Mains hookup at home

[Ralph]

My mains unit has failed twice in 2 years and I'm waiting for another replacement. In conversation with the dealer (Hayes) I was told that I shouldn't keep the van plugged into the mains when at home as is my habit. I do it to keep the batteries charged and to provide mains for vaccuming etc. when required. I have always done this with all my vans and not had a problem.

Anybody have any thoughts on this?

 

Also they tell me that Pilote have recommended fitting a surge protector at quite high cost! Surely if this is required they should supply it, not me, or am I missing something?

 

 

[naittaw]

I keep the mains hooked-up, especially over the winter to provide a bit of background heat. I turn off the leisure battery charger to prevent the battery drying out. Never had any problem.

[Thai Bry]

Ralph

I've always hooked up to the mains when at home, but only for a couple of days just prior to us setting off on any journey.

Thai

[Clive]

Before I had a solar panel I connected the mains hookup one day per fortnight only. Now it only gets connected to run the hoover as the solar panel keeps both batteries topped up.

 

 

Do you have sufficient ventilation for your mains charger unit?

 

If two have failed in 2 years it sounds like its inadequately protected and I too would challenge your supplier regarding its durability.

 

 

 

[John Keats]

Some technical knowledge is needed here I believe on the use and safety of batteries when not in regular use.

 

Is it better to allow batteries to loose charge to around half before re-charging ........... or keep them fully charged all time.

 

Does this depend on battery age?

 

What is the allowable time span from the manufacturers first full charge to being sold in a shop ( 3 years ? )

 

Does the battery have a limited life regardless of use, or not ?

[Thai Bry]

John Keats - 2007-07-19 11:26 AM Some technical knowledge is needed here I believe on the use and safety of batteries when not in regular use. Is it better to allow batteries to loose charge to around half before re-charging ........... or keep them fully charged all time. Does this depend on battery age? What is the allowable time span from the manufacturers first full charge to being sold in a shop ( 3 years ? ) Does the battery have a limited life regardless of use, or not ?

Hi John

I've been told that you do not tend to have as much trouble with Gel batteries, as they are lower maintenance than the traditional liesure ones. So we specified a couple of 110ah gel ones on our new van.I hope I've done right, I'm sure someone will be along to say otherwise if I've not.

As for the charging bit, I know it use to be the case on older laptops, where it was advisable to totally let the battery drain to zero, before re-charging, something to do with memory batteries. But this is not the case nowadys, or so I'm led to believe.

Sorry if this info is not what you requested.

Thai

[michele]

I,ve been told if you don't use it Ralph you loose it ?

[david lloyd]

John Keats - 2007-07-19 11:26 AM

 

Some technical knowledge is needed here I believe on the use and safety of batteries when not in regular use.

 

Is it better to allow batteries to loose charge to around half before re-charging ........... or keep them fully charged all time.

 

Does this depend on battery age?

 

What is the allowable time span from the manufacturers first full charge to being sold in a shop ( 3 years ? )

 

Does the battery have a limited life regardless of use, or not ?

 

Does it depend also whether or not the battery charger is an 'intelligent' one that reduces the charge and c onditions the battery without damage?

 

Regards, David

[Clive]

It all depends!

Lead acid batteries are best kept topped up. If left in a discharged or partially discharged condition they will deteriorate quicker.

"float" charging batteries requires a lower charging voltage to stop batteries gassing to much, but this voltage will not fully charge a battery.

Older chargers in motorhomes provide a similar output to that of the vehicle alternator, a compromise voltage of 14.0 volts. Its a bit high to use this voltage 24/7. Float voltage being in the region of 13.6 - 13.8 volts.

Later intelligent chargers take the battery to a higher voltage to enable a quick and full charge then reduce the voltage to near the float voltage.

Precise voltages are different for wet cell and gel cells. Chargers normally have a selection switch or link somewhere.

Wet cells giver best vfm if properly maintained.

?Hope that helps

c.

 

[Dave Newell]

Let's not get confused between different types of battery here. First of all laptop batteries always used to be Nickel Cadmium (NiCad) but more and more are now using Mickel Metal Hydride (NiMH) or even Lithium Ion (LiIon). Of those three NiCads are the ones that should be always fully discharged before recharging as they suffer from a "memory" effect if only partially discharged repeatedly before recharging. NiMH batteries in general do not suffer a memory effect unless you never fully discharge them before recharging and (as I understand it) LiIon batteries suffer no memory effect whatsoever.

 

Lead Acid batteries, and that includes Gel types, do not suffer from the memory effect so it is perfectly ok to partially discharge before recharging. In fact Lead Acid batteries are, in some respects opposite to the other types in that they do not like being fully discharged, certainly not repeatedly anyway.

 

Many conventional chargers will reduce to a trickle charge level as the batteries charge state rises but will continue to charge even when the battery is full and this can cause overcharging and "boil" the electrolyte off which does the battery no favours at all. More modern chargers are of the three or even four stage type and these will charge the battery to close to its full potential capacity then switch into "maintenance mode". This mode simply monitors the battery voltage and when it drops below a certain point will switch the charger on to a trickle setting to top it up.

 

Once the full charge (or near to) is reached the charger will switch off and go back to monitoring. This on, off cycle should not "boil" the battery's electrolyte off and will maintain the battery in a fully (well as near as you can get) charged state. This will not hurt the battery unless it is left like this for an excessively long time, not likely with a motorhome.

 

The problem Ralph describes is not damage to the batteries but the actual mains unit itself which I assume means something along the lines of the Sargent combined 240V consumer unit and 12V charging system and distribution board. My guess is that this unit is not designed to be in constant use on 240V and charging the battery constantly.

 

D.

 

In Edit: Sorry Clive I was typing while you were posting.

[Ralph]

Thanks for the replies. It seems to be a consensus that only putting the mains on now and again is considered best so in future I'll adopt that practice. I might just add a cheap timeswitch to power up the charger occasionally. The opinion of hayes is that I would damage the leisure battery by keeping it on charge but at 2 years old it still hasn't had the acid level drop very much (still above the plates) so I assume it's OK. My last van had a gel battery.

 

Regarding the 2 failed units, I'm very concerned as I wouldn't expect it. The charger is fitted under the bed with plenty of air space so it shouldn't overheat. I don't own a generator so it's never been connected to one. Are these things prone to failure? as they are very expensive!

 

Also does anyone know if I can get a circuit diagram? Might be useful as I would attempt repair if it wasn't a warranty job

 

I've added a picture so there's no confusion about the type.

 

[Clive]

I have the data sheet for this unit. PM me your email address and I will send it to you as a pdf. It doesn,t say a great deal but its better than nothing.

 

However Schoudt are normally a quality supplier of electrical components for the leisure market and I would not expect repeated failures, especially if the motorhome is not actively in use but just being used to top up the battery. Do you have anything on your mains supply that could be causing high voltage transients? Like large electric motors or a welder perhaps?

 

C.

 

 

 

[Clive]

lets try an experiment!

 

No cannot attach a 200k pdf!

[Thai Bry]

Ralph

Like clive, I think this is the same as in our Hymer. I'll get a pdf done from work. If you e-mail me your address I'll e-mail you the pdf from work in the morning.

Thai

[Ralph]

Clive - 2007-07-19 3:06 PM

 

However Schoudt are normally a quality supplier of electrical components for the leisure market and I would not expect repeated failures, especially if the motorhome is not actively in use but just being used to top up the battery. Do you have anything on your mains supply that could be causing high voltage transients? Like large electric motors or a welder perhaps?

 

C.

 

 

 

That's obviously the way they are thinking too as they suggest the surge protection but no. It was last used on a site in Brittany and I then spent 3 nights on aires before returning home. I plugged in at home but didn't notice anything until a few days later when the low voltage warning light came on so I don't really know when it had failed.

Everything works OK (from the battery of course) but the unit is not putting out any voltage to the battery. Most obvious thing would be a blown fuse but they are all OK. I don't know if there are any internal ones but I doubt it.

As they cost so much I'm concerned but relieved to see you say that they are usually OK. Perhaps I've been just unlucky and I've made the MTBF better for the rest of you ;-)

 

 

[Clive]

PM recieved, data sheet sent. Good luck C.

 

Just been thinking.

At a recent show I looked at a new MH with had one of these units. It did not charge the leisure battery from the car alternator. The problem was a fuse. It looked perfect but was open circut when tested with a meter.

Have you measured your fuses?

C.

 

[Frankkia]

Hi

 

We have had several 'vans with the same Schaudt charger and generally they have been very good. Normally when the 'van is at home it is on hook up all the time and has not had a problem.

 

The only one to have failed stopped working after having been on a site where the voltage dropped quite a bit as the site was crowded and everyone seemed to be using fan heaters to stay warm. The failure was in fact an internal "slow blow" fuse which had overheated. This was odd as the circuit diagram showed that it had a thermal auto reset fuse! So I suggest you whip the cover off and check to see if yours too has a slow blow which has blown.

 

Oddly enough it was Hayes who replaced ours on our first Frankia (before there was an official importer in the UK). As their guy was busy I pulled out the old unit and put the new unit in in their workshop - it was then that I discovered the burnt out fuse.

[Ralph]

Clive - 2007-07-19 5:38 PM

 

Have you measured your fuses?

C.

 

'Fraid so. Just to be on the safe side I even checked ones that were marked up for exterior light etc. just in case the labels were wrong. If it's a blown fuse I don't know where it is. And yes, I did use a meter not just look at them.

 

 

Bernie,

 

Thanks for that. As Hayes are going to replace it I won't touch it this time but I want to feel that I understand it better for any future trouble.

I did have the voltage drop when using hookup on the aire at Honfleur but that was about a month before it went wrong so just co-incidence I guess.

 

 

 

[Ralph]

Well the way I read this it seems that I can leave the charger on all the time as it drops to a trickle charge. Is this correct or have I misunderstood?

 

[citroennut]

hi, i have always been connected at home, keeps fridge fresh and cold as well as the beer! i know what you mean about the cost as mine blew when on holiday there in france - pulled a plug out and caused a spike in the mains - blew the block and two pcb's before the trips cut in.

simon

[Clive]

Yes it ends up at float charge as you say but a few bad stories seem to be comming out the woodwork!! You are not alone so it seems.

 

[Thai Bry]

Ralph

Data sheet on it's way when I get to the office in the AM

Good luck, hope it's what you wanted, let me know if I've got the right info for you.

Thai

[g4oip]

I leave 2 chargers runing 1-doing the M/H via. the ex. plug and this is on a timer for 2 hours per day [can adjust if necessary] and checking the voltage from charger it never goes above 13.8V so it is in line with many modern chargers that cut off before gassing voltage==about 14.1-4V.2- A fullu auto charger connected under bonnet to keep the service batt. fully charged again 2 hours per day.Any voltage below about 12.5V causes sulphation and this is bad news so keep 'em up.However I have found a problem with my battery as it has a multi-connector covering 2/3 of the screwed level plugs --anybody know the the best way to remove this for checking as I have not checked the level for 6 months-but I have worried about it//

Alec

[Brian Kirby]

We had a similar unit on our Burstner.  When we were at home it was always connected to mains, and when away generally connected to a site hook up.  It was thus more or less continually on mains power for about 21 months, in France, Spain, Portugal, Italy and Germany as well as in the UK.  Doesn't prove anything, of course, but there was no indication of any malfunction in all that time and I doubt all supplies were consistently 230V! 

Since you're on your third unit, and the faults appear to have arisen while you are at home, this does suggest there may be a supply oddity in your area.  However, as leaving the unit more or less continually connected seems not to be directly harmful of itself, and since a surge protector is being suggested, I wonder if the unit is sensitive to input voltage variations.  If that is true, connecting via a timer would reduce the risk, but not eliminate it, since the surge (or whatever) could as easily arise when the power is on and when it is off.  Equally, it could arise wherever you are. 

I note the unit is rated at 230V and not, for example 200-250V.  I wonder if it would be worth checking with the manufacturer whether they have any further comments to make. 

Final thought, is it possible that anything you use in your van may be causing spikes on the mains supply within the van, or even, if you are in a rural location and fed via a pole transformer, whether anyone else fed off your transformer is causing spikes, maybe farm machinery, or someone using welding gear?

[icdsun]

Ralph

 

You could use a Belkin type Surge Protector on the supply to the MH, this would give some protection from your household mains, simply plug your Hookup cable into it at your supply end, if there are any spikes/surges it should trip before it can do any damage.

 

Have you asked the manufacturer what is their recommended usage for this particular mains unit product

 

Chris