Newbie to MH - advice please

My van is stored at home and is plugged into the mains for at least part of the day. Quite a few years ago Peedee recommended the Battery Master to me and I have had them fitted to both motorhomes as the internal 230v system does not charge the vehicle battery and they just take away the worry about keeping both batteries in good condition. They seem to be a fit an forget solution. 

David

Obviously if you had a 120W solar panel on the MH you’d use that to charge the leisure/starter battery. The Battery Master requires a power source so it’s either EHU, solar or frequent alternator charging. My preference would be a solar panel (min 150W) on a split charger. I like the idea of free electricity unconstrained by grid supply and, in my case, it works fine 100% of the time irrespective of whatever the climate in SW England delivers. Just checked the sensor on my tracker this morning (sunny intervals) and starter battery is getting 14.99V

The amount of charge allocated to a battery by a controller will depend on a number of factors but the biggest must be the current state of charge (is it low or nearly full), the load on that battery (are devices running against it) and the available power.

With the van on the drive, my batteries are nearly full all the time (no habitation electrics and just the draw of the alarm/immobiliser) so the requirement is small (but enough to flatten a starter battery in a few weeks without support) and there fore the input from the 300w solar appears to be small.

turn on loads of lights or an inverter with a bike charger attached and only then will you see what your solar system can (or can't) do.

Hi,

Our vehicle battery will trickle charge once the leisure batteries are full, but only on EHU. When not "Plugged In" The solar regulator will keep the leisure batteries topped up only.

I guess its down to if your van is on the drive or away in storage, but rather than spend a few quid, If its possible I'd just take it a run round for 30 mins once a week. 

Ours is kept in storage, but I'm lucky that its only five mins away so Its easy for me. I have a regular circuit that's 15 miles, with a mix of urban/national speed limit roads and I don't have any problems.

As per comments from the other guys, your voltage readings are perfectly normal. Our vehicle battery is normally 12.2/12.7V after its been stood for a week to ten days.

Matt

Matt, with fuel prices as they are, you're definitely 'spending a few quid' every time you hake it out for that 30 min run...

if you off grid, it might be worth the small investment to add a Battery Master to ensure your cab battery is fine after a few days....or more...where your leisure batteries are fed by the solar regulator....you could even swap the regulator for a dual output version.

“…..Matt, with fuel prices as they are, you're definitely 'spending a few quid' every time you take it out for that 30 min run...”

With a gallon of diesel around £6.75 a gallon, a 30min run each week is probably costing upwards of £13.50 a month or £162 pa just to charge the battery. That’s quite expensive when you consider solar is free. 

Its a bright day today, the sun is out but still quite low in the sky (probably about 10 o'clock). My 120w panel was only just maintaining float voltage of 13.6v. It should be between 13.5 to 13.8v to maintain a full battery. Yesterday was a gloomy day and it was showing only 13.3 volts. I use a NASA Marine BM1 meter to keep any eye on my leisure battery.  You can see whether it is charging or dischrging amd to what degree plus the voltage across the termals and what capacity is available.

peedee

At this time of the year a portable solar panel has significant advantages over shallow angled (or flat) roof mounted panels as you can achieve a much better orientation and inclination.  In winter when the sun is low in relation to the horizon, a steep angle of about 65 degrees is best in Bedford. 

Off topic I know but have to say what a clean looking roof peedee.  Photo is reminding me to go out and ensure our solar panel is clean.

I cleaned it today but it doesn't look as good as in the photo because all I did was wash it. Too cold to be out there for long. The photo was taken after a wash and a polish.

I didn't have enough roof space for anything larger than a 120w panel.

peedee