Mains Charger For Leisure Battery Advice Please!

[mac74]

A broken record i am, but if we keep it to ONE battery then, so i reckon i take out at least 40amp, twice per week, @ say 40 weeks per year = 80 cycles in one year. So if i am learning this right, if ive taken the capacity down to about 65% each time? which is slightly less drain than the 50% max stated by yuasa @ 80 cycles per year. This would mean i got 160 cycles over two years @ 65% ish drain, before the performance drop off, in year three? This would make the whole battery and charger setup ideal wouldn't it? Plus the over charging on it for the first 10 minutes of driving time (split chrg relay) when ive just put the battery in fully charged from mains, and then the drive charge on top, which would also have a negative effect on it, OR would this help put a little extra volts in that the ctek 5ah isn't allan? ( But im now thinking of not connecting the new battery up until i arrive on site, to avoid over cooking it ) So looking at it now, ive not done to badly on the life of them have i ? or am i missing something??? Thank you all for your help and advice on this, mainly allan, keith, & its been educational to me.

 

Best Regards All

 

Malcolm

[spirou]

I would argue the 10min drive is entirely irrelevant in the charging equasion.

[aandncaravan]

mac74 - 2019-03-29 7:36 PM

 

A broken record i am, but if we keep it to ONE battery then, so i reckon i take out at least 40amp, twice per week, @ say 40 weeks per year = 80 cycles in one year. So if i am learning this right, if ive taken the capacity down to about 65% each time? which is slightly less drain than the 50% max stated by yuasa @ 80 cycles per year. This would mean i got 160 cycles over two years @ 65% ish drain, before the performance drop off, in year three? This would make the whole battery and charger setup ideal wouldn't it? Plus the over charging on it for the first 10 minutes of driving time (split chrg relay) when ive just put the battery in fully charged from mains, and then the drive charge on top, which would also have a negative effect on it, OR would this help put a little extra volts in that the ctek 5ah isn't allan? ( But im now thinking of not connecting the new battery up until i arrive on site, to avoid over cooking it ) So looking at it now, ive not done to badly on the life of them have i ? or am i missing something??? Thank you all for your help and advice on this, mainly allan, keith, & its been educational to me.

 

Best Regards All

 

Malcolm

 

 

10amps seems a lot of power for a pump to me, so lets go back to the start?

 

Looking up the Shureflow 100PSI pump, it seems to be rated at 8amps MAX.

With a Power controller fitted, which I think you have, it draws a lot less.

One Forum post measured a 'Power Controller' Shureflow 100PSI pumps continuous current at 1,7amps and he was a 'senior' forum member, not a newbie.

 

Another writes -

"The ampage draw or current will vary unless you are running the pump at 100% all the time it will never draw the full 8amp maximum. With a controller the current used is significantly reduced perhaps a maximum of 4amps?".

 

 

So if we assume that between 2 - 4 amps is typical, then it would seem your 40amps per week is not realistic. Lets choose a mid point of 3 amps.

 

You talk about "a 2 hr solid draw over say 3hrs off/on" x 3 amps = about 6 amps a day from a 115Ah battery = around a 5% Depth Of Discharge (DOD), twice a week for 40 weeks usage and they achieved a poor 160 cycles.

 

I would have expected closer to 1,000 cycles on such shallow depth of discharge on such a quality battery?

Even if the figures are out 50%, 160 cycles isn't good.

 

So I maintain the set-up is not optimal, however only you know the real current draw per day/week, so can only suggest you trust your own judgement.

 

 

 

 

[Keithl]

aandncaravan - 2019-03-30 9:51 PM

 

So I maintain the set-up is not optimal, however only you know the real current draw per day/week, so can only suggest you trust your own judgement.

 

 

Allan,

 

Did you once post a link(?) to a 'device' that measured the current flow and gave a daily 'tally' of usage? If so would it be worth Malcolm investing in one to monitor his actual usage? Then he would know exactly what challenge his battery charger was facing.

 

Found it! A 'Wattmeter' on this page of your website http://www.aandncaravanservices.co.uk/solar-power.php

 

Keith.

[Derek Uzzell]

Rather than try to approach Malcolm’s original question ‘mathematically’, it might be simpler to look at what he might realistically do to maximise the lifespan of his two new Yuasa L36-EFB batteries.

 

If the two Yuasa L35-115 batteries lasted for a significantly shorter period than the data Malcolm provided (equipment used, usage and charging pattern) suggest the period should be, what can he do to improve matters?

 

There’s no suggestion that he is going to change the equipment (pump + controller) nor how he does the window cleaning, and no obvious alternative to the ‘rotation’ method he has employed to charge the batteries. That leaves his CTEK MXS 5.0 battery-charger that has a performance that can be considered borderline for how Malcolm uses it.

 

I would have thought that - to maximise the lifespan of the new batteries - even if the CTEK 5A charger were able to continue to handle the ‘rotation’ charging procedure indefinitely, Malcolm should still consider obtaining a more powerful charger that could charge his batteries faster and more efficiently. His profession demands that he have a well-charged battery at the start of each working-day, and (presumably) this currently makes him reliant on the CTEK charger. Getting another ‘superior’ charger should allow better charginig of Malcolm’s new batteries and the CTEK 5A charger could be kept as a back-up.

 

Which comes back to the last sentence of my posting of 29 March 2019 9:18 AM above where I asked "If it’s believed that buying a different battery-charger would provide genuine value-for-money benefits, then which charger should he buy and what would the cost be?”

[aandncaravan]

Keith, perfect idea and at only £7 it won't break the bank.

 

 

Derek, Agreed.

If you look on the 'window Cleaning forums' and general info sites there is a real issue with masses of misinformation, and I suspect many are not giving the batteries the charging they need.

A bigger charger isn't just about faster charging, it's about having the power to get in that last 20%.

 

 

As I said earlier in the thread, "the lowest spec Motorhome charger we would recommend would be a Sargent PX300 21a charger and they are about £120".

 

Most of the chargers at lower prices are either car battery based chargers or fixed voltage power supplies designed for caravans.

 

A lot of the misinformation and confusion in our sector seems to be deliberately generated by the manufacturers and retailers.

Take the Sargent 'Supercharge' 151. It has got to be one of the most laughable names for a device on the Planet. How can an 8amp, once it gets warm and just 13.5v power supply, be called a 'charger' by the manufacturer?

The manufacturers web site states "The Supercharge 151 is a 150W battery charger / converter" yet not one decent battery manufacturer would say it is even half suitable for fully charging even a small Leisure battery.

 

I think from now on in we will refer to it as the Sargent 'Under Charge' 151.

 

 

 

 

 

 

[Keithl]

aandncaravan - 2019-03-31 11:00 AM

 

Keith, perfect idea and at only £7 it won't break the bank.

 

 

Malcolm,

 

So the suggestion is to spend £7 - 8 pounds on a Wattmeter and measure your actual usage over a full day then see what you are taking out of your batteries every day and then you will be far more informed as to how they need recharging.

 

Keith.

[mac74]

A Wattmeter it is! (great idea keith) does anyone know where i can get one please (link)?, does it just clip onto the battery? Then after we know the actual usage im doing, then maybe the sargent PX300 charger is the next step allan, if it does push the last 20% of charge further than my ctek 5.0 does. This final 20% charging stage you mention allan, is the whole reason i started this tread, and originally what made me question the ability of my ctek msx 5.0ah charger in the first place, having read one of your back posts that i came across before i started this. Q. If my battery is 12.8v when fully charged with my ctek, has it not got the full charge (last 20%)? this is what i need to understand, please explain why allan.

 

 

Thank you all. M

[Keithl]

A quick eBay search gives the cheapest as direct from China for £6.64...

 

https://www.ebay.co.uk/itm/Digital-Monitor-LCD-Watt-Meter-60V-100A-DC-Ammeter-RC-Battery-Power-Amp-Analyzer/352603854530

 

up to £7.39 which appears to be posted in the UK (but do check!)...

 

https://www.ebay.co.uk/itm/Simple-DC-Power-Analyser-Watt-Volt-Amp-Meter-12v-24v-Solar-Wind-Analyzer-Ammeter/312550863708

 

And lots and lots and lots more!

 

Keith.

[mac74]

Keithl - 2019-03-31 8:19 PM

 

A quick eBay search gives the cheapest as direct from China for £6.64...

 

https://www.ebay.co.uk/itm/Digital-Monitor-LCD-Watt-Meter-60V-100A-DC-Ammeter-RC-Battery-Power-Amp-Analyzer/352603854530

 

up to £7.39 which appears to be posted in the UK (but do check!)...

 

https://www.ebay.co.uk/itm/Simple-DC-Power-Analyser-Watt-Volt-Amp-Meter-12v-24v-Solar-Wind-Analyzer-Ammeter/312550863708

 

And lots and lots and lots more!

 

 

 

Keith.

 

Ive just had a look keith, how would i hook that up? would i have to power this meter from another source (say van batt) then onto leisure batt? thanks m

[Keithl]

No, I believe it simply wires in immediately between your battery and pump. Both positive and negative have to go through the meter.

 

Battery - Meter - Switch - Pump

 

Or something like that. Obviously 'Source' is your battery and 'Load' is your pump.

 

Keith.

[aandncaravan]

The wattmeter we recommend fits between the battery and all it's loads, or between the charger and the battery.

 

If fitted between the battery and the 'loads' (Pump) then it will measure all the current taken by the pump in a day. It could actually measure a longer time frame, but as soon as you disconnect the battery the data will be lost and it will reset to zero.

 

 

If fitted between the charger and the battery it measures the charge the CTEK puts into the battery. Note that batteries are not 100% efficient so you may have to put 115Ah in to a 100Ah to be able to draw out 100Ah.

Your new Yuasa's are very efficient, so may need the equivalent of 107Ah to draw out 100Ah, but an older technology or tired battery may need upto 130Ah charge to be able to give only 95Ah back, if that makes sense?

 

 

As for the last 20% and State Of Charge (SOC)?

This is something I have never fully understood as a Wet Acid new battery usually arrives with only about 80% Capacity. It may have been on charge for days, yet the battery capacity is only about 80% of it's rated Ah capacity. See attached graph.

But if you sample the battery voltage, the SOC will indicate a voltage of a 100% capacity battery, even though it is actually only 80%.

 

The same applies when the battery wears out. You stated that your batteries towards EOL would - "charge fully" from flat in 4 hours.

That equates to just 20Ah from a 5.0 amp charger, yet the CTEK showed them as at 'full charge' and the SOC indicated 100% capacity, yet they would deliver only a handful of Ah the next day.

 

I think the SOC only indicates the capacity percentage value of what is left. In your case your batteries were so poor at the end that all that remained of 'active paste' in the Plates was 20Ah of the original 115Ah.

That was why I concluded they had become exhausted months earlier.

 

I would suggest that your 12.8v was indicating that 100% of the remaining 20Ah capacity was available for use.

 

Usually such a battery voltage dives like a Kestrel if any load is put on the battery as taking out just 5Ah results in a drop down to 25% DOD and then drawing another 5Ah results in taking the battery down to 50% of all it can deliver, etc.

 

As I say, I don't know.

 

 

You said you want to learn, so I will go on, sorry to those who have already fallen asleep.

What I do know is, just as your batteries have demonstrated, a battery loses a little bit of Active material from the Plates each time it is discharged resulting in a battery that slowly loses capacity.

When the battery capacity drops below 80%, the industry regard the battery as expired, but people are not aware of loss of capacity so go on using the battery.

 

Eventually the battery has so little capacity you can't help but notice. On lesser batteries than your Yuasa's, the plates additionally start to break up giving Plate shorts and other structural failures and the battery then suffers a full mechanical failure.

 

Someone once wrote that Leisure batteries don't die, they are murdered.

 

 

That you were able take your L35's all the way down to 20% of the original 115Ah capacity without suffering any structural Plate issues that affected things like Fast Self Discharging, etc shows just how well made the Yuasa's are.

Budget batteries would have caused carnage to the charging systems at probably less than 50% loss of capacity.

 

For more info on how to fit the wattmeter, visit the web page that Keith sent you a link to.

 

 

 

 

 

 

 

 

 

[mac74]

Sorry i should have mentioned the reason why i came to the 10amp draw rate, is because i decided to run two shurflo pumps (16ah max) & two spring flow controllers, into one outlet in hope to solve the flow problem? which it did seem to do for a little while? How would i connect this meter up? My setup: Battery to 2 controllers then 2 pumps setup?

At present the set up is, (from instructions) battery power to controllers, then the controllers wire into pumps, i.e - the controllers tell the pumps what to do given the voltage in, so when the batt gets low, the controller tries to protect the batt from low voltage damage, and it also stops the pump going to pressure switch off all the time. But its very handy to press the battery use button on each controller whilst pumps in use, or when stopped, just to cross check if they are both telling the truth on the batt voltage, plus they also adjust the flow rate, which i have at about 80 out of 99 on each, as the pumps are getting old now @ 4yrs, but even when new i run at 70ish flow rate.

Thanks M

[Keithl]

mac74 - 2019-04-01 12:08 AM

...How would i connect this meter up? My setup: Battery to 2 controllers then 2 pumps setup?

 

Thanks M

 

The WattMeter needs to be connected immediately after the batteries, before your controllers.

 

As I tried to visualise above...

 

Battery - Meter - Controller(s) - Pump(s)

 

Keith.

 

PS Now you have a decent battery again have you tried running only one pump again?

[mac74]

I connected the new batt up, and the controllers read 12.6v, then when under draw (1 pump) took the volts down to 11.8v? Im now going to change all wiring and connections next week to 2.5mm thickness instead of the 1.5mm that i fitted 3 years back. Plus i will use as little wire to each unit as poss, as ive got a little excess wiring lengths attached that i dont need, (which may slightly lower the volts the longer wire distance travelled) & see what happens, if no improvement i will change my v9 flow controllers after 7 years to the new v11 type. thanks m

[aandncaravan]

Malcolm, the batteries won't arrive fully charged, can be as low as 75%, so suggest you charge them overnight if you can before you use them.

[mac74]

aandncaravan - 2019-04-01 9:14 PM

 

Malcolm, the batteries won't arrive fully charged, can be as low as 75%, so suggest you charge them overnight if you can before you use them.

 

I did put them both on charge when i got them to top them up (8hrs each). If i do need to change my ctek msx 5.0 charger? I like the look of the victron smart IP65 10amp charger with the iphone use, and as ive read from somewhere before, i think you say that you have never found a ctek charger, to ever charge a battery to anymore than 85% of its 100% capacity? and this is whats bugging me. BUT the real question is: Do you think this victron IP65 10amp charger, is more capable of charging a 100ah leisure battery, nearer to its 100% capacity, THAN my ctek msx 5.0amp can do, OR even the msx 10amp can do????

 

Many Thanks to ALL

[Derek Uzzell]

If you decide on a Victron BluePower charger, you might want to opt for the 15A version as there’s evidently not a huge step-up in the asking-price between the 10A and 15A chargers.

 

http://tinyurl.com/y4w9p8le

 

What Allan said earlier in this discussion was

 

Most of the smaller CTEK's we have seen are Car battery chargers, for occasionally use, not designed to charge a big battery every day.

 

and

 

Victron are giants in the battery and charger world, have a look at their approach to Sulphation, etc.

 

Sorry but we have opened too many CTEK chargers to be impressed. In my view overpriced and underperforming compared to the competition, but very clever marketing.

 

Realistically, you have two options

 

1: Spend nothing and continue to rely on your CTEK MXS 5.0 5A charger (that is marginal and probably not optimum) for the task of charging the two Yuasa 100Ah batteries that you’ll be rotating daily.

 

2: Invest cash in a more powerful device that would charge your batteries faster and more efficiently, and would allow you to keep the CTEK charger as a back-up.

 

You can collect data and theorise till the cows come home, but Allan clearly likes the Victron brand (and doesn’t like CTEK) so purchasing a Victron charger makes good sense. And, if a Victron 10A charger costs £125 and the 15A version costs just £19 more, choosing the 15A Victron would seem the logical thing to do.

[mac74]

I have ordered the watt meter, and im looking at the victron range as i like the phone thing it does, derek what would the 15amp one give me over the 10amp, is it JUST a faster charge (which i dont need), and do you think these chargers will fill to a higher capacity than the my ctek does? im hoping alan comes back in on this please, we are almost done i promise! In a shoot out between the sargent PX300 21a v victron blue range, pros & cons before i order one, ANYONE? Many Thanks m

[mac74]

Hello all, i have finally decided to go for the - Victron Energy Blue Smart IP65 15amp Charger - I hope this will give my 2 new yuasa L36-EFB 100ah batts a longer life than my current ctek 5amp charger? time will tell i guess. Going to order it tomorrow, cheapest ive found is ebay @ £137 ish delivered, from battery megastore, i just want to check its a connect and forget type. Sorry ive been going on about this for a while, (allan has probably still got his head in his hands) but genuinely many thanks to all, for your input on it, as its been really helpful to me.

 

Best Regards To All

 

Malcolm

[spirou]

Seems it comes with clamps and M8 eyelets as standard and many other add-ons as options:

https://www.victronenergy.com/upload/documents/Folder-Blue-Smart-IP65-charger-230V-EN_web.pdf

 

The phone/computer app gives you a lot of options to track data and modify parameters as needed.

[mac74]

Just ordered the Victron Energy Blue Smart IP65 Charger 12v 15amp 230V - BPC121531024R, (£136ish battery megastore via ebay) will get it tomorrow. Im now glad ive done this due to all the advice on here (thanks), because yesterday after i put in a fresh 100ah efb battery for work it dropped down to 12.4/5v almost straight away, which may indicate that its true that my ctek 5amp charger wasn't taking it upto full capacity? I will also change all my 1.5m wiring next week to 2.5mm 13awg (from batt - controllers - pumps) keeping the lengths as short as possible, and fit the watt meters between the batt to the controllers too. Thanks All, m.

[spirou]

mac74 - 2019-04-04 4:56 PM

I will also change all my 1.5m wiring next week to 2.5mm 13awg (from batt - controllers - pumps) keeping the lengths as short as possible, and fit the watt meters between the batt to the controllers too. Thanks All, m.

 

Is this 12V or 230V running through 1.5mm2 wire? In a 12V system and your kind of current load I would expect something like 10mm2 wire.

[mac74]

spirou - 2019-04-04 7:00 PM

 

mac74 - 2019-04-04 4:56 PM

I will also change all my 1.5m wiring next week to 2.5mm 13awg (from batt - controllers - pumps) keeping the lengths as short as possible, and fit the watt meters between the batt to the controllers too. Thanks All, m.

 

Is this 12V or 230V running through 1.5mm2 wire? In a 12V system and your kind of current load I would expect something like 10mm2 wire.

Its 12v, but i only draw around 10amps on my pumps, the 1.5mm is standard, but ive gone thicker so i dont lose power. cheers m

[Derek Uzzell]

There’s a Voltage Drop Calculator here

 

https://www.12voltplanet.co.uk/cable-sizing-selection.html

 

As an example, for a supply voltage of 12V, 10A current draw, a 3metre cable length and a cable-size of 1.5mm2, a voltage drop of 0.68 (5.67% of supply voltage) is given. Using a 2.5mm2 cable-size gives a voltage drop of 0.41 (3.42% of supply voltage). Using a 10.0mm2 cable-size gives a voltage drop of 0.10 (0.83% of supply voltage). I’ve no idea what cable-lengths you have, but if you are going to replace the present 1.5mm2 cables, 2.5mm2 would still be a bit skimpy.