the ac current and only into a large and very flat battery, output will go down drastically as the battery take a charge and builds up some voltage. |
#15
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12V battery charger from Screwfix - specifications?
Dave Plowman (News) wrote on 02/01/2019 :
All you need to prevent wrong connection is an internal relay with the coil fed via a diode from the battery. That's been a feature of many for a long time. I am aware of that thank you, but this charger doesn't not suggest it has any reverse protection. It appears to have just an on/off mains switch and an ammeter. Nothing to indicate the charge is complete, so likely just a transformer and a rectum fryer inside. |
#16
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12V battery charger from Screwfix - specifications?
On Wed, 02 Jan 2019 16:24:58 +0000 (GMT), "Dave Plowman (News)"
wrote: In article , T i m wrote: On Wed, 02 Jan 2019 10:42:27 +0000 (GMT), "Dave Plowman (News)" wrote: snip I have a Halfords charger - a few years old but claims to be automatic. On the front says 11 amps. It takes longer to charge my car battery than the 14 quid Lidl one which only claims about 4 amps. But that final time can depend on the time *it* takes to manage the final phase? Quite. I'd guess the Lidl one bashes in its full output 'till fully charged. I don't know any good (non faulty) LA charger that would work like that, not without the potential to cook (/overgas) the battery that is (depending on the ability of the charger and the capacity of the battery). Even the charger for my EV (200Ah / 48V battery) only gives full output (current) for the bulk charge phase before tapering down to next to nothing. Unlike the crude Halfords one that works on battery terminal voltage. Don't most chargers work that way, even straight transformer / rectifier (taper) ones? Like the Optimates go though a charge and leave stage at the end and monitor how much the voltage drops when left. If it drops too much it starts charging again and will only put up the 'Done' LED, once it really is. Therefore, it might appear to take longer than a more basic lower powered charger because it's more thorough? (I'm not saying that IS the case with your chargers etc ...) Basically, the old Rover has quite a high quiescent load on the battery due to a 'sophisticated' alarm and other toys I've added. And the car may not get regular use. So I charge the battery every three weeks, if it's not been used. If one charger was doing a better job of fully charging the battery, I'd guess I'd notice. ;-). Funnily enough I was talking to a mate tonight about his desire to automatically turn on various battery chargers for (say) 120 mins once every month. He said he couldn't find a 30 day timer (?) so I was thinking of one of the ESP / Arduino's might be handy? Cheers, T i m |
#17
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12V battery charger from Screwfix - specifications?
On Tue, 01 Jan 2019 12:36:58 -0000, Harry Bloomfield wrote:
It happens that David formulated : However: "230V. DC. Max. battery size 6Ah. Weight: 1.4kg" ???? Shirley the smallest motor car battery is around 40 Ah? Something does not compute; I assume that the details are wrong. I think they have their amps and amp/hours mixed up. The maximum output is 6amps. I would be a little wary of the 'automatic' part of the description, it reads as if it a basic transformer, rectifier with ammeter unit with no automatic control so if left will over-charge a battery. Bull****. I've got a very basic 4A battery charger. Just a transformer and rectifier. If the battery is flat, it'll give out 4A. Once the battery gets full, it drops to a fraction of an amp. Basically it just gives out 13.8V maximum - the trickle charge for a lead acid. The battery itself prevents overcharge by taking far less current once it's full. Lead acids are very easy to charge without complicated circuitry. You only need complicated circuitry if you want to charge them really fast. How do you think a car alternator works? It just feeds 14.4V to the battery continuously. Probably a bad idea 24/7, but the car ain't running 24/7. |
#18
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12V battery charger from Screwfix - specifications?
In article ,
Commander Kinsey wrote: Bull****. I've got a very basic 4A battery charger. Just a transformer and rectifier. If the battery is flat, it'll give out 4A. Once the battery gets full, it drops to a fraction of an amp. Basically it just gives out 13.8V maximum - the trickle charge for a lead acid. The output of a basic battery charger will vary a lot due to the transformer regulation and so on. A basic one is very unlikely to produce a constant voltage - unless specifically for SLA gel types. The battery itself prevents overcharge by taking far less current once it's full. Lead acids are very easy to charge without complicated circuitry. You only need complicated circuitry if you want to charge them really fast. How do you think a car alternator works? It just feeds 14.4V to the battery continuously. Probably a bad idea 24/7, but the car ain't running 24/7. No alternator I've ever seen stays at 14.4v when the battery is charged. It would very soon fry the battery. And modern batteries are semi sealed and don't like gassing. I have a very accurate voltmeter fitted to one car, and the volts do go up to over 14 when the battery is low, but the normal figure is not surprisingly 13.8v. It can be a little lower with heavy loads at low engine speeds. -- *Can fat people go skinny-dipping? Dave Plowman London SW To e-mail, change noise into sound. |
#19
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12V battery charger from Screwfix - specifications?
On Fri, 04 Jan 2019 18:17:29 -0000, Dave Plowman (News) wrote:
In article , Commander Kinsey wrote: Bull****. I've got a very basic 4A battery charger. Just a transformer and rectifier. If the battery is flat, it'll give out 4A. Once the battery gets full, it drops to a fraction of an amp. Basically it just gives out 13.8V maximum - the trickle charge for a lead acid. The output of a basic battery charger will vary a lot due to the transformer regulation and so on. A basic one is very unlikely to produce a constant voltage - unless specifically for SLA gel types. I presume the transformer and diodes are chosen so it never goes about about 13.5 volts, which means it'll charge at 4A if the battery really needs a boost, limited by the resistance in the transformer coils, then drop off to virtually no current at around 13.5V once it's full. On my 60Ah car battery, it charges at 4A if I've even just used it slightly (for example put the headlights on for a few minutes with the engine off). If I leave it overnight, it's 0.4A in the morning, and the battery is completely full. The battery itself prevents overcharge by taking far less current once it's full. Lead acids are very easy to charge without complicated circuitry. You only need complicated circuitry if you want to charge them really fast. How do you think a car alternator works? It just feeds 14.4V to the battery continuously. Probably a bad idea 24/7, but the car ain't running 24/7. No alternator I've ever seen stays at 14.4v when the battery is charged. It would very soon fry the battery. And modern batteries are semi sealed and don't like gassing. Maybe modern cars have a regulator to stop that, but older cars (and I mean around the turn of the century ones, not vintage) don't. If you put a meter on the battery when the engine is running, it's always over 14V. I assume batteries don't really mind that as long as it's just for driving time - they'd be upset if you did it 24/7. I have a very accurate voltmeter fitted to one car, and the volts do go up to over 14 when the battery is low, but the normal figure is not surprisingly 13.8v. You've got me interested now, so I'm going to check my 2002 Renault Scenic.... maybe I've never checked the voltage after the car's been running for a bit. This website says a continuous charge should be 12.9 to 14.1V for a full battery: https://www.powerstream.com/SLA.htm The battery is currently fully charged, I was driving it this afternoon, I'll go start it and take readings every 10 minutes.... 14.44V on the battery terminals just after starting, engine idling. 14.22V after 10 minutes (no increase when revving it up). 14.19V after 20 minutes - maybe you're right! Something's making it decide to drop the voltage, although only slightly. I thought a "regulator" on a car alternator was just a set of diodes. However I then connected my old 4A Bradex car battery charger to it with the engine off, and it quickly rose to 14.4V. Maybe I shouldn't be leaving that on overnight.... although if it's only giving out half an amp, which is 1/120th of it's capacity, that can't do any harm? I have noticed that the green float indicator (which I never trust) is now white and the battery is only a year old. I leave the charger connected all night, since the alarm has a habit of draining the battery overnight for no reason, and I can find no way of disconnecting it without dismantling the entire dashboard - they hide them well from theives! It can be a little lower with heavy loads at low engine speeds. What seems to surprise a lot of people is an alternator will rapidly charge a battery at idle engine speed, most people seem to think you have to drive around. Also, when jumpstarting someone else's car, you don't have to start the donor car. The donor car has a good battery, it's therefore capable of starting the other engine just as easily as its own one (unless you have really ****ty thin jump leads that lose voltage - my jump leads are 13mm thick each - I think they were sold as lorry jump leads, rated at 600 amps or something). I didn't get them to conduct better, but so they didn't fall apart with age like Halfords ones do. I've jumpstarted plenty cars with normal jumpleads without starting the donor car first. On that subject, I occasionally hear weird myths about certain BMW or Mercedes cars exploding (the battery I think) when they're jumpstarted - this can't be true unless they use 6 volts or something?! Or more likely some stupid fool connected the black and red wires the wrong way round? |
#20
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12V battery charger from Screwfix - specifications?
On Fri, 04 Jan 2019 18:17:29 -0000, Dave Plowman (News) wrote:
In article , Commander Kinsey wrote: Bull****. I've got a very basic 4A battery charger. Just a transformer and rectifier. If the battery is flat, it'll give out 4A. Once the battery gets full, it drops to a fraction of an amp. Basically it just gives out 13.8V maximum - the trickle charge for a lead acid. The output of a basic battery charger will vary a lot due to the transformer regulation and so on. A basic one is very unlikely to produce a constant voltage - unless specifically for SLA gel types. Just been reading up on Li-Ion car batteries (I assume they have charging protection built into them so they can just be dropped into an existing car). They cost twice as much but should last 4 times as long. They're lighter, so motorcyclists love them, not sure the weight is important in a car though. |
#21
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12V battery charger from Screwfix - specifications?
In article ,
Commander Kinsey wrote: No alternator I've ever seen stays at 14.4v when the battery is charged. It would very soon fry the battery. And modern batteries are semi sealed and don't like gassing. Maybe modern cars have a regulator to stop that, Pretty well all cars - even in dynamo days - have a regulator. In most alternators, it's built in. but older cars (and I mean around the turn of the century ones, not vintage) don't. If you put a meter on the battery when the engine is running, it's always over 14V. I assume batteries don't really mind that as long as it's just for driving time - they'd be upset if you did it 24/7. If you check the battery volts just after a cold start, you'd be right. You need to hook up your meter to show the volts after some time running, when the battery is charged. -- *No word in the English language rhymes with month, orange, silver,purple Dave Plowman London SW To e-mail, change noise into sound. |
#22
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12V battery charger from Screwfix - specifications?
In article ,
Commander Kinsey wrote: On Fri, 04 Jan 2019 18:17:29 -0000, Dave Plowman (News) wrote: In article , Commander Kinsey wrote: Bull****. I've got a very basic 4A battery charger. Just a transformer and rectifier. If the battery is flat, it'll give out 4A. Once the battery gets full, it drops to a fraction of an amp. Basically it just gives out 13.8V maximum - the trickle charge for a lead acid. The output of a basic battery charger will vary a lot due to the transformer regulation and so on. A basic one is very unlikely to produce a constant voltage - unless specifically for SLA gel types. Just been reading up on Li-Ion car batteries (I assume they have charging protection built into them so they can just be dropped into an existing car). They cost twice as much but should last 4 times as long. They're lighter, so motorcyclists love them, not sure the weight is important in a car though. All types of batteries require a different charger. Wet lead acid is popular because it is less critical of the charging routine than other types. Must admit to never having heard of a Li-Ion type being used as a starter battery in a normal car - although I can see why on a bike. But to me, it would make more sense to use an alternator with a regulator and wiring specially designed for the job. Rather than fudge things to make a drop in replacement for a lead acid. -- *Why don't sheep shrink when it rains? Dave Plowman London SW To e-mail, change noise into sound. |
#23
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Troll-feeding Senile IDIOT Alert!
On Sat, 05 Jan 2019 11:47:26 +0000 (GMT), Dave Blowman (News) another
notorious troll-feeding senile idiot, babbled again: If you check the battery volts just after a cold start, you'd be right. You need to hook up your meter to show the volts after some time running, when the battery is charged. HE got YOU on the hook, you troll-feeding senile piece of ****! |
#24
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Troll-feeding Senile IDIOT Alert!
On Sat, 05 Jan 2019 11:54:33 +0000 (GMT), Dave Blowman (News) another
notorious troll-feeding senile idiot, babbled again: But to me, it would make more sense to use an alternator with a regulator and wiring specially designed for the job. To me it would make more sense it you just shut your stupid troll-feeding senile gob, Blowman! |
#25
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Troll-feeding Senile IDIOT Alert!
On Fri, 04 Jan 2019 18:17:29 +0000 (GMT), Dave Blowman (News) another
notorious troll-feeding senile idiot, babbled again: surprisingly 13.8v. It can be a little lower with heavy loads at low engine speeds. I wonder how LOW you can still sink, troll-feeding senile idiot! |
#26
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12V battery charger from Screwfix - specifications?
On Sat, 05 Jan 2019 11:47:26 -0000, Dave Plowman (News) wrote:
In article , Commander Kinsey wrote: No alternator I've ever seen stays at 14.4v when the battery is charged. It would very soon fry the battery. And modern batteries are semi sealed and don't like gassing. Maybe modern cars have a regulator to stop that, Pretty well all cars - even in dynamo days - have a regulator. In most alternators, it's built in. I've heard the term "regulator" used for cars, but I thought it was to change 3 phase AC into DC, just a big bridge rectifier. but older cars (and I mean around the turn of the century ones, not vintage) don't. If you put a meter on the battery when the engine is running, it's always over 14V. I assume batteries don't really mind that as long as it's just for driving time - they'd be upset if you did it 24/7. If you check the battery volts just after a cold start, you'd be right. You need to hook up your meter to show the volts after some time running, when the battery is charged. I wasn't aware lead acids were so fragile. I have my old car connected to an old Bradex 4A charger 24/7, as the alarm runs the battery flat. The charger indicates it's delivering 0.5 amps after it's been sat for a while, and I've measured it at 14.4V. Surely charging a 60Ah battery at 0.5A (which is a 5 day charge!) can't possibly break it? |
#27
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12V battery charger from Screwfix - specifications?
On Sat, 05 Jan 2019 11:54:33 -0000, Dave Plowman (News) wrote:
In article , Commander Kinsey wrote: On Fri, 04 Jan 2019 18:17:29 -0000, Dave Plowman (News) wrote: In article , Commander Kinsey wrote: Bull****. I've got a very basic 4A battery charger. Just a transformer and rectifier. If the battery is flat, it'll give out 4A. Once the battery gets full, it drops to a fraction of an amp. Basically it just gives out 13.8V maximum - the trickle charge for a lead acid. The output of a basic battery charger will vary a lot due to the transformer regulation and so on. A basic one is very unlikely to produce a constant voltage - unless specifically for SLA gel types. Just been reading up on Li-Ion car batteries (I assume they have charging protection built into them so they can just be dropped into an existing car). They cost twice as much but should last 4 times as long. They're lighter, so motorcyclists love them, not sure the weight is important in a car though. All types of batteries require a different charger. Wet lead acid is popular because it is less critical of the charging routine than other types. Must admit to never having heard of a Li-Ion type being used as a starter battery in a normal car - although I can see why on a bike. But to me, it would make more sense to use an alternator with a regulator and wiring specially designed for the job. Rather than fudge things to make a drop in replacement for a lead acid. You can buy Li-ion drop in replacements made by the likes of Bosch on Eurocarparts. I assume it simply stops or restricts the charging current internal to the battery when it's had enough, easy enough to do that with a very cheap chip compared to the cost of the whole battery. It's smaller and lighter than lead acid, but who cares in a car. The reason I'd buy one (and I will next time I need a new battery) is they cost twice as much but last 5 times longer. Plus if the alternator overcharges it, it can't, as the battery looks after itself. Plus, apparently they aren't so bothered about deep discharge as lead acids, either due to the chemistry or due to some internal protection circuit. |
#28
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12V battery charger from Screwfix - specifications?
In article ,
Commander Kinsey wrote: On Sat, 05 Jan 2019 11:47:26 -0000, Dave Plowman (News) wrote: In article , Commander Kinsey wrote: No alternator I've ever seen stays at 14.4v when the battery is charged. It would very soon fry the battery. And modern batteries are semi sealed and don't like gassing. Maybe modern cars have a regulator to stop that, Pretty well all cars - even in dynamo days - have a regulator. In most alternators, it's built in. I've heard the term "regulator" used for cars, but I thought it was to change 3 phase AC into DC, just a big bridge rectifier. They have both. Rectifier pack and regulator. Some older - or larger alternators - had the regulator external to the alternator. but older cars (and I mean around the turn of the century ones, not vintage) don't. If you put a meter on the battery when the engine is running, it's always over 14V. I assume batteries don't really mind that as long as it's just for driving time - they'd be upset if you did it 24/7. If you check the battery volts just after a cold start, you'd be right. You need to hook up your meter to show the volts after some time running, when the battery is charged. I wasn't aware lead acids were so fragile. I have my old car connected to an old Bradex 4A charger 24/7, as the alarm runs the battery flat. The charger indicates it's delivering 0.5 amps after it's been sat for a while, and I've measured it at 14.4V. Surely charging a 60Ah battery at 0.5A (which is a 5 day charge!) can't possibly break it? Something very odd indeed if you're seeing 14.4 volts and an 0.5 amp charge at the same time. -- *I'm already visualizing the duct tape over your mouth Dave Plowman London SW To e-mail, change noise into sound. |
#29
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12V battery charger from Screwfix - specifications?
On Sat, 05 Jan 2019 15:43:57 -0000, Dave Plowman (News) wrote:
In article , Commander Kinsey wrote: On Sat, 05 Jan 2019 11:47:26 -0000, Dave Plowman (News) wrote: In article , Commander Kinsey wrote: No alternator I've ever seen stays at 14.4v when the battery is charged. It would very soon fry the battery. And modern batteries are semi sealed and don't like gassing. Maybe modern cars have a regulator to stop that, Pretty well all cars - even in dynamo days - have a regulator. In most alternators, it's built in. I've heard the term "regulator" used for cars, but I thought it was to change 3 phase AC into DC, just a big bridge rectifier. They have both. Rectifier pack and regulator. Some older - or larger alternators - had the regulator external to the alternator. So it has some kind of intelligent sensor that detects when the battery is full and switches to trickle mode? but older cars (and I mean around the turn of the century ones, not vintage) don't. If you put a meter on the battery when the engine is running, it's always over 14V. I assume batteries don't really mind that as long as it's just for driving time - they'd be upset if you did it 24/7. If you check the battery volts just after a cold start, you'd be right. You need to hook up your meter to show the volts after some time running, when the battery is charged. I wasn't aware lead acids were so fragile. I have my old car connected to an old Bradex 4A charger 24/7, as the alarm runs the battery flat. The charger indicates it's delivering 0.5 amps after it's been sat for a while, and I've measured it at 14.4V. Surely charging a 60Ah battery at 0.5A (which is a 5 day charge!) can't possibly break it? Something very odd indeed if you're seeing 14.4 volts and an 0.5 amp charge at the same time. What would you expect to see? The above is my experience with all lead acids, they simply don't take much current when they're full. |
#30
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12V battery charger from Screwfix - specifications?
In article ,
Commander Kinsey wrote: You can buy Li-ion drop in replacements made by the likes of Bosch on Eurocarparts. Just been through their entire range. Plenty of Lion brand batteries, but no mention at all of Li-Ion. Can you give a part number? -- *Funny, I don't remember being absent minded. Dave Plowman London SW To e-mail, change noise into sound. |
#31
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12V battery charger from Screwfix - specifications?
On Sat, 05 Jan 2019 16:08:55 -0000, Dave Plowman (News) wrote:
In article , Commander Kinsey wrote: You can buy Li-ion drop in replacements made by the likes of Bosch on Eurocarparts. Just been through their entire range. Plenty of Lion brand batteries, Yip, I've got one of those in my car. When I looked up reviews, everybody was confusing them with Lithium Ion! but no mention at all of Li-Ion. Can you give a part number? Ok I dunno what's going on here. Yesterday I found the Bosch battery on Eurocarparts by doing a Google search for "Lithium Ion car battery". Now I'm seeing an actual lead acid Bosch. I was sure it said Lithium Ion, and at over £2 per Ah, I assumed it had to be! Lead Acids are about 60p an Ah - I bought my lead acid Lion car battery for £40, and it's 60Ah (and I tested it to make sure). Now all I can see is this 5Ah (although you get more usable capacity with Li-Ion, lead acids don't like deep discharge) Lithium Ion for £77 on Ebay: http://www.ebay.co.uk/itm/362524512734 Or 20Ah for £200: http://www.ebay.co.uk/itm/273372798039 At that price, forget it! I'll use lead acid. 17 times the cost for something that lasts 5 times longer, no. I also don't like the way they state "up to 2000 charge cycles" - I was under the impression lead acid was up to 1000 and Li-Ion was up to 5000. That makes them even more pointless, unless you absolutely want to save weight on a motorcycle or a racing car. Weird they're that expensive, as I've got a mobile phone sized 20Ah (I haven't validated that claim!) Li-Ion jump starter pack which was only £20. Perhaps it's no good for continuous use in a car though. I can start the car with it, and it's handy as a USB power source to run phones, satnavs, cameras, etc, etc from when camping. They're made of 3 pouch shaped cells, Bigclive did a teardown on Youtube: https://youtu.be/0tGK1nqXr28 |
#32
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12V battery charger from Screwfix - specifications?
On Saturday, 5 January 2019 15:23:19 UTC, Commander Kinsey wrote:
I wasn't aware lead acids were so fragile. I have my old car connected to an old Bradex 4A charger 24/7, as the alarm runs the battery flat. The charger indicates it's delivering 0.5 amps after it's been sat for a while, and I've measured it at 14.4V. Surely charging a 60Ah battery at 0.5A (which is a 5 day charge!) can't possibly break it? Unregulated chargers have killed many batteries when left on too long. NT |
#33
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12V battery charger from Screwfix - specifications?
On Sat, 05 Jan 2019 18:31:01 -0000, wrote:
On Saturday, 5 January 2019 15:23:19 UTC, Commander Kinsey wrote: I wasn't aware lead acids were so fragile. I have my old car connected to an old Bradex 4A charger 24/7, as the alarm runs the battery flat. The charger indicates it's delivering 0.5 amps after it's been sat for a while, and I've measured it at 14.4V. Surely charging a 60Ah battery at 0.5A (which is a 5 day charge!) can't possibly break it? Unregulated chargers have killed many batteries when left on too long. I'm not so sure lead acids are that fussy. Everybody tells me you must never flatten one, yet I've had a battery which I let run completely flat about 20 times, and it still works fine. And I don't believe overcharging it at a 5 day charge rate could kill it. Oh well, if it breaks it breaks, I've loads of batteries kicking about. I'll buy a nicer charger if it dies. I was going to get a Li-Ion battery if it died (they'd have their own charge protection), but since those cost WAY more than I thought, I won't bother. |
#34
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Troll-feeding Senile IDIOT Alert!
On Sat, 05 Jan 2019 15:43:57 +0000 (GMT), Dave Blowman (News) another
notorious troll-feeding senile idiot, babbled again: Something very odd indeed if you're seeing 14.4 volts and an 0.5 amp charge at the same time. What could be odder than seeing you two prize idiots (a trolling idiot and his corresponding troll-feeding senile idiot) having a "conversation"! LOL |
#35
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Troll-feeding Senile IDIOT Alert!
On Sat, 05 Jan 2019 16:08:55 +0000 (GMT), Dave Blowman (News) another
notorious troll-feeding senile idiot, babbled again: Just been through their entire range. Plenty of Lion brand batteries, but no mention at all of Li-Ion. Can you give a part number? He can set out yet another idiotic bait for you, senile idiot! BG |
#36
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Troll-feeding Senile IDIOT Alert!
On Sat, 5 Jan 2019 10:31:01 -0800 (PST), , an especially
retarded, troll-feeding, senile idiot, blathered: Unregulated chargers have killed many batteries when left on too long. NT You just CAN'T resist the unwashed Scottish ******'s cock, can you, senile idiot? LOL Just wait what kind of "replies" you will get from the ****** again! LMAO! |
#37
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12V battery charger from Screwfix - specifications?
In article ,
Commander Kinsey wrote: On Sat, 05 Jan 2019 18:31:01 -0000, wrote: On Saturday, 5 January 2019 15:23:19 UTC, Commander Kinsey wrote: I wasn't aware lead acids were so fragile. I have my old car connected to an old Bradex 4A charger 24/7, as the alarm runs the battery flat. The charger indicates it's delivering 0.5 amps after it's been sat for a while, and I've measured it at 14.4V. Surely charging a 60Ah battery at 0.5A (which is a 5 day charge!) can't possibly break it? Unregulated chargers have killed many batteries when left on too long. I'm not so sure lead acids are that fussy. Everybody tells me you must never flatten one, yet I've had a battery which I let run completely flat about 20 times, and it still works fine. And I don't believe overcharging it at a 5 day charge rate could kill it. Oh well, if it breaks it breaks, I've loads of batteries kicking about. I'll buy a nicer charger if it dies. I was going to get a Li-Ion battery if it died (they'd have their own charge protection), but since those cost WAY more than I thought, I won't bother. The little Lidl/Aldi charger at about 14 quid - similar to Ctek at several times the price - changes to a maintenance mode when the battery is fully charged and can be left like that indefinitely. Very simple to do these days with electronics. I'd be most surprised if Li-Ion was worth it for a car starter battery. A decent lead acid should do 10 years plus of normal use. Any weight saving hardly worth the considerable extra cost. I don't think even Rolls Royce fit Li-Ion. -- *A journey of a thousand sites begins with a single click * Dave Plowman London SW To e-mail, change noise into sound. |
#38
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12V battery charger from Screwfix - specifications?
On Mon, 07 Jan 2019 00:50:07 -0000, Dave Plowman (News) wrote:
In article , Commander Kinsey wrote: On Sat, 05 Jan 2019 18:31:01 -0000, wrote: On Saturday, 5 January 2019 15:23:19 UTC, Commander Kinsey wrote: I wasn't aware lead acids were so fragile. I have my old car connected to an old Bradex 4A charger 24/7, as the alarm runs the battery flat. The charger indicates it's delivering 0.5 amps after it's been sat for a while, and I've measured it at 14.4V. Surely charging a 60Ah battery at 0.5A (which is a 5 day charge!) can't possibly break it? Unregulated chargers have killed many batteries when left on too long. I'm not so sure lead acids are that fussy. Everybody tells me you must never flatten one, yet I've had a battery which I let run completely flat about 20 times, and it still works fine. And I don't believe overcharging it at a 5 day charge rate could kill it. Oh well, if it breaks it breaks, I've loads of batteries kicking about. I'll buy a nicer charger if it dies. I was going to get a Li-Ion battery if it died (they'd have their own charge protection), but since those cost WAY more than I thought, I won't bother. The little Lidl/Aldi charger at about 14 quid - similar to Ctek at several times the price - changes to a maintenance mode when the battery is fully charged and can be left like that indefinitely. Very simple to do these days with electronics. I'd be most surprised if Li-Ion was worth it for a car starter battery. A decent lead acid should do 10 years plus of normal use. Any weight saving hardly worth the considerable extra cost. I don't think even Rolls Royce fit Li-Ion. I guess we'll get them when the cost comes down. Which it'll have to do if electric cars are to become viable. But er.... then we won't have starter batteries :-) |
#39
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12V battery charger from Screwfix - specifications?
On 07/01/2019 01:17, Commander Kinsey wrote:
On Mon, 07 Jan 2019 00:50:07 -0000, Dave Plowman (News) wrote: In article , ** Commander Kinsey wrote: On Sat, 05 Jan 2019 18:31:01 -0000, wrote: On Saturday, 5 January 2019 15:23:19 UTC, Commander Kinsey* wrote: I wasn't aware lead acids were so fragile.* I have my old car connected to an old Bradex 4A charger 24/7, as the alarm runs the battery flat.* The charger indicates it's delivering 0.5 amps after it's been sat for a while, and I've measured it at 14.4V.* Surely charging a 60Ah battery at 0.5A (which is a 5 day charge!) can't possibly break it? Unregulated chargers have killed many batteries when left on too long. I'm not so sure lead acids are that fussy.* Everybody tells me you must never flatten one, yet I've had a battery which I let run completely flat about 20 times, and it still works fine.* And I don't believe overcharging it at a 5 day charge rate could kill it.* Oh well, if it breaks it breaks, I've loads of batteries kicking about.* I'll buy a nicer charger if it dies.* I was going to get a Li-Ion battery if it died (they'd have their own charge protection), but since those cost WAY more than I thought, I won't bother. The little Lidl/Aldi charger at about 14 quid - similar to Ctek at several times the price - changes to a maintenance mode when the battery is fully charged and can be left like that indefinitely. Very simple to do these days with electronics. I'd be most surprised if Li-Ion was worth it for a car starter battery. A decent lead acid should do 10 years plus of normal use. Any weight saving hardly worth the considerable extra cost. I don't think even Rolls Royce fit Li-Ion. I guess we'll get them when the cost comes down.* Which it'll have to do if electric cars are to become viable.* But er.... then we won't have starter batteries :-) Seem quite popular for Motor Cycles, but I can't think why.... http://www.fastbikegear.co.nz/index....d=18&chapter=1 Dave |
#40
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Troll-feeding Senile IDIOT Alert!
On Mon, 07 Jan 2019 00:50:07 +0000 (GMT), Dave Blowman (News) another
notorious troll-feeding senile idiot, babbled again: I don't think Indeed, troll-feeding senile idiot! |
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