Solar panels

Absolutely  Spanner .... I hope your post helps those that struggle to understand

I have bypassed the EC500 and have the dual mppt controller ... all is sweet even at this time of the year

My CP says solar charge 0.3 amps, leisure battery drain 0.2 amps.  Currently in Salisbury UK full sunshine.... merry Xmas to all!

I have received more information from Sargent and the company that fitted my Cobra alarm for Marquis.  Although it is not stated anywhere for the EC700, we know during the winter months when the days are short and light less intense, the EC power control system PSU should be switched off if the vehicle is out of use and not connected to an EHU.  For the EC500 and below all the solar charge will then go to the leisure battery.  No advice is given for the leisure battery so it is assumed that the winter solar power alone will be sufficient to keep it fully charged as the battery’s only output, which Sargent say is very small indeed, will be to the tracker.  If the tracker stops receiving this input it will trigger but a built-in battery allows it to continue pinging its location every 6 hours for 3 to 4 years.   AS advise that the vehicle battery is fully charged, shutdown using the red button on the vehicle ignition and then recharged every 3 months.  The alarm takes its power from the vehicle battery which it will be denied when the vehicle battery is shutdown but the siren unit has a standby battery.  The alarm is normally activated and deactivated via the central locking which will stop working when the vehicle battery is shutdown.  Although it is not stated anywhere, we know that when the EC700 is shutdown all the solar charge goes to the vehicle battery but if the vehicle battery is also shutdown Sargent has said it will not be able to receive it.  Sargent don’t know if the winter solar charge will be sufficient to compensate for the vehicle battery's drain when it is not shutdown.  They say this is for AS to answer.  I have sent AS the question today using their on-line contact form.  I suggest others do the same but whether an answer will be forthcoming is another matter.  As no solar power will go to the leisure battery it will require re-charging presumably every 3 months as for the vehicle battery for the EC500 and below.  AS give no advice on how the batteries should be recharged.  However, the C&MC and others advise that out of use vehicles that are not jacked up should be moved regularly to prevent tyre damage.  Having experienced a nasty sidewall blowout after I hadn't been storing my caravan on axle stands, I would do this every month.  For heavy motorhomes this can only be done by restarting the engine.  Once restarted the engine will need to be run for sufficient time to warm it up and for the alternator to replace the energy used by the starter motor (winter solar power alone is unlikely do this).  This is best done on the open road rather than idling as it warms up the engine more quickly and provides a more assured alternator charge.  The latter can also recharge the leisure battery and the opportunity can be taken to connect the motorhome temporarily to an EHU.  If this advice is followed, both batteries will be fine with or without solar power.

marbarsymbol wrote:Just trying to get progress on a common problem, but "if things don't change they stay as they are" and that is not progress.

I agree that the current situation is far from ideal, but the problem is that - on the base vehicle side - customers demand more and more complex features, and almost all of them consume more power. The customer that matters to the manufacturer of the base vehicle is "white van man", whether we like it or not. So what we as motorhome buyers want is not likely to be high on their priorities.

On the habitation side, Sargent are faced with more complexity too. Two relevant examples are the need to integrate with CANbus so that their systems can detect what the base vehicle's status is, and another is the change to smart alternators, which requires more complex charging systems. And then of course there is pressure from the marketing dept. to make the system more "feature rich" to stop them losing custom to other manufacturers such as CBE.

I suspect that Sargent could be pressurised to do more to implement low-power standby modes. I don't think you can expect base vehicle manufacturers to make any useful changes at all - they will (IMO) never implement changes to accommodate a van being laid up for months at a time, because users that want this are an insignificant proportion of their market.

marbarsymbol wrote:Not everyone who stores their van remote from where they live has access to EHU or are able to visit every few weeks to give the vehicle a run. 

I don't keep my motorhome in a storage compound away from an EHU but if I did and I couldn't visit it every few weeks to give it a run I would aim to do so every 3 months which might be just enough for the batteries.  If even that was not possible I would have kept my caravan which, with a little preparation, I frequently stored for long winter periods in a storage compound without visiting it.

Peter Brown wrote:You cant. It stops working when the battery goes flat. All motorhome specs are optimised for living in them. For storage, switch off and disconnect all electrics. Security should be provided by the storage service provider.

Sargent said that even if the leisure battery is discharged there may still be enough voltage left for it not to trigger the tracker.  The tracker consumes very little power but if it needs more it has its own built in battery which will keep it working for 3 to 4 years.

Peter Brown wrote:Just do what's needed in those circumstances and disconnect the batteries. People have been storing vehicles for 100 years and that was always one of the requirements.

In effect the batteries are being disconnected when the EC power control system is shutdown and vehicle battery placed into standby mode.  That said the tracker will continue to receive power from the leisure battery and for the EC500 and below the leisure battery will receive some solar power.  All lead acid batteries self discharge which results in a build up of lead sulphate on their electrodes.  This is perfectly normal and is normally removed when the battery is recharged.  However, if the lead sulphate is left there too long it starts to harden making it more difficult to remove and therefore for the battery to recharge.  This reduces the capacity of the battery and shortens its life especially if it is a vehicle starter battery which is not designed to be discharged.  It follows that batteries should not be just disconnected and left for month on end with no charge.  The AS advice for the vehicle battery in standby mode is that it is recharged every 3 months.