Mains charging batteries?

[DickB]

My Adria has the Nordelettronica NE219L control panel and the NE237 charging module. The instructions say that it may be connected permanently without damage to the batteries which is the same as the system on my boat which had solar panels permanently connected (in the Med) with no damage over many years. However, in previous posts it has been suggested that the charger on a motorhome shouldn't be connected permanently. Do I follow the instructions and leave power on permanently?

When the control panel is switched on and mains is applied the mains connection light illuminates, but when it is off there is no indication. Are the batteries still being charged when the unit is off but power is applied?

 

Advice please

 

Dick

[arthur49]

DickB - 2018-07-17 9:46 PM

 

My Adria has the Nordelettronica NE219L control panel and the NE237 charging module. The instructions say that it may be connected permanently without damage to the batteries which is the same as the system on my boat which had solar panels permanently connected (in the Med) with no damage over many years. However, in previous posts it has been suggested that the charger on a motorhome shouldn't be connected permanently. Do I follow the instructions and leave power on permanently?

When the control panel is switched on and mains is applied the mains connection light illuminates, but when it is off there is no indication. Are the batteries still being charged when the unit is off but power is applied?

 

Advice please

 

Dick

 

Check this out. Allan of AandN is on here regularly http://www.aandncaravanservices.co.uk/ehu-full-time-yes-or-no.php

[aandncaravan]

Dick, you say it suffered no damage, but do you mean you noticed no obvious damage?

It might have lasted years, Boat batteries do, but could they have lasted a whole lot longer?

 

 

Long time since I repaired an NE237, but I think when you turn it off, you deactivate the charger. It is the charger 12v output that is used to illuminate the 'Mains connected' light.

 

 

 

A similar question to mains long term charging was asked recently about Solar long term charging and this, more up to date reply than the web page above, was posted. Obviously Solar and EHU long term charging are similar.

 

 

 

"I think it depends the the efficiency of the Solar set-up and the batteries used. Some batteries will half tolerate long term over charging ok, others will be damaged quite quickly.

 

The Yuasa website states that Leisure batteries kept on a permanent 'float'/'trickle'/'maintenance' charge, "will result in internal degradation of the battery". Even when used with, "a well-controlled charging system".

As a result they suggest that batteries treated this way should be regarded as having a maximum two year life. See this extract :

 

Battery Maintenance in Non-Automotive Float Applications

1.Typical applications are motor-generators, stand-by applications etc. The Leisure Battery range is recommended for these applications; standard vehicle batteries are not suitable.

2. Batteries used in these applications should be changed every 2 years or more frequently. (Continuous charging, even from a well-controlled charging system, will result in internal degradation of the battery).

 

For full text read here : http://www.yuasa.co.uk/info/technical/need-know-batteries/

 

 

 

Additional evidence to support things are not well with all Motorhomes in this respect is the tale with Banner Energy Bull batteries.

The Banner Energy Bull Wet battery seems to be prone to fluid loss in normal circumstances, but this seems to be much worse when on long term charging, either by connection via EHU or Solar power.

 

Back in 2014 the Roadpro website was stating that the Banner Wet batteries were Maintenance free,

 

“Banner Energy Bull” batteries don’t require maintenance in normal use"

 

However, as of November 2016 the Roadpro website had changed to warn of high fluid loss when used :

 

"'...... with a solar panel, a battery to battery charger or a mains charger that's on for days at a time, the electrolyte levels of Energy Bull batteries must be checked on a regular basis".

 

Normally, excessive fluid loss is a sign of overcharge, losing a lot of fluid when on Solar and long term mains charging is strong evidence that long term charging from Solar/EHU affects batteries.

 

While the Banner Energy Bull has clearly been highlighted, the issue affects almost all Habitation batteries to some degree or other.

 

 

Note also that as of 07/04/2018 the Banner website was stating that their Banner Running Bull AGM batteries should not be left on charge for idle periods longer than 7 days at a time or the battery life will be shortened, even on a low float voltage. The FAQ page has an item :

 

"What values should I use when setting an external charger for AGM batteries in the caravan? How high should the charging and float charge voltage be?

Please employ the AGM setting, which means that the charge voltage should be set at max. 14.8V and the float charge voltage at 13.5V. Best of all, use an IUoU characteristic with temperature compensation (should you have this setting available). In order to obtain the maximum service life from your battery. Please "ensure complete separation" from the on-board supply (charger) when the vehicle is not in use >7 days.

 

The Banner Battery advice re AGM batteries is reiterated by almost all big battery manufacturers, that AGM have short lives on long term EHU or Solar..

 

 

If you want more evidence -

Victron Energy are also suggesting that the 13.8v charge voltage of the average motorhome charger will shorten a batteries life. The 'Victron Energy Unlimited' document suggests a maintenance charge of just 13.0v - 13.2v. So a permanent 14.4v looks dangerously damaging?

 

In installations where batteries are kept on permanent charge, like UPS battery backed installations for Hospitals, Data Centres, etc the recommended maintenance/trickle voltage from the Battery manufacturers is between 13.0v and 13.2v.

 

 

Schaudt's latest LRM1218 Solar Charger has dropped the Maintenance charge down from the previous units 14.2v maintenance charge to just 13.4v.

 

 

Victron Energy's own new range of chargers now Maintenance/Float/Trickle charge at 13.2v, suggesting as per other documents now surfacing, that long term Solar/EHU at the usual Chargers 13.8v (or higher) will have consequences".

 

 

[DickB]

Thanks for the responses. I sort of assumed that when the system is switched off there would no charging. My plan was to use a time clock to switch on mains for 24 hours a week during the winter but this would require the power in the van to be left on permanently with a consequent permanent drain. As the instructions specifically state that power can be applied permanently without damage I will probably do that.

Re using solar permanently on my boat, this has worked fine for some 25 years. Leaving a boat unattended for around 7 months over the winter definitively needed solar power to be applied or they would have been completely dead by spring. With 120w panels the 400Ah batteries lasted over 6 years on average, so the regulator did its job and overall it certainly worked for me.

 

Dick

[Billggski]

So......if I have switched 12v off on my control panel, is it still charging when on hook up?

[Derek Uzzell]

The rule-of-thumb seems to be that battery-charging occurs irrespective of whether the control-panel is turned on.

 

My Rapido’s battery-charger is easily accessible and has an illuminated On/Off switch. If I connect the Rapido to a 230V power-supply, turn on its control-panel and the charger’s On/Off switch is in its On position (with switch illuminated) a little LED on the control-panel will be glowing and the panel’s voltage readouts for the starter and leisure batteries will indicate that they are being charged. If I then switch off the charger (On/Off switch not illuminated) the liitle LED on the panel goes out and the voltage readout values reduce indicating that charging is no longer occurring.

 

This to some extent comes down to trust (“Belief” is not something I’m endowed with!) and the simplest way to be sure that your batteries continue to be charged with the panel switched off is to use a multimeter to confirm they are being charged with the control-panel switched on and that they continue to be charged with the control-panel switched off.

[aandncaravan]

Billggski - 2018-07-20 8:43 AM

 

So......if I have switched 12v 'off' on my control panel, is it still charging when on hook up?

 

 

That would depend on the unit, the NE237 is an unusual, integrated, all in one unit, usually only fitted in a few models of Adria

As I said above,

 

"Long time since I repaired an NE237, but I think when you turn it off, you deactivate the charger. It is the charger 12v output that is used to illuminate the 'Mains connected' light".

If you turn it off in the 'normal' way it still draws quite few milliamps. 50ma I think?. But if you hold in the 'Off' button for longer than 5 seconds it drops down to 4ma, or something like that. My last Ne237 repair was about 4 years ago, wouldn't do one agian.

 

 

As Derek notes, some motorhomes use a Standalone charger, which operates independently of the rest of the electronics, such as the CBE and Sargent 151, PX300, Nordelettronica NE143, etc.

 

Schaudt Elektroblock's will charge the battery even when the manual states it is 'isolated from the battery' because of a German to English translation issue. What the manual means is isolation of the devices from the Elektroblock, the Elektroblock charger is always connected to the battery.

If EHU is connected the Habitation area and Starter batteries will be charged.

 

 

On some Sargent units like the ECxxx series, if the charger is 'On' but if the power distribution ECxxx unit is turned off it will still charge the habitation battery but you may lose the 'Smart' charge functionality that keeps the Starter battery topped up. The main controller needs to be on for the 'Smart' function to work.

On some Sargent models this also applies to Solar charging that uses the Smart feature.