A simpler replacement method has come up, if you arn`t to fussed about charging both the MAIN starter battery and the LEISURE battery at the SAME TIME. You just need the above charger without any modifications, and a 3-way switch, centre-off position. Connect the POSITIVE 12V output from the charger to the centre terminal on the switch, then the original red/black wire to one side of the switch, and the red/yellow wire to the other side of the switch. When the mains charger is on, you just switch the charging current either to the LEISURE battery, or switch the other way to charge the MAIN battery. Simple.
The main battery will usually be charged up fully from the alternator anyway, but it`s useful to be able to charge it from a mains charger when required, for example, if it`s been stood over winter and you want to boost up the battery a bit. Otherwise, leave the switch in the position to charge the leisure battery.
Once you`ve done this, just test the charger is actually charging your batteries, do this with a meter and check the battery voltage BEFORE switching the charger on (you have got the hook-up plugged in havn`t you! ) and then check the battery voltage AFTER switching on the charger, you should see a jump in voltage (depends on how flat your batt is obviously) but from 10V-12V it will jump up to 13.5V when the charger is working. Then CHECK THE MAIN STARTER BATTERY the same way, before charger and after switching charger on.
You can also do a quick check for charging the LB by watching the battery level indicator on the kitchen block. Switch it on with the toggle switch,you will probably have a yellow LED lit for battery level, when you switch the charger on it will jump up to green virtually straight away, this shows the charger is working.
This is also useful to test whether the engine is charging the LB, swith on the indicator with the engine STOPPED, will probably show a yellow LED (unless you`ve been chrging it up all night !) then when you start the engine the LED will jump to green, this shows the alternator is chrging the LB. Multimeter on the relevant battery is the most accurate.
Switch I used from here, capable of taking the current
http://www.ebay.co.uk/itm/On-Off-On-Heavy-Duty-Toggle-Switch-25A-Change-Over-/160518943268?pt=UK_CarsParts_Vehicles_CarParts_SM&hash=item255facb224" rel="nofollow - http://www.ebay.co.uk/itm/On-Off-On-Heavy-Duty-Toggle-Switch-25A-Change-Over-/160518943268?pt=UK_CarsParts_Vehicles_CarParts_SM&hash=item255facb224
mounted it next to the charger
------------- Sunny Lancs
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