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When using solar panels or generators I can see using a stage charger is a good idea. However in the main solar panels use a pulse and measure voltage decay, as there is a problem with stage chargers, they measure the charge current to work out when to drop into final stage, so if the battery is being used, it can delay or stop the charger dropping into final stage.
BS7671:2008 gives a maximum charge voltage of 14 volt, so stage chargers don't comply, however many caravans fitted with them as standard.
To my thinking when I return home the battery has all the time in the world to recharge, so although I use a stage charger one not required, and two does not matter anyway as nothing being used in the caravan.
On site without 230 volt clearly not using charger, with 230 volt no hurry to recharge. I can see touring one night without power next night with it, you may want a fast charge, however I have to use motor mover for around 60 yards to get caravan into garden, removing the battery for charging after, even with a stage charger with just 3.8A charge rate at stage 1, it takes just 12 minutes before at stage 2 at 3A and that only last for another hour before stage 3 at 0.8A and then around 8 hours before dropping to 0.1A, this is a 75Ah battery.
So with a caravan built in stage charger able to deliver 25A, the time at high rate must be very short.
So what will 14.8 volt rather than 14 volt do to 12 volt equipment in the caravan? I would guess most stuff designed for cars will be OK, although tungsten bulb life with be likely shorter, proper caravan LED's will be OK rated 10 - 30 volt DC, but house hold cheap LED's will not like 14 volt never mind 14.8 volt.
And although at 3.8A the Lidi charger I use when I remove the battery is unlikely to cause the battery to gas, at 25A stuck at stage 2 because the caravan lights are using at least some of the 3.8A at which point the charger drops into float stage held at 14.8 volt very likely the battery will over heat and gas.
So what have I got wrong? Why are stage chargers fitted as standard to caravans? narrow boats I understand, you have 480 Ah of battery not 110 Ah or less, and even with 2 alternators feeding a alternator to battery charger able to pulse charge at 120A often engines are not running long enough to recharge the battery, so on the odd time when you do get a shore supply you really do want to recharge the batteries quickly.
But as yet not seen a caravan with a washing machine built in, or microwave running from inverters, 110 Ah batteries are simply no big enough for that. And with narrow boat in morning you can start to travel while some one else is cooking, can't do that even with motor caravan.
So why fit stage chargers to caravans as standard, what have I missed?
BS7671:2008 gives a maximum charge voltage of 14 volt, so stage chargers don't comply, however many caravans fitted with them as standard.
To my thinking when I return home the battery has all the time in the world to recharge, so although I use a stage charger one not required, and two does not matter anyway as nothing being used in the caravan.
On site without 230 volt clearly not using charger, with 230 volt no hurry to recharge. I can see touring one night without power next night with it, you may want a fast charge, however I have to use motor mover for around 60 yards to get caravan into garden, removing the battery for charging after, even with a stage charger with just 3.8A charge rate at stage 1, it takes just 12 minutes before at stage 2 at 3A and that only last for another hour before stage 3 at 0.8A and then around 8 hours before dropping to 0.1A, this is a 75Ah battery.
So with a caravan built in stage charger able to deliver 25A, the time at high rate must be very short.
So what will 14.8 volt rather than 14 volt do to 12 volt equipment in the caravan? I would guess most stuff designed for cars will be OK, although tungsten bulb life with be likely shorter, proper caravan LED's will be OK rated 10 - 30 volt DC, but house hold cheap LED's will not like 14 volt never mind 14.8 volt.
And although at 3.8A the Lidi charger I use when I remove the battery is unlikely to cause the battery to gas, at 25A stuck at stage 2 because the caravan lights are using at least some of the 3.8A at which point the charger drops into float stage held at 14.8 volt very likely the battery will over heat and gas.
So what have I got wrong? Why are stage chargers fitted as standard to caravans? narrow boats I understand, you have 480 Ah of battery not 110 Ah or less, and even with 2 alternators feeding a alternator to battery charger able to pulse charge at 120A often engines are not running long enough to recharge the battery, so on the odd time when you do get a shore supply you really do want to recharge the batteries quickly.
But as yet not seen a caravan with a washing machine built in, or microwave running from inverters, 110 Ah batteries are simply no big enough for that. And with narrow boat in morning you can start to travel while some one else is cooking, can't do that even with motor caravan.
So why fit stage chargers to caravans as standard, what have I missed?
