Burstner solar connections

Owlhouse

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Had my new Burstner for just over a year now ( old one now residing in NZ) an found the starter battery was not being charged by the factory fitted solar panel. The leisure battery was fine so I questioned this with the dealer and was told that this is normal. The panel is connected to the ‘Aux1’ point on the Electroblock charger and will only charge the leisure battery in this configuration.
I contacted Schaudt who make the Electroblock charger and asked if there was any reason not to use the solar connector point and they said no, it should be used.
I made up a cable using the correct plug and decent size wire, removed Burstner cable and fitted mine and now have a system that keeps both batteries charged.
If you are going to do it yourself make sure you disconnect the solar panel first then do the cable! The wiring is simple - positive cable goes to top two contacts (2 & 3) and negative to bottom contact (1). The plug was obtained from Apuljack (apuljackengineering.co.uk) but there should be plenty of other suppliers around. The cable is crimped on so make sure it is secure and the other ends go to the solar controller pos/neg.
I have kept the burstner cable in case of warranty claims just in case they complain! Refitting will only take a couple of minutes.
 
My Electroblock has a solar connector but that only charges the leisure battery. The mains charger does trickle-charge the engine battery, but not the solar input (which I don't use in any case). But it is a very old model

Which model of Electroblock do you have?
 
It is a 630. Does your solar connector have three points, if so check the wires use all three. There should be one negative and two positive if it is like mine but please check the manual first. Contact Schaudt online if you are unsure, they were very quick replying to my query even in English.
 
Looking at the 630 circuit diagram, the solar connections are: 1 negative.
3 is connected to the Aux charger 1 and Aux charger 2 connections through a 20A fuse (so far so good).
2 seems to be connected to the starter battery when the SCR cuts in. [Later] No, all the time. Connected to pin 3 when the SCR cuts in [/Later]
I don't quite understand what the difference between connections 2 and 3 are in the solar controller (don't have a circuit diagram for that), but it certainly doesn't look right to join them together.
I hope I've misunderstood what you've done.
 
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Mine has two solar connection sockets. One for the solar panel, the other for the solar controller. They simply connect the panel to the controller, the controller to the LB. Nothing clever there at all.
That’s fine if all you want is the LB charged. My point is the Electroblock system is capable of charging both batteries but for some reason burstner didn’t connect it in the most efficient way. Also, there could be a problem if your vehicle charger thinks the battery is fully charged because the solar panel is giving a ‘full charge’ voltage then it may not provide any more than a trickle charge even though the battery may be well down in its charge state - but that’s another discussion!
 
You have missed my point, because on re-reading it, I wasn't clear. Sorry.
I'll try again:
Connection pin 3 goes to the leisure battery (WB in German) (by being connected in parallel to the built-in charger, to aux 1 and aux 2 charger connections).
Connection pin 2 is connected to the starter battery (SB in German). It is also connected to the Leisure battery when the SCR cuts in.
You REALLY don't want to connect pin 2 and pin 3 together because that connects the two battery banks together all the time.
Some solar controllers have two outputs: one for the LB and one for the SB. That's what those connections are for.
Joining them together really is a very bad idea.
 
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630.png
Couple of notes; the unlabelled connection with the 50A fuse on the right is the starter battery. The things labelled "Polyswitch" are fuses.
 
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Looking at the 630 circuit diagram, the solar connections are: 1 negative.
3 is connected to the Aux charger 1 and Aux charger 2 connections through a 20A fuse (so far so good).
2 seems to be connected to the starter battery when the SCR cuts in.
I don't quite understand what the difference between connections 2 and 3 are in the solar controller (don't have a circuit diagram for that), but it certainly doesn't look right to join them together.
I hope I've misunderstood what you've done.
I think there’s more circuitry in the Electroblock that is not shown but basically Aux 1 will charge the LB, Aux 2 will charge the Starter Battery. If you connect to the solar plug instead using the solar controller +ve to pins 2 & 3 and -ve to pin 1 (Electroblock 630 ) then you have both batteries connected for charging. A bit confusing on the cct diag as the pins on the Electroblock itself are top to bottom 3-2-1 and not as shown 3-1-2 as it looks like on the diagram.
What I have done Is NOT using the Aux connections and the solar instead. You could of course connect the solar controller to both Aux 1&2 and it may achieve the same thing but the solar connector is there for that purpose. The Electroblock charger does use some ‘intelligent’ circuitry to share the charging so I prefer to use what is provided on it.B23C69CB-210D-4A9E-85F9-72C9AEEC32D9.jpeg
 
When I asked Shaudt about this their reply was it is how it should be connected. The cct diag is a simplified one and I think it does separate the two batteries. They are the manufacturer and seeing how my system behaves I am quite happy with it.
 
Your diagram is the same as mine, but better labelled!
Sorry, but your faith in the magic inside an Electroblock is misplaced. They are just connection blocks with a few fuses and relays.
By connecting pins 2 and 3 together you ARE wiring the two battery banks together.
I can tell you. I can show you the diagram that proves it.
I can't do any more.
 
Maybe a diode (not in shown in diag. ) is isolating solar pins 2 and 3.
what's the voltage on pin 3 when pin only 2 is connected ?
 
Yes both batteries are connected when solar charging but as soon as any operation I.e. starting or mains connected the solar ‘dual’ connection is disconnected. It is the same when it is connected to mains or driving, both batteries are charged by mains power or engine alternator. All we are doing is providing a power source being it solar, mains or alternator. To my mind Shaudt know what they are doing.
 
The wiring diagram tells a different tale.
The solar connection you have added connects the two banks all the time, whether or not the solar is charging.
So when you say that Schaudt know what they are doing, do you mean the people who design the things, the people who build the things or the people who talk to customers?
At least one of those three must be wrong.
You can find out which by disconnecting the plug from the solar socket and checking the connectivity to the two battery banks.
 
What I have done Is NOT using the Aux connections and the solar instead. You could of course connect the solar controller to both Aux 1&2 and it may achieve the same thing but the solar connector is there for that purpose.
Not quite.
The Aux connections and the solar WB connection are all joined together, so it makes no difference which you use.
The second (well, the third) connection is indeed for connecting a solar controller, but it needs to be one with dual outputs. Clearly yours isn't.
Didn't you think it's odd that you have two connections in the socket if they're meant to both be connected to the same thing?
 
I used the solar socket on my EBL when I on,y had one panel but my EBL coukdnt take the output when I added a second panel. I use a Votronic solar controller which has a 1amp trickle output for starter battery so just ran a cable from that to the starter battery connection on the front(back?) of the EBL.
My van had the early DT101 control panel display which didn’t show solar so didn’t make much difference to me 👍
 
I give in! I am looking at the system wrongly and whilst the connections I proposed would charge both batteries there would be no regulation of the charge to the starter battery and as in h said both batteries are connected together during this. This could be solved by introducing a couple of diodes but it would not solve the way the starter battery needs to be topped up due the alarm etc.
The reason I am looking at the system is that I want both batteries looked after when the van is in storage and the present burstner fit only charges the LB.
I looks like I am going to have to shell out for a LRM1218 or similar solar controller.
 
I don't think it can be done with a couple of diodes, because an MPPT controller needs a power feed from the battery as well as power from the solar panels. You could use a non-MTTP controller with diodes, I suppose. But that makes little sense.
Another option would be to buy a second (cheaper) solar controller for the engine battery connection.
 

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