Help! Is my EHU actually charging my batteries?

[RSD7a]

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

Meri, the charger you bought the other day ... How long would you leave that attached to boost your leisure battery. Would it need time limiting? Thanks

 

[RSD7a]

Put a multimeter across the battery!
A fully charged battery at rest is around 12.8v. Plug in the mains, and check the voltage again. It should jump to 13.8v to 14.5v depending on the battery’s state of charge.

Thanks Tony. See my post #6. How do you read those figures? (Readings taken in the dark to cut out the solar panel)

 

[trevskoda]

I don't have that kind of money Trev, I already have a controller that does the same, if I bought a Votronic I'd have two, then someone else would come along and suggest some other method, in fact, they have but I have to work with what I have.

What irks me most is not being able to get to grips with testing or fitting things myself, and conflicting advice and suggestions is most confusing, and often not as helpful as intended as I'm not a sparky or understand most of it.

If the control unit is the same then both sets of batteries should be hitting 14.4 before dropping back to a float of around 13.4 to 13.6 v.
Dont panic life is to short.

 

[Pudsey Bear]

My name's not Pike...

 

[merl]

Meri, the charger you bought the other day ... How long would you leave that attached to boost your leisure battery. Would it need time limiting? Thanks

With either of the chargers I mentioned you'd use them to REPLACE your current Sargent charger.
Ideally you'd disconnect the mains supply to the sargent and also isolate the connection to the battery too just to stop any current drain from the battery to the electronics in the charger. I'm not 100% sure because I dont have access to the wiring diagram but you'd probably be able to do this by simply removing 2 fuses on the input and output serving the charger. However you do it bear in mind you may need to re-connect it in future if the new charger fails so you'll have a back up.
The new charger obviously needs a mains power supply and a connection to the battery, simplest way would be plug into a 13a socket but you may not have one in a suitable place so you'll have to figure that out. I think both chargers have an IEC connector, so if the sargent has a IEC mains lead you'd simply move that over to the new charger!
Output from the charger straight to the battery, best if you dispense with the clips and make a proper connection with ring connectors.
3A fuse on the mains input (depends on how you end up connecting it) and a 25A fuse on the output . I think both have an inbuilt output fuses but if not you'll have to add an inline fuse. Personally I would avoid a blade fuse at this sort of current and go for MIDI or ANL.
Consider it's ventilation when positioning.

 

[RSD7a]

With either of the chargers I mentioned you'd use them to REPLACE your current Sargent charger.
Ideally you'd disconnect the mains supply to the sargent and also isolate the connection to the battery too just to stop any current drain from the battery to the electronics in the charger. I'm not 100% sure because I dont have access to the wiring diagram but you'd probably be able to do this by simply removing 2 fuses on the input and output serving the charger. However you do it bear in mind you may need to re-connect it in future if the new charger fails so you'll have a back up.
The new charger obviously needs a mains power supply and a connection to the battery, simplest way would be plug into a 13a socket but you may not have one in a suitable place so you'll have to figure that out. I think both chargers have an IEC connector, so if the sargent has a IEC mains lead you'd simply move that over to the new charger!
Output from the charger straight to the battery, best if you dispense with the clips and make a proper connection with ring connectors.
3A fuse on the mains input (depends on how you end up connecting it) and a 25A fuse on the output . I think both have an inbuilt output fuses but if not you'll have to add an inline fuse. Personally I would avoid a blade fuse at this sort of current and go for MIDI or ANL.
Consider it's ventilation when positioning.

Thanks Merl. I'd misunderstood your recommended use of the charger. Hadn't realised you meant it as a replacement. I was thinking of it as a top up. Would that make any sense?

But going with your post above, if I disconnect the Sargent from the mains and substitute the new charger how will the Sargent's distribution function (if that's the correct term) work, ie sending power to the fridge, various lights, water pump etc?

 

[Pudsey Bear]

I think any charger needs to be stand-alone, my solar controller is supposed to charge the VB but isn't so I'm using the Ctek, if the solar improves and starts charging the VB, then the Ctek will see that as a higher volts value and go into standby so pointless having it connected, I had this issue on my self build so I just unplugged the EHU and let the solar do it's job until I needed to put the fridge onto 230v for a trip.

 

[AllanD]

Thanks Meri. I'd misunderstood your recommended use of the charger. Hadn't realised you meant it as a replacement. I was thinking of it as a top up. Would that make any sense?

But going with your post above, if I disconnect the Sergant from the mains and substitute the new charger how will the Sergant's distribution function (if that's the correct term) work, ie sending power to the fridge, various lights, water pump etc?

I know you’ve directed the question to merl but just a thought. The later Sargent charger (PX300 I think) will output the 14.4 volts required for absorption (then when less than 2 volts is being taken by the battery it drops to 13.6) so maybe that would be a good choice if Sargent advise that it will integrate seamlessly?

 

[Pudsey Bear]

I just went down to drain the water in the van and took a couple of pictures.

After 2 days 6 hours n 2 minutes less than half a kilowatt so far since Monday 11am

Obviously not SOC but showing that the Ctek is putting some in.

 

[merl]

Thanks Merl. I'd misunderstood your recommended use of the charger. Hadn't realised you meant it as a replacement. I was thinking of it as a top up. Would that make any sense?

But going with your post above, if I disconnect the Sargent from the mains and substitute the new charger how will the Sargent's distribution function (if that's the correct term) work, ie sending power to the fridge, various lights, water pump etc?

You can use a small charger alongside the Sargent or you could use a larger charger (15A ish or over) alongside OR as a replacement.
The battery connections to the EC155 will remain so distribution o12V to wherever is still possible.
The output from the charger is easy to disable, you just pull fuse No12.
Now, the info that's available on the EC155 is limited but since posting my previous message I've checked and removing the power from the EC155 will also remove power to all your 240V sockets so unfortunately we cant do that to remove power to the Sargent charger, simply switching it if off at the main rocker switch may work (cant tell from the circuitry diagrams) but if not there may be a bit of fiddling to do internally with the EC155 to disable the inbuilt charger which should be dead simple. If the main switch doesn't work and you dont want to open the unit up then leave fuse 12 in place and leave both chargers running.

 

[wildebus]

Ref the EC155, it is quite simple to be honest:

If there is no AC into in, then there is no AC out to any circuits - the EC155 is the AC Consumer Unit as well as the DC Distribution Unit and DC Chargers.
If you don't want to use the built-in AC Battery Charger, you just leave the big red switch off
If you don't want to use the built-in Spilt-Relay, the easiest way is just remove the D+ input to the EC155

I would recommend NOT pulling any fuses or messing with any wiring in an attempt to disable the Charger for two reasons:
1) there is no need - you just use the switch to turn it off
2) You may have a reason to use the charger in the future. Either if the replacement charger goes wrong, or you want to charge the starter battery with the EC155.

 

[merl]

Always intended to make the sargent charger easily re-useable. I guessed the main switch would simply power the charger but without an internal schematic or your individual experience I couldn't be sure, thanks for confirming
I was concerned about the charger's internal electronics needlessly drawing some current from the battery hence pulling fuse 12. Again couldn't be sure of the chargers electronics without a schematic so again thanks for confirming. Cheers David.

 

[wildebus]

FWIW, I quite like the Sargent units for their 12V Power Distribution and the AC Consumer Unit section is of decent quality, but the Charging side is usually woefully poor both in the way the chargers work and their current output.
I'd always go with fitting an external charger (both AC and B2B ideally) and bypassing those aspects of the Sargent.
Having the ability to switch the internal charger to the Starter Battery is a handy thing to be able to do if that battery needs a bit of a boost.
I don't use any of the charging features of the Sargent EC325 unit I have and I believe the unit should last longer for that as a bonus as there is a lot less heat build up in the enclosed box due to that.

The latest Sargents are better in the charger designs, but the outputs are still low, especially considering the type and size of batteries that a lot of people are now fitting.

Oh, something that can cause confusion .... the following is true of the Sargent EC325 and EC328 and likely others with an LCD information panel .... If the Charger is switched off, the control panel will say the Mains Supply is off. This is not the case at all and what is really means is the Charger is off. But it is easy to take that information at face value and assume the charger switch off is also disconnecting all the AC circuits.

 

[merl]

Meri, the charger you bought the other day ... How long would you leave that attached to boost your leisure battery. Would it need time limiting? Thanks

The additional charger will automatically fully charge the battery and then the output will drop to the float voltage so it could be left on permanently however there will be running costs. Turning the charger off and re topping up occasionally is an option, time between charges will depend on what you've got in the van consuming standby current. I assume you dont have solar?

 

[merl]

FWIW, I quite like the Sargent units for their 12V Power Distribution and the AC Consumer Unit section is of decent quality, but the Charging side is usually woefully poor both in the way the chargers work and their current output.
I'd always go with fitting an external charger (both AC and B2B ideally) and bypassing those aspects of the Sargent.
Having the ability to switch the internal charger to the Starter Battery is a handy thing to be able to do if that battery needs a bit of a boost.
I don't use any of the charging features of the Sargent EC325 unit I have and I believe the unit should last longer for that as a bonus as there is a lot less heat build up in the enclosed box due to that.

The latest Sargents are better in the charger designs, but the outputs are still low, especially considering the type and size of batteries that a lot of people are now fitting.

Oh, something that can cause confusion .... the following is true of the Sargent EC325 and EC328 and likely others with an LCD information panel .... If the Charger is switched off, the control panel will say the Mains Supply is off. This is not the case at all and what is really means is the Charger is off. But it is easy to take that information at face value and assume the charger switch off is also disconnecting all the AC circuits.

Thanks.
When you say the outputs are still low is that current or voltage? or both!
I guess there's the typical extra 3rd logic cable coming from the charger output that gives the 'power on' signal to the board and then to the control panel?

 

[wildebus]

Thanks.
When you say the outputs are still low is that current or voltage? or both!
I guess there's the typical extra 3rd logic cable coming from the charger output that gives the 'power on' signal to the board and then to the control panel?

Both.
My EC325 (Fitted as standard to a fairly high end Autotrail) is a fixed 13.8V output (poor) and meant to be 25A but measured at more like 10A. (Meant to be a 300W PSU).
The controller is an intelligent one and I suppose it has a signal to tell it the charger is off. It is connected to the PDU via a low voltage date/ribbon cable. Not something I have bothered investigating as no reason to.

 

[RSD7a]

Merl & Widebus, thanks for sticking with my questions and for the treasure-trove of info so freely provided. Again, much to digest here. Happily, FWIW, I can confirm that my 13a sockets remain live with Sargent switched off and it's a relief to know it's distribution function will remain active.
I suspect I will have additional questions but for now, there's enough to keep me going

 

[RSD7a]

The additional charger will automatically fully charge the battery and then the output will drop to the float voltage so it could be left on permanently however there will be running costs. Turning the charger off and re topping up occasionally is an option, time between charges will depend on what you've got in the van consuming standby current. I assume you dont have solar?

I do have solar actually Merl, which with old Banner lead acid largely kept me going outside of the winter months.

 

[merl]

Both.
My EC325 (Fitted as standard to a fairly high end Autotrail) is a fixed 13.8V output (poor) and meant to be 25A but measured at more like 10A. (Meant to be a 300W PSU).
The controller is an intelligent one and I suppose it has a signal to tell it the charger is off. It is connected to the PDU via a low voltage date/ribbon cable. Not something I have bothered investigating as no reason to.

Only10A from a 25A charger Overstating current capacity seems to be standard practice with all the standalone chargers (Chinese) on ebay/amazon etc, they know that peeps with a DC clamp meter will be few and far between but I wouldn't have expected it from Sargent, very naughty.
In an earlier MH of ours I fitted some cheapo led replacements to the lights, the sort with multiple SMD leds, everything was fine when off grid but when we were on a site with EHU, the charger was on it's bulk phase and so eventually the system was up to around 14.7V and at this point the LEDs got so hot they unsoldered themselves from the board and fell off!
Maybe it's the fear of overvoltage that makes Sargent feel they have to use what's basically a power supply rather than a full blown charger? Who knows as it's not a choice other manf make and other than my LED experience I've never come across 14.4V+ affecting equipment, have you?

 

[Nabsim]

I have multiple charge sources, 2 x solar, B2B and mains charger. Sometimes I can have all three sources charging at the same time (although that’s rare, would usually be solar and mains) and no problems although I have Lifepo4 battery’s. If I have mains charging it means token or no charge on solar though unless sun briefly breaks through