Help! Is my EHU actually charging my batteries?

[trevskoda]

Thanks all. Plenty of bed time reading here and plenty to chew on.
Bottom line .... I wish I'd bought a lead carbon but was put off by tales of not getting it fully charged. I actually thought I was playing it safe with my purchase. It seems not. Maybe it would be cheaper in the long run to write off my new purchase and start again?

Sell them on.

 

[merl]

Meri, can you recommend a non smart charger. Everything I look at seems to be "smart"

IMmm, dont really like recommending anything that I havent had decent experience of. TBH I'd have suggested using a Ctek like Kev but only last week someone here had their batteries boiled by one so I'm a little reluctant now! There's this one on ebay

Nordelettronica 12v 17amp Battery Charger BE 287 12v campervan motorhome caravan | eBay

Find many great new & used options and get the best deals for Nordelettronica 12v 17amp Battery Charger BE 287 12v campervan motorhome caravan at the best online prices at eBay! Free delivery for many products.

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Similar to what I use now. The old 'nord' chargers used overheat when running flat out for a period of time and also had an internal transformer issue. (I know, I've had to repair mine twice and fit a fan!) I'm not sure if they've fixed the transformer issue but possibly have because I've not heard of any issues in the last few years, the overheating has been addressed by them fitting a fan to the newer models which the above is. Deffo doesn't have 'pulse'.
I also bought one of these recently

12V 30A Leisure LCD Battery Charger For Caravan Campervan Motorhome Marine Boat 701160636404 | eBay

Find many great new & used options and get the best deals for 12V 30A Leisure LCD Battery Charger For Caravan Campervan Motorhome Marine Boat at the best online prices at eBay! Free delivery for many products.

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Now, it's advertised as a 30A charger but actually only delivers 20A but for the dough it seems pretty decent. It's nicely constructed to be honest and I don't think it's 'pulse' either but I'll check it out with my scope tomorrow and let you know.
I'm sure others will chip in with suggestions for reliable pulse chargers

 

[Pudsey Bear]

As soon as I see "Nordelettronica" I walk away, I've had three vans with their gear in and all had issues, this van has a control panel from them, and it was acting up so I got a new one (£140), I've had three replacements since then and it still won't let me turn on the bathroom light or adjust the onboard clock.

 

[Okta]

Ok, you asked for.it! Snuggle down it'll soon be sleepy time. What's below is simplified but hope it helps.

Thanks for the explanation, very helpful. The reason I suggested keeping the charging sources separate is my own experience with my Efoy fuel cell. The Efoy interrupts its charging periodically so that it can test the rising voltage of the battery without its own influence. I thought perhaps some smart chargers might operate similarly and only start their bulk phase if they sensed a low voltage and might get confused by the solar voltage.

 

[wildebus]

As soon as I see "Nordelettronica" I walk away, I've had three vans with their gear in and all had issues, this van has a control panel from them, and it was acting up so I got a new one (£140), I've had three replacements since then and it still won't let me turn on the bathroom light or adjust the onboard clock.

If I had a van with that kit, I would remove it on the first failure and fit anything in its place.

 

[Pudsey Bear]

If it had been a charger etc it'd be straightforward I suppose but the control panel is wired into everything it even controls the lights which do not have their own switches, and it monitors water and battery levels too (which agree closely with my meter and the plugin displays I bought ) and I would need your type of skills to find and fit an alternative.

 

[merl]

As soon as I see "Nordelettronica" I walk away, I've had three vans with their gear in and all had issues, this van has a control panel from them, and it was acting up so I got a new one (£140), I've had three replacements since then and it still won't let me turn on the bathroom light or adjust the onboard clock.

All of the decent modern equipment is built to a similar standard and somewhere far afield. I have a charger that's somewhat old school, and just 2 stage. (all you really need IMHO) Works brilliantly and the circuitry is dead simple and bullet proof. Problem is it has a massive mains transformer, and is dead inefficient and gives off quite a bit of heat, weights a ton and is only 10A. Peeps want a modern charger to supply 15-20A or more, be power efficient, lightweight and small and all of those requirements are a disadvantage WRT reliability especially when folks want it cheap too!
I tend to lean toward mid to low budget where I don't mind it failing in the future and more expensive if it's a critical part but the stuff is for my own personal use and I fortunate enough to repair many things if they break down. If I were supplying stuff to customers as my living I'd probably go higher end like Victron but even their stuff goes wrong sometimes. It's a lottery Basically Kev.

 

[merl]

If it had been a charger etc it'd be straightforward I suppose but the control panel is wired into everything it even controls the lights which do not have their own switches, and it monitors water and battery levels too (which agree closely with my meter and the plugin displays I bought ) and I would need your type of skills to find and fit an alternative.

The problem could well be in the muti core interconnects between the panel and the main unit. Try pulling and pushing the plugs on and off several times to clean the contacts at both ends and inspect them just in case there's a breakage at the plug. There are several of them but if you dont want to do them all I can dig out the schematic if you want the correct number for the one associated with the lights.

 

[Pudsey Bear]

Nah, I'll leave it alone I've had a few replacements and done the plug on/off thing to death, no change and they look very clean anyway, no verdigris or corrosion at all, my own thought and that of the supplier is that Swift buy them and then do what they like with then, and I have proof that the cable supplied with the panel is NOT the one the actually fitted as I sent them pictures as the diagram they sent to ensure correct connection didn't agree with what I was seeing.

So long as I can control the pump and other lights, and it monitors the batteries and roughly the water tanks, (it always says the waste is full) it'll do as is, I do have the manual for it, but the panel doesn't respond when trying to change the time, and there doesn't seem to be a facility to turn the bathroom lights on or off, I have messed and pressed and have got them on, then can't find how to turn them off (you won't find my picture next to methodical in the dictionary) so I took the bulbs out.

 

[merl]

Thanks for the explanation, very helpful. The reason I suggested keeping the charging sources separate is my own experience with my Efoy fuel cell. The Efoy interrupts its charging periodically so that it can test the rising voltage of the battery without its own influence. I thought perhaps some smart chargers might operate similarly and only start their bulk phase if they sensed a low voltage and might get confused by the solar voltage.

I've never come across a MH charger that's as smart as that TBF!
Some chargers have an initial 'voltage check' to make sure there's actually a battery connected before starting up cos the modern switch mode chargers can soon fail if left working into 'no load'.
I guess it makes sense to shut your power cell down under a 'no charge' situation rather than leave it running the battery charger and the charger not actually doing nowt, hence the occasional check to see what's happening?

 

[wildebus]

Quite a few chargers (the better ones) do momentarily cut their charge on a regular (and very frequent) basis so the 'real' battery voltage can be read, so the same kind of thing as the EFOY. It is a very short pause and is not generally evident when checking the output yourself with a meter but you might occaionally catch it.
Different ones do it at different times. The ones which I have actually noticed quite often with this pattern is the Victron MPPTs. I think it is probably a bit more than a simple voltage check as it is 'catchable' but they have a very short pause every 10 minutes.

 

[Okta]

I've never come across a MH charger that's as smart as that TBF!
Some chargers have an initial 'voltage check' to make sure there's actually a battery connected before starting up cos the modern switch mode chargers can soon fail if left working into 'no load'.
I guess it makes sense to shut your power cell down under a 'no charge' situation rather than leave it running the battery charger and the charger not actually doing nowt, hence the occasional check to see what's happening?

The Efoy seems to monitor the voltage periodically throughout the charge but only does a full shut down when the voltage and tail current parameters are met. These parameters are adjustable. It will then stay in sleep mode until the low voltage setting is triggered. It also wakes up if it gets close to freezing and warms itself up.

 

[david how]

I've just replaced a Banner 3 yr old lead acid that appeared to be no longer holding charge. I made a conservative choice and stuck with lead acid via Alpha batteries and got a 110 AH expedition plus, semi traction.
Now after a day charging this new leisure bat via EHU and a day charging Vehicle battery, it seems like no extra charge has been delivered to either.
eg the new leisure battery shows full charge on the Sargent control panel, but drops back one notch as soon as I switch interior lights on. That's exactly a symptom I had with the battery I've just taken out. In the past when all was working well, the fully charged lights on the control panel rarely dropped at all.
I've checked all fuses on the Sargent EC155 and all seems in order.
How can I check if the charger is actually providing charge to the batteries?
(I've a solar panel which appears to be charging a bit in the dim Scottish daylight, but does this confuse any diagnosis?)
Any thoughts please?

I think you should check the earth cable. I haven't read all the replies so it might have been mentioned already. It sounds like a classic case of bad earth. That contact needs to be really good or it could arc and reduce current flow.

 

[mistericeman]

Oh no. I was following it quite well. Now I'm lost. My brain doesn't seem to be wired to grasp electrics. Amps!? What do I do now?

Think of the battery as a bucket
And the charger as a tap filling the bucket ....

Small amount of amps is the tap at a trickle


Lot of amps is the tap wide open

 

[Okta]

Think of the battery as a bucket
And the charger as a tap filling the bucket ....

Small amount of amps is the tap at a trickle


Lot of amps is the tap wide open

and not enough volts is lack of water pressure so you only get a trickle even with the tap wide open.

 

[myvanwy]

Great analogy.

 

[trevskoda]

Great analogy.

anal ogy,

 

[wildebus]

Pudsey leave the charger on 24/7 as its they way it works, timmers were for the old constant chargers to stop the battery boiling dry, now go to bed, give you head a break.

if the charger is a decent one, and especially if it has a "storage" mode (this is a mode that automatically puts the charger output into a slightly lower voltage than float), then leaving it on 24/7 as Trevor suggests is fine and can often be the best for the battery.
Turning the charger off and back on makes it go through all the charging modes from the start whether the battery needs it or not - because the charger doesn't know if the battery needs it or not. It may only stay at those initial bulk and absorption modes for just a short time but it still does it.

Does it use power when left on? it depends on the charger really. there must be some power used as smart chargers contain electronics that are always running when powered, but you could be talking milliamps.
I know my setup is different and 'fancier' than yours, but this screenshot may be of interest. I've had my EHU lead in for the last week in I suppose. The batteries are fully charged so the requirement now is really just providing power to whatever is needing it.

Because the solar can provide all the electrical demands at this point, the mains charger, although plugged in and in float mode, is not drawing any power from the mains/'shore' supply (in this case even the electronics within it will be supplied from Solar in fact). There would be no point in unplugging the EHU. But .... if I did and I plugged it back in, the charger would go into the Bulk-Absorption-Float cycle, as that is what it is programmed to to when powered up, and I would end up drawing power that is not neccessary. Unplugging ends up being less efficient!

(the negative current on the "60A B2B + AMT" is the trickle pulse to the Starter Battery. Solar is maintaining the Starter as well of course).

 

[trevskoda]

A charger is not required by me from end of jan as the solar is working well on all the batteries, hab and starter.

 

[Pudsey Bear]

I went and put it on 24/7 yesterday afternoon, I have plug in meter to check power usage so I'm leaving that few days to see what it uses.