PS You should consider VIP Membership to this forum for all the help from other members! It will also open up access to much more T6 information too. 
Hi thanks for that,
This is the solar: FLEXi SUN – 150W Flexible Solar Panel | CampervanCulture.com
This is the MPPT (bluetooth enabled): Midsummer Energy
Whilst I 100% understand the performance is worse in the winter, its important to read these recent posts in the context of the first and second page of this thread, which show even in great conditions in the summer, the setup wasnt producing a lot, nothing like what others were posting on those pages for the same time period. I think this is going to be my issue at this time of year. Even if I do fix it, how will I actually know! lol
Thanks...
Hmmm. Difficult to know. Not sure I would trust a solar panel supplier who only uses vague 'nominal' values. My guess is that it is a 130W panel under normal standards but I have no experience of that brand. It is only two thirds the price of a good brand equivalent 150W panel. Maybe another member has used one?
The MPPT is OK. Victron are an excellent brand of MPPT Controller. You only have a 10A version but that is OK for your panel. The controller would limit any charge to 145W if it ever got that high!
Thanks @Dilbert,
At the time I ordered, I literally had no idea of the different brands and suppliers, so went with the recommendations of the converter (the converter themselves had good reviews), I trusted them on specific product selection. So I specified a 150W panel and they selected the appropriate things.
So, the converter has accepted the panel and MPPT are not working correctly and has agreed to replace both items. The van is booked in on 4th Jan for the old to be replaced with new. I am wondering based on your comments, if I should ask him to upgrade the setup instead of replacing "like with like" (old for new), and I pay the difference between the two setups.
If I were to do that, would anyone have any recommendations of which panel / MPPT controller I should ask him to fit? And what rating, should I be going above 150W?.
In case it helps, these are the "electrical things" I have in the camper.
Thanks
You will need an MPPT controller that can handle the size of panel you select. You may have to go up to the 15A or 20A version of the controller you have: SmartSolar MPPT 75/10, 75/15, 100/15 & 100/20 - Victron Energy
As far as solar panels are concerned, there is a lot of information on this forum. The search function is your friend! For example: https://www.t6forum.com/threads/solar-panel-selection.22620/
Best way forward as above - converter replaces. There is obviously something going on that we can't pin down via the forum, dodgy joint, something blown etc.
Just a thought, which may have been covered, when your engine is running have you looked at your bluetooth monitor to see what is going to your leisure battery. I would expect 14v or so and 10 amps or so especially as your battery voltage on the monitor is quite low on some screenshots. I think an earlier post you said that after a reasonable drive your battery was low voltage and fridge turned off with flashing lights. This is to prove your charging circuit from the alternator is working ok.
Then the solar charging issue, we are all just guessing as I thought the converters had changed the panel and controller already. They have decided they are faulty and will change so until that's done the same fault will keep occurring.
If I read your chart correctly you will consume about 50ah per day which has to be replaced by solar when off the grid (ehu).
You ideally want a panel/controller setup that exceeds this as you dont get perfect sunshine hitting the panel for many hours each day so the bigger the better in my opinion.
I have a 150w redarc panel on the roof and a 150w redarc blanket that I connect when needed and sometimes that only just replaces the power used, due to clouds and rain etc.
As I live in Australia I am reluctant to advise anyone here on panel sizes as members in the UK know the local conditions and how much panel wattage needs to be to top up battery consistently each day.
You will know when this is fixed when you can see the current and wattage changing on your battery monitor when your panel is in the sun. You shouldn't see 0w and 0 amps as you do at the moment.
Then the solar charging issue, we are all just guessing as I thought the converters had changed the panel and controller already. They have decided they are faulty and will change so until that's done the same fault will keep occurring.
If I read your chart correctly you will consume about 50ah per day which has to be replaced by solar when off the grid (ehu).
You ideally want a panel/controller setup that exceeds this as you dont get perfect sunshine hitting the panel for many hours each day so the bigger the better in my opinion.
I have a 150w redarc panel on the roof and a 150w redarc blanket that I connect when needed and sometimes that only just replaces the power used, due to clouds and rain etc.
As I live in Australia I am reluctant to advise anyone here on panel sizes as members in the UK know the local conditions and how much panel wattage needs to be to top up battery consistently each day.
You will know when this is fixed when you can see the current and wattage changing on your battery monitor when your panel is in the sun. You shouldn't see 0w and 0 amps as you do at the moment.
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Thanks @AussieMick
Information very useful! I will check via bluetooth when I next start the van (either today or tomorrow).
Re the flashing fridge / replacement of the panel and MPPT. We established that the reason for the flashing fridge and the other voltage drops (plagued me throughout November) was an unrelated issue. Basically, the converter had used "snap on" connectors to the battery terminal posts, which due to the number of cables did not "snap on" properly. The flashing fridge issue turned out to be the negative terminal connector had just "popped off" on its own (after I hit a bump on the road I imagine). The poorly fitting terminal connector led to some debate on the thread about whether that could be the issue with the solar too. I.e. if the connection to the battery is poor (as the terminal post connector is not on properly) then this could impact the solar charge. So, I replaced the terminal post connectors with the ones recommended further up (bolt on ones), and reset everything to see if that made a difference before the converter replaced everything. Alas, it never made a difference, so we are back to "converter replaces".
Van is booked in for 4th Jan for this, and the current plan is he will replace MPPT and panel on a pretty much "like for like" basis as part of warranty. So if I do want to upgrade anything (better MPPT or better brand / higher output panel) then I will need to pick it and get back to him ASAP.
I am thinking it would be wise to go up to 200 or more, and use an MPPT which is also capable of using the increased output. So, I have a bit of a research challenge / homework on best panels and MPPT which I need to conclude in the next 48 hours really, so he has a chance to source the parts and so forth.
I have been kindly given some links to look through above re solar setups, but if anyone has any known good configurations which work well, in terms of specific products or brands, then please drop them below and I can have a look
Thanks to all for the continued help on this, much appreciated...
Cheers.
Hi @AussieMick,
Re your question about readings when the engine was running...
I took some screen shots before, during and after running the van. I turned on the lights and fridge for a while before, to draw something out of the battery, so I could see what impact going for a drive made.
Before starting the van - all electrics off just before this (so electrics off when this one was done)
Whilst van running (all electrics turned off, van running on tick-over for about 1 minute when this screen shot was taken).
After a 50 minute drive in the van (2 x 25 mins, with a 30 min stop).
Van stopped (not running), and left van for 1 minute before taking this reading.
So, it seems to me, that a 50 minute drive has moved the battery from 12.22v to 13.35. I am assuming that means that it working fine?
Does all of that look ok?
Cheers
I would expect to see a decent current ( amps) reading when your van is running. Do you have a shunt on the negative battery terminal. My battery monitor is a victron bmv712 with bluetooth to my phone and I can see whether I am putting power into the battery or using power from the battery. This is monitored through a shunt on the negative terminal. I find it strange that you always have 0 amps even when charging battery with engine running.If I am drawing power from battery with no charging I will get a minus current reading and if putting in more than I am using I get a plus current reading. First picture drawing power FROM battery. Minus current. Second picture putting power INTO battery plus current. Maybe I am just unfamiliar with your victron setup but I would have thought you could see incoming current reading. 
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Please note that @monsteruk is only using his MPPT app to monitor voltage. The current reading in this app is only for solar. He will not see the engine run charging on this!
Your BMV and app shows all current in and out of the battery so will show charging from all sources.
@monsteruk the voltage of 14.78V when the van is running looks a bit high if you have a standard lead acid leisure battery?
What type of battery do you have? What charging system do you have for engine run charging?
What type of battery do you have? What charging system do you have for engine run charging?
Ok, I was unfamiliar how his mppt was monitoring battery so that would explain zero amps all the time. Thanks for pointing that out to me, you always learn something reading these posts.
P
Phil_G
Guest
All we need now is sunshine! 
Hi everyone,
I have just had a call from the converter, telling me he now has the existing setup working (MPPT and 150W panel). He has replaced the battery (which he thinks was faulty) and replaced the rubbish "snap on" terminal post connectors with good quality bolt on ones, and now says the panel is recording much better numbers and is in his opinion functioning correctly. He has asked me to go an collect the camper later this afternoon, and I want to be able to confirm it is working ok against some independent evidence. With that in mind...
Could I ask everyone who can spare 5 minutes, to connect to their bluetooth MPPT and just screen shot the current solar charge figures from it. Could you also state:
1. Panel power (e.g. 150W)
2. Condition (e.g. sunny, cloudy, raining or whatever).
That would be really useful to me as a comparable when I collect the van later, to be able to see what it is doing, vs what other people are getting with known good setups.
Thanks again to everyone for their help. I sooo want it to be working properly!
I have just had a call from the converter, telling me he now has the existing setup working (MPPT and 150W panel). He has replaced the battery (which he thinks was faulty) and replaced the rubbish "snap on" terminal post connectors with good quality bolt on ones, and now says the panel is recording much better numbers and is in his opinion functioning correctly. He has asked me to go an collect the camper later this afternoon, and I want to be able to confirm it is working ok against some independent evidence. With that in mind...
Could I ask everyone who can spare 5 minutes, to connect to their bluetooth MPPT and just screen shot the current solar charge figures from it. Could you also state:
1. Panel power (e.g. 150W)
2. Condition (e.g. sunny, cloudy, raining or whatever).
That would be really useful to me as a comparable when I collect the van later, to be able to see what it is doing, vs what other people are getting with known good setups.
Thanks again to everyone for their help. I sooo want it to be working properly!
Hi All,
Can I check if these scales are accurate in terms of working out percentage state of charge for an AGM style leisure battery? The converter has replaced with old battery with a Hankook 59520 AGM battery, which is 95AH (old non AGM battery was 110AH, so seems like a downgrade to me, but not sure if a 95AM AGM is better than a 110AH standard battery).
This is the scale I am looking at (which states AGM).
Am I correct in thinking that if the battery was 100% charged (showing 13v) and I connected a 12v, 1amp load to it for 47.5 hours then at the end it would read 12.05v and have 50% capacity (i.e. 47.5AH) left? Are the scales accurate as I am seeing some odd figures from the battery if the scale is correct.
New battery with the new connectors in pic below just so you can see what it is, main question is about if I am interpreting the scale above correctly.
Clarifications re whether the scale in the first pic is accurate would be most welcome.
Thanks
Can I check if these scales are accurate in terms of working out percentage state of charge for an AGM style leisure battery? The converter has replaced with old battery with a Hankook 59520 AGM battery, which is 95AH (old non AGM battery was 110AH, so seems like a downgrade to me, but not sure if a 95AM AGM is better than a 110AH standard battery).
This is the scale I am looking at (which states AGM).
Am I correct in thinking that if the battery was 100% charged (showing 13v) and I connected a 12v, 1amp load to it for 47.5 hours then at the end it would read 12.05v and have 50% capacity (i.e. 47.5AH) left? Are the scales accurate as I am seeing some odd figures from the battery if the scale is correct.
New battery with the new connectors in pic below just so you can see what it is, main question is about if I am interpreting the scale above correctly.
Clarifications re whether the scale in the first pic is accurate would be most welcome.
Thanks
Not exactly - those numbers are for no load conditions. So after 47.5 hours you need to disconnect the load and let the battery rest for several hours - the voltage will start climbing up and eventually stabilize at 12.05 Volts.
P
Phil_G
Guest
Those scales are theoretically accurate for a settled, open-circuit battery, but in practise are only a guide as many factors affect terminal voltage.
My suggestion would be to bulk charge the battery, allow it to CV float for a few hours, then do a controlled partial discharge
of say 30Ah, then see how the solar performs. As it stands right now, if the new battery was supplied 'charged' then the solar charger will only float, maybe after a very brief bulk charge. Bear in mind that although your solar charger says its in bulk charge mode, in this weather you're only getting a trickle so the terms 'bulk' and 'float' are more about the solar system attempting (and very possibly failing) to achieve or maintain those battery voltages.
This is why I said earlier that a decent solar shop should have a resistive floating power supply for testing controllers, around 18-20v at min 4Ω.
Cheers
Phil
My suggestion would be to bulk charge the battery, allow it to CV float for a few hours, then do a controlled partial discharge
of say 30Ah, then see how the solar performs. As it stands right now, if the new battery was supplied 'charged' then the solar charger will only float, maybe after a very brief bulk charge. Bear in mind that although your solar charger says its in bulk charge mode, in this weather you're only getting a trickle so the terms 'bulk' and 'float' are more about the solar system attempting (and very possibly failing) to achieve or maintain those battery voltages.
This is why I said earlier that a decent solar shop should have a resistive floating power supply for testing controllers, around 18-20v at min 4Ω.
Cheers
Phil
Just to demonstrate the effect of a load on battery voltage. The load was a tiny one 0.037 Amps - emulating T6 quiescent current 
. The battery had been resting for a week absolutely without load - after some use earlier so not fully charged - again emulating T6.
At time 0:00 hours the 37 mA load was connected for three hours and then disconnected. The voltage ramps up, and actually even overshoots the initial voltage for a few hours. On x-axis time in hours.
Then similar situation from a real T6 monitored using BM2 monitors. Main battery (92Ah) has constant load of 35 mA when the van is locked and resting over night - thus drained approx. 0.5 Ah by the van (37mA x 15 hours) The Aux battery has no load thanks to OEM split charge relay - only loaded with BM2 monitor - thus being approx. at the same charge state as the starter battery initially 15 hours ago.
. The battery had been resting for a week absolutely without load - after some use earlier so not fully charged - again emulating T6.At time 0:00 hours the 37 mA load was connected for three hours and then disconnected. The voltage ramps up, and actually even overshoots the initial voltage for a few hours. On x-axis time in hours.
Then similar situation from a real T6 monitored using BM2 monitors. Main battery (92Ah) has constant load of 35 mA when the van is locked and resting over night - thus drained approx. 0.5 Ah by the van (37mA x 15 hours) The Aux battery has no load thanks to OEM split charge relay - only loaded with BM2 monitor - thus being approx. at the same charge state as the starter battery initially 15 hours ago.
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