Help! Is my EHU actually charging my batteries?

RSD7a

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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'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?
Put a meter on the battery, turn on the charger and see if the voltage increases (it should go up to 13.8V eventually with the EC155).

If you don't have a meter to check this, then it would be a good idea to get one for trouble-shooting.
 
It's at 14.5 without the charger on. But the moment I draw power (ie switch on habitation lights)the battery condition light on the control panel loses one green light. That was a symptom I had with the "duff" battery. But only as it began to fail.
Maybe I need to disconnect the solar panel to get the reading I need?
 
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At night (so the solar isn't involved) turn the charger off; wait 30 minutes and check the battery voltage with a meter.
Do not alter the use of any 12v device
Switch the charger on and check the voltage again.

If the voltage goes up then the charger is doing its job.
 
At night (so the solar isn't involved) turn the charger off; wait 30 minutes and check the battery voltage with a meter.
Do not alter the use of any 12v device
Switch the charger on and check the voltage again.

If the voltage goes up then the charger is doing its job.
Thanks. V helpful and clear.

My readings are

12.64 with charger off
13.36 with charger on
Does that sound about right?

If so, I wonder why after many hours on EHU the new battery appears to drop off with minimal load applied. (Top green light in the Sargent control panel goes out almost immediately).
 
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Thanks. V helpful and clear.

12.64 with charger off
13.36 with charger on
Does that sound about right?

If so, I wonder why after many hours on EHU the new battery appears to drop off with minimal load applied. (Top green light in the Sargent control panel goes out almost immediately).
the voltage the sargent unit is detecting is not necessarily the voltage of the battery. They usually read low. Have you actually checked the voltage on the battery with the sargent control panel off and with it on? What is the difference?

Also bear in mind as soon as you add a load to a battery, the voltage will drop. That is normal and the voltage then goes up when the load is removed.
 
Volts are not everything you must also test for amps it is quite possible to have a charger producing good voltage but to be producing very little in the way of current it may only be producing a few mA.
 
Volts are not everything you must also test for amps it is quite possible to have a charger producing good voltage but to be producing very little in the way of current it may only be producing a few mA.
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?
 
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"the voltage the sargent unit is detecting is not necessarily the voltage of the battery. They usually read low. Have you actually checked the voltage on the battery with the sargent control panel off and with it on? What is the difference?"

My readings were from a meter on the battery. The Sargent control panel doesn't have numbers. Just lights.

Can you explain to me if there is a difference between readings with control panel off and on, what would that mean? Thanks.
 
"the voltage the sargent unit is detecting is not necessarily the voltage of the battery. They usually read low. Have you actually checked the voltage on the battery with the sargent control panel off and with it on? What is the difference?"

My readings were from a meter on the battery. The Sargent control panel doesn't have numbers. Just lights.

Can you explain to me if there is a difference between readings with control panel off and on, what would that mean? Thanks.
When the panel is on, you have turned on the 12V habitation electrics, so you will have additional load on the battery.
When the panel is off, the only hab electrics is the permenant 12V, used for things like the fridge electronics if it has any.

You didn't quote a battery reading with and without the control panel on. Is there much of a difference?
The 5 led bars on the EC50/EC51 panel are not much better than useless TBH. At the very least you want to fit a voltmeter so you can read the battery whenever you want.
 
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Thanks. V helpful and clear.

My readings are

12.64 with charger off
13.36 with charger on
Does that sound about right?

If so, I wonder why after many hours on EHU the new battery appears to drop off with minimal load applied. (Top green light in the Sargent control panel goes out almost immediately).
Here are my thoughts on the problem.

Your charge voltage of 13.36 is far too low. The battery specification says to charge at 14.4V and that 13.8V is needed to keep it topped up when charged. Alpha describe the battery as having hybrid technology and refer to glass mat separation. It sounds like a type of AGM which are generally very fussy about being charged at the correct voltage. I would talk to Alpha about the charging requirement and whether it needs treating as an AGM battery. If it is an AGM type of battery here is Alpha Batteries detailed guide.

The Sargent EC155 may not be a suitable charger for your battery. According to the Sargent description the charger has a fixed voltage of 13.8V which is no more than a top up voltage, not enough to charge the battery properly. I have slowly destroyed more than one battery using a similar fixed voltage charger. My personal opinion is that they should not be described as a charger but as a power supply. Here is a link to the Sargent document.

I've a solar panel which appears to be charging a bit in the dim Scottish daylight, but does this confuse any diagnosis?
Yes, I think it does confuse the diagnosis. A solar panel/controller can produce a good voltage but may only be delivering milli-Amps of power in low angle poor light conditions. It just confuses the voltage readings and may even be interfering with the lower voltage charging of other devices.
 
Here are my thoughts on the problem.

Your charge voltage of 13.36 is far too low. The battery specification says to charge at 14.4V and that 13.8V is needed to keep it topped up when charged. Alpha describe the battery as having hybrid technology and refer to glass mat separation. It sounds like a type of AGM which are generally very fussy about being charged at the correct voltage. I would talk to Alpha about the charging requirement and whether it needs treating as an AGM battery. If it is an AGM type of battery here is Alpha Batteries detailed guide.

The Sargent EC155 may not be a suitable charger for your battery. According to the Sargent description the charger has a fixed voltage of 13.8V which is no more than a top up voltage, not enough to charge the battery properly. I have slowly destroyed more than one battery using a similar fixed voltage charger. My personal opinion is that they should not be described as a charger but as a power supply. Here is a link to the Sargent document.


Yes, I think it does confuse the diagnosis. A solar panel/controller can produce a good voltage but may only be delivering milli-Amps of power in low angle poor light conditions. It just confuses the voltage readings and may even be interfering with the lower voltage charging of other devices.
Thanks. V useful suggestions though the thought of upgrading the Sargent unit is a bit daunting. Who could do it up here in East Lothian I wonder.

Meantime, I have access via a neighbour to a free standing smart charger. Is it worth giving the new battery a blast with that to get it fully charged. And would that get me to a point where the Sargent "charger" would do its job?

I'll speak to Alpha and Sargent next week.
 
I have a couple similar to this, cheap and cheerful, mine also displays the temp and the amps the USB device plugged in is drawing, I have one on the dash and another in the hab, not 100% accurate But on checking with my meter it was very close so I trust them, and it saves having to mess about with a meter the info is there at a glance.

I also bought a Ctek 5amp smart charger to keep it all going as the usual onboard chargers are rubbish as has been said above.




Cheaper
 
From the reading you have supplied it indicates that the Sargent is connected and operating correctly however:-
A charger should have a charge voltage of around 14.6V-14.8V depending on battery chemistry (AGM is typically slightly higher than standard or Gel). When the charger detects the battery is full the voltage drops to around the 13.8v mark. Having the 14.6-8 charge voltage is vitally important to a batteries health and effectively the Sargeant never gives your battery it's crucial full charge so as Okta said, It appears the Sargent isn't suitable as a battery charger, with it's only 13.8V output your going to ruin your battery quickly.
Your solar should be set at the higher voltage but at this time of the year it's going to struggle getting the battery FULL.
I'd get the Sargent swapped out ASAP and in the meantime use your neighbours charger as you suggested overnight and then disconnect one of the battery leads until you get the new charger in. If you must leave the battery connected because you have a tracker/alarm then leave the sargent on full time after the battery has been charged overnight.
Don't concern yourself about the amps/volts from your solar right now, it's a red herring and not actually accurate info.
 
Thanks. V useful suggestions though the thought of upgrading the Sargent unit is a bit daunting. Who could do it up here in East Lothian I wonder.

Meantime, I have access via a neighbour to a free standing smart charger. Is it worth giving the new battery a blast with that to get it fully charged. And would that get me to a point where the Sargent "charger" would do its job?

I'll speak to Alpha and Sargent next week.
Some years ago I had a similar problem. I didn’t replace the 12V distribution unit, I just disconnected it from the mains and installed a separate smart charger with the correct charging profile for my battery.

Yes give your battery a good long charge with your neighbours smart charger. I would disconnect the battery altogether from everything. A smart charger can be confused by other charging sources. For example if your solar is putting out 14.4V but with no Amps to do any work the smart charger may detect the 14.4V and think the battery is full and shut back wrongly thinking it’s job is done.
 
Some years ago I had a similar problem. I didn’t replace the 12V distribution unit, I just disconnected it from the mains and installed a separate smart charger with the correct charging profile for my battery.

Yes give your battery a good long charge with your neighbours smart charger. I would disconnect the battery altogether from everything. A smart charger can be confused by other charging sources. For example if your solar is putting out 14.4V but with no Amps to do any work the smart charger may detect the 14.4V and think the battery is full and shut back wrongly thinking it’s job is done.
After posting above I thought of the additional charger option which would work as long as the battery gets a decent long period of time on the charger without any significant loads at the same time. No need to keep disconnecting and re-connecting the additional charger just leave it connected.
As I said the voltage/current comment from the solar is a non issue and incorrect. If you'd like me to elaborate I will but for now ignore the comment.:)
 
I wouldn't have an additional charger on at the same time, I turn the van charger off as it is just a waste of time and use the Ctek on it's own, I also think it could confuse the Ctek if it took the van charger input into it's calculations.
 

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