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AGM Battery charging


weldted

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2019 Burstner, two 95 amp AGM batteries, 18 amp mains charger, one 100 watt solar panel. When on hook (just plugged in) batteries were reading 85% rate of charge showed 3.5 amps. Yesterday’s run of around 120 miles, at start of run batteries state of charge at 82% arrived batteries state of charge 91% is this about right not had AGM’s before?
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I don't consider the % display of any battery monitor as anything but an approximation/guesstimation because they can be way off without carefull massaging of parameters and calibration. I've had it show 85% when the solar controller was already well into float phase after 2h of absorption simply because after 3 weeks of heavy use the counter was all out of sync. It depends on charge efficiency and a few other settings that will all have an effect on accuracy if you don't get them right. Hardly any company is publishing those for their batteries and they change over time so...

 

What was the voltage at start of each charging event?

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It used to be the case that every motorhome had a common-or-garden ‘wet-acid’ battery for starting the engine, and that is normally still so. For UK-built models the leisure-battery was wet-acid type or - for German-built models - gel type. And the only significant thing for owners to be aware of was to ensure (if this was in fact practicable) that the appropriate wet-acid or gel charging regimen was selected on the motorhome’s on-board battery-charger.

 

Nowadays, where a gel battery was installed as original equipment, an AGM battery will usually be fitted instead, but the same basic rules apply and - to make best use of that AGM battery - the motorhome’s charging equipment should be matched to that type of battery.

 

I’ve no solar-panel experience, but - as far as I’m aware in weldted’s case - matching the battery type just means ensuring that his Burstner’s on-board battery-charger is set to charge AGM batteries. Once that’s done, whatever the combination of alternator, solar-panel and EHU does leisure-battery charging-wise is much the same as what happened when wet-acid or gel leisure-batteries were fitted - the system does its own thing and equipment modification (eg. fitting a B2B) will be required to alter this.

 

Plainly, if a motorhome’s base-vehicle has ‘smart’ electrics (eg. like the 2020 Ducato’s EcoPack)

 

https://www.fiatprofessional.com/uk/fiat-pro-world/ducato-my2020

 

this will have a potential knock-on effect on leisure-battery charging - but (hopefully) the motorhome converter will take this into account.

 

The late-Allan Evans’s website has a section on AGM batteries that should be of interest

 

http://www.aandncaravanservices.co.uk/agm-batteries.php

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Many thanks for the info Derek, we bought our van brand new Sept 2019. It was fitted with one 95 amp AGM, as we use Aires etc I added a second identical battery before leaving for France. This van is fitted with a 150 amp Alternator, 1, 100 watt solar panel. We manage three days off hook up parked up with a fair bit of tv and charging 2, phones and an IPad Pro which is used quite a bit. So quite happy with how long the batteries last but disappointed in how long they take to recover. Tried yesterday on a journey of 180 miles leaving the fridge on gas (crash regulator fitted) as this can take up to 17 amps, drove during daylight with bright but not particularly sunny weather on arrival battery at 94%% having started at 73%. Voltage at leisure batteries at start 14.6.

Voltage just before turning off 14.3. Checked with engine running on tick over . Having 2 100 amp Lithium and 2, 170 watt solar panels with an inverter/charger fitted when we return to the UK that should take care of our needs.

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For what it's worth, the legislation that relates to 'safety' gas regulators like Truma's CS and Secumotion products applies to legally using gas HEATING in a moving vehicle throughout Europe, not using other gas-fuelled equipments (hobs, ovens, fridges). This is made reasonably plain in Truma's advertising

 

https://www.truma.com/int/en/products/truma-caravan-rv-gas-fittings/truma-monocontrol-cs.html

 

https://www.truma.com/int/en/faq/operate-truma-appliances-while-driving

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Derek Uzzell - 2020-08-30 11:02 AM

 

For what it's worth, the legislation that relates to 'safety' gas regulators like Truma's CS and Secumotion products applies to legally using gas HEATING in a moving vehicle throughout Europe, not using other gas-fuelled equipments (hobs, ovens, fridges).

 

 

I don't think this is true, Derek. The terms used in the EC directives have been interpreted such that "heating" can apply to other things than "space heating", (e.g. the gas heating for an absorption fridge) and as long as all the other technical provisions of the directive are met, then these may be used on the move.

 

Extracted from the user instructions for my Dometic fridge:

 

In Europe, gas operation is permitted while

travelling only on the condition that the gas

system of the vehicle is equipped with a

hose rupture protection. The national regulations

of the respective country must be

observed.

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weldted - 2020-08-30 11:02 AM

drove during daylight with bright but not particularly sunny weather on arrival battery at 94%% having started at 73%. Voltage at leisure batteries at start 14.6.

Voltage just before turning off 14.3. Checked with engine running on tick over . Having 2 100 amp Lithium and 2, 170 watt solar panels with an inverter/charger fitted when we return to the UK that should take care of our needs.

 

From this I'm guessing the solar controller was in absorption (or near) when you started driving and at some point during the drive it went into float mode while the B2B was (still) in it's absorption phase. This assumes the B2B has a lower absorption voltage preset, possibly because it's not set to AGM? Knowing what models each of them are would make it clearer.

 

In any case, the % display is not quite true but not massively off either.

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spirou - 2020-08-30 7:25 PM

 

2019 will surely have a euro6 engine thus smart alternator and a need for a B2B

 

Ducato Euro6B engines don't have a smart alternator as standard. If I recall correctly from his earlier threads, Weldted's base vehicle was built early to mid 2018 so would be Euro 6B.

 

Edit: this post refers: https://forums.outandaboutlive.co.uk/forums/Motorhomes/Motorhome-Matters/Understanding-a-German-certificate-of-Conformity/53249/

 

 

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The accuracy of the information on a vehicle’s V5C registration document (‘log book’) wholly depends on what data were entered into the DVLA’s database when the vehicle was UK-registered. For a new motorhome bought through a UK dealership, I assume those data are input by someone at the dealership and - if the DVLA’s software has no error-checking for a particular data field - there’s obvious potential for human error at the dealership end to impact on the V5C’s details.

 

The 1st attached file below is taken from an AutoExpress article and lists Euro standards for diesel vans.

 

As the link below will show, Fiat Ducatos have been built with Euro 6 diesel motors since 2016

 

https://www.fiatcamper.com/en/news/euro6

 

Those powerplants were to Euro 6b standard and it will be noted that AdBlue was not required.

 

The next significant Ducato Euro-standard iteration appears to have been to Euro 6d-TEMP as referred to here

 

https://www.fiatcamper.com/en/news/latest-2019

 

https://www.fiatcamper.com/en/product/engines

 

and such vehicles do require AdBlue.

 

There is no Euro 6Y standard, but (for a recent-ish Ducato-based motorhome) it SHOULD be a simple matter to distinguish between a Ducato that has an AdBlue tank and one that does not. If a Ducato has an AdBlue tank there will be another REMOVABLE filler-cap below the normal diesel-fuel filler-cap as shown in the 2nd image below. No 2nd REMOVABLE filler-cap = no AdBlue tank = not to Euro 6d-TEMP standard.

 

The specification of 2020-model Ducatos is described here

 

https://www.fiatprofessional.com/uk/fiat-pro-world/ducato-my2020

 

If the EcoPack becomes standardised across all Ducatos, including specialised variants intended to be converted into motorhomes, leisure-battery charging would need to be addressed carefully. This MIGHT be OK where large-volume ‘mainstream’ converters are involved, but it would be something to beware of perhaps when a Ducato conversion is to be carried out by a low-output company.

193232111_Eurostandards.png.a50f5998d36df1cc1d1d9d206ad79fb7.png

Adblue.jpg.0bf2c2adc20c4bf4694f9516b63a9972.jpg

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weldted - 2020-08-30 10:52 PM

 

According to my log book it’s a 6Y

 

My Fiat CoC (for a Euro 6b version) shows "Euro 6 Y" (in common with many other contemporaneous Ducatos).

 

If that is shown on your V5C (though I wonder where) it will have been carried through from the CoC.

 

It is a valid designation; I can find it in lists of interchange codes for vehicle homologation, and in the German list of emissions classes mapped to "Umwelt Plakette" category.

 

It doesn't, however, run in the same series as, or denote the same characteristics as the Euro 6b/6c/6d(temp) etc. series, but seems to reference (the Y - there are other, similar suffixes) another characteristic of the particular engine or emissions test.

 

Yours, like mine, is likely to be Euro 6b in emissions terms.

 

Edited to add:

 

Confirmed by German Wiki:

 

EURO 6b - in the RDE without limit, measured according to the NEDC , first registrations from September 1, 2015 (except special permits)

 

36W0 EURO6; W; PI / CI; M, N1 I - first registrations until August 31, 2018

36X0 EURO6; X; PI / CI; N1 II - first registrations until August 31, 2019

36Y0 EURO6; Y; PI / CI; N1 III, N2 First registrations until August 31, 2019

Schadstoffgruppen nach Schl��sselnummern N_M_03.66158.pdf

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The statement re running the fridge on gas is not our normal method, it was just to see how the charging reacted to doing this. Although the fitting of a crash regulator will offer some protection in the event of a crash, but would not turn the gas off in situations such as refuelling whereAs the auto setting would. I am not endorsing running full time on gas but it was nearly an experiment.

 

Re the 6Y our van is not equipped with an Ad Blue tank.

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The general behaviour of lead-acid batteries regarding the speed of charge is that is it fast when the battery is well discharged, like 50% or so and then it slows down gradually while the battery gets charged. Once you're above 85%, charging gets slow.. Around 90%, very slow. Getting those last 10% in can take hours.
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  • 4 weeks later...

The rate of charging when on mains has now got very very slow, even when parked up on our drive with the 12 panel turned off it takes over 24 hrs to get from 82% to 93% . As I have a spare Victron Blue energy smart ip22 30 amp charger from my last van, I thought I would fit it as I am not too worried about the possible long term effect on the batteries as I will be having a complete revamp of the electric on our return to the UK with Lithium. I cant work out how to turn the Electro block charger off (EBL 630B)

So have tried running them both out the same time. According to my phone the Victron is charging at 14.4 volts 9.7 amps but the vans display shows the same voltage but a discharge of 9 amps and the percentage of charge is decreasing. The Victron is connected directly to the batteries + of batt 1 - of battery 2 must be upsetting something but what? Have ran two chargers at once in my last van with no problems as each responds to the demands required.

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What is the display you're using that tells you SOC? A shunt should be the only thing directly connected to the - pole of the battery so very close to it. Everything else connects via shunt so it can measure everything going in/out. Looks like this https://www.wattuneed.com/en/victron-energy/2110-victron-shunt-500a1000a2000a-50mv-0712971132436.html

 

Suppose it could also be internal within the distribution/charging unit in which case things get more complicated for wiring extra stuff.

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Don't let anyone tell you otherwise, an AGM battery requires 14.7Vdc to full charge it. At 14.3Vdc an AGM battery will only charge to 50%, which equates to 12.5Vdc terminal voltage. Yes, believe it...!!!

 

Motorhome manufacturers have been getting this wrong for many years, and completely denying any responsibility. if your base vehicle has got an AGM battery as starter, the it will almost certainly have a 'smart' alternator, well capable of maintaining the starter battery state of charge but converters have ignored this requirement for the habitation batteries and blithely fitting AGM batteries because the are 'vogue' at the moment and not providing a charger with 14.7V capability.

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Set the Victron to 14.7 disconnected the negative from leisure batteries to van left Victron on for 24 hrs. Also noticed the 50 amp fuse from L/B to habitation was quite warm, removed it with little resistance cleaned with electric contact spray, twisted the blades slightly. Now everything put back to original spec disconnected second charger. Now if I run the hab batteries down to around SOC 90% plug into hook up display panel shows 14.7 volts 9 amps which falls steadily after six hours shows 14.7 volts 0.7 to 0.8 amps charge. Next morning 13.8 volts no amps Charge batteries at 100%. Wonder if high resistance or just poor conductivity was the cause. Only time will tell. Roll on my Lithium conversion. Many thank to all.
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  • 3 weeks later...
Derek Uzzell - 2020-08-31 7:15 PM

 

 

If the EcoPack becomes standardised across all Ducatos, including specialised variants intended to be converted into motorhomes, leisure-battery charging would need to be addressed carefully. This MIGHT be OK where large-volume ‘mainstream’ converters are involved, but it would be something to beware of perhaps when a Ducato conversion is to be carried out by a low-output company.

 

I just read a post on an Adria forum that DC/DC chargers are mandatory on certain Ducato builds "DC/DC converter MANDATORY FOR 140BHP AUTO, 160BHP & 180BHP" I guess this means a smart alternator is now installed but I wonder if it is one that uses higher voltages during braking as I understand not all smart alternators do this? the new owner also confirmed that the van has the Start/stop feature so perhaps it does use 'regen braking"

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As you say, the latest Adria data (600 SPB model information here)

 

https://www.adria.co.uk/technical-data/2995

 

states that - if the optional 140BHP AUTO, 160BHP & 180BHP motors are chosen - a DC/DC converter is mandatory.

 

The Fiat Professional blurb for 2020 model-year Ducatos

 

https://www.fiatprofessional.com/uk/fiat-pro-world/ducato-my2020

 

said

 

With updated Euro 6D-Temp engines Ducato provides even more efficiency, performance and eco-friendly credentials. The EcoPack will come as standard later in the year, providing the very best in smart technology applied to safeguarding the environment. The EcoPack includes the Start & Stop system, the smart alternator; the electronically-controlled fuel pump, which gives energy savings and greater combustion efficiency and the ECO switch that supports the driver in saving fuel: all to the benefit of the total cost of ownership.

 

and this review may be of interest

 

https://www.parkers.co.uk/vans-pickups/fiat/ducato/2011-review/

 

Although the new ‘all electric’ Fiat e-Ducato does have regenerative braking (which is what one would probably expect)

 

https://www.automotiveworld.com/news-releases/fiat-professional-confirms-pricing-and-specification-of-fiat-e-ducato-for-uk-market/

 

I can’t find anything to suggest that the latest diesel-fuelled Ducatos might have it (If it had, Fiat would have been only to keen to advertise this!) I don’t know what the Ducato smart alternator does during braking.

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