Just had our 2003 Troll serviced and it was found that the voltage output from the BIP to the battery is 17v whilst hooked up to the mains whilst something around 13-14v would be expected.
It has a Scheiber 30.65100.84 BIP, a 110a Varta battery and a Schaudt booster.
I am concerned that 17v will ruin the battery, if it has not already done so, and will affect lights etc.
Does anyone have any advice as to what I can do to rectify this situation?
Can I just add a charge controller into the system similar to a charge controller fitted to solar panels?

I had the same set up on my 2002 Troll, all long since hurled into the night. As part of my upgrade, I dispensed with the Schaudt battery charger and replaced it with a Ctek offering. I don't see any reason why you just couldn't do that because the BIP has no relevance to the charging circuit, the 240v just passes through it to the Schaudt unti...

You'll gain back about 2kg of load capacity as well!!

hth...

I presume you are talking about the Scheiber BIP and not the Schaudt Booster?

From what you are saying, it is possible to disconnect the battery charger within the bip, retain the rest of the bip and install a separate charger?

I have now found this thread that may be a solution How to: Modernise Old-fashioned BIP Electrics

The Schaudt Booster is to regulate the charge to the leisure battery when connected to the towing vehicle. It has nothing to do with battery charging on EHU.

I disconnected the transformer from my BIP power pack and connected in a CTek charger for permanent battery charging. I kept the rest of the BIP unit for 230V and 12V distribution.

Great, I understand now.....seems fairly straightforward to do.
Do you have info to hand regarding which CTek charger you installed?

For those of you who have replaced the charger, is it simply just a case of cutting the main supply cable and the output cables from the transformer and connecting the Ctek (or similar) charger direct to these?

Niv2,

Changing the mains input from the BIP to the Ctek is straightforward and easy to do. Swapping the output from the BIP transformer to the output from the Ctek will not work as it is the charging circuit within the BIP unit that rectifies and controls the voltage.....and that's the bit that's not working properly.

As mentioned, JohnE had done a fully professional job for others in the past which will involve you stripping out the BIP and sending the circuit board to him to modify.

I am not a professional automotive electrician but a plain and simple engineer. I devised a relatively simple solution using the existing components in the BIP without requiring the unit to be removed or disconnected from the many connecting cables. The only extra component to buy was a cheap changeover relay for £4 to satisfy the legal requirement to prevent the awning light showing when the caravan was being towed.

My design has been in place and working all season in my 2007 Triton, but I am loathe to publish it in case there is an inherent fault that I have not spotted. I was, and am, always willing to back my own inventive skill. Others are more wary and that's ok for them too

I'm currently working on my current project, adding a warning lamp to the Truma Heater Fan. That looks more simple and I might publish that.

If you can read a wiring diagram and crimp up a couple cables I can send you my design by personal message.

My previous post might look a bit scary but maybe it is better to describe the method in words.

On the BIP, there is a switch next to the 230V isolator and I always wondered what that did. Nothing actually except if you want to power your 12v electrics from the tow vehicle when stationary.
So, we have an input to the 12V distribution system including the leisure battery that is seldom if ever used. I simply dropped out the blue input cable from the top of the switch and isolated it. Then replaced the input to the switch with the 12V output from the Ctek charger. Connect the negative from the Ctek to a suitable earth point. Disconnect the 230Vac to the BIP transformer to take that out of the circuit and the job is done. Simple I think.

There is as always the irritating inability to use the awning light when not on EHU but that's easily solved with a cheap relay. Details available on request

Ray. Very interested in your system / install.....if you are able to pm me some details would be much appreciated.

Also which CTek unit did you use.....I am thinking 7.0 as this seems to be able to act as a power source also.

I was thinking of simply disconnecting the transformer and connecting the output wires from the CTek directly to the battery terminals....it seems to me that that would work?

This is the approach I took..

Question for Eriba Electrical experts??

Though I don't quite understand where the photos have gone.. If need be, I could repost them in this thread...

Nev2, I think mine is a 3.6, marginal for a 110Ah battery but seems to do the job. I'm on solar on pitch anyway, the Ctek is mostly for when I'm at home and all through the winter.

Looking at my wiring diagram, I can't see why you can't connect the cTek directly to the battery and still enjoy your 12Vdc devices at the same time. It's easy enough to try it and see. I can't actually see why it wouldn't work, can't see any leakage path through the old BIP circuit to stop it charging your battery properly. Again, I bow to superior knowledge if there is a potential problem.

Once you have the mains disconnected and the cover off the BIP, it's easy to see how to disconnect the transformer and connect the cTek up to the same terminals......as opposed to using the 13amp plug of the cTek to connect to the mains. Cut that plug off and crimp on a couple of connectors

Ray. Thanks for feedback......looks fairly straightforward so think I will give it a go. Will probably use the CTek 7.0 as more robust and can be used as a power source. Does not seem to be any point in removing / replacing or modifying the rest of the BIP.....would be just making more work for the sake of it, so it seems.

I also found this review of the CTek MXS 7.0 where it is recommended as best by Practical Caravan https://www.practicalcaravan.com/reviews...battery-charger