I have an 1985 Estrel folder. It Has a 12v transformer underneath and a small box with a plunger inside the van.. When the van is pluged into the mains and the battery is also conected. The plunger pops out and disconects the battery. Any one know why this happens?
The plunger is the overload reset button - obviously pops out on overload. There are two reasons for it to pop out in your situation, one is that the component has become weak with age and needs replacing, the second is that the battery is very flat, or completely 'cream crackered'
Give it a try with a decent battery to see if it does the same.
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Hi thanks for the reply, The battery is new and I keep it well maintained. I have spent a few hours trying to understand the wiring I have 2 x spageti junctions to work out. What is happening is when the battery is conected it is supplying the 12v cuircuit. When the van is plugged into the mains. The transformer then is turned on and is trying to supply 12v. this is when the plunger trips. This disconects the transformers input And the battery becomes the main supply. If I disconect the battery and reset the trip it all is ok. The transformer then becomes the main supply. It is a bit hard to put into words. If you could see it you may understand it more. I think it is apossing currents meeting in the middle. I was hoping someone on here may have the same setup.
No worries about opposing currents, this is the way the set up is supposed to work.
Providing that the transformer/charger is connected to the battery the correct way positive to positive and neutral to neutral then either the battery is duff (and even new ones can be) the overload cutout has become weakened or your circuits are overloading the transformer.
Try removing all the fuses to remove any load from your circuits - lights, pumps, etc. and then connect it to the battery again, if it still trips then the problem is with the battery circuit or battery. If it doesn't trip then I'd say your fault is a weak overload cutout (the red button).
------------- Caravanning is a way of getting a cheap holiday out of an expensive hobby