Programming Victron Solar Chargers.

[Sandy]

Over the summer I installed 200 Watts of solar panel that are connected to a Victron MTTP 75/15 to do all the wiggly amps stuff.

On a damp cold December afternoon I've been looking at YouTube trying to find out if the default settings for a 'high battery' could be improved and lost the will to live. It is quite apparent that lots of people don't know they don't have a clue what they are talking about. There is one YouTube video from Victron that is a talking head with English as a second language who chatters on with stuff and might make sense after looking at it about 20 times when once was enough to turn anybody off using their product. Perhaps not the type of video for a geeky engineer like me to present.

Can anybody point me at some documentation that tells me how to compute the State of Charge and what is the best charging profile depending on voltage?

 

[sarabande]

Facebook groups.

1 "Victron Energy". It sometimes contains real nuts living offgrid in old nuclear rocket sites, but amongst the dross are numerous really chatty experts who can draw simple diagrams


2 "12v Boating Group". Also contains nuts living on 40ft containers sealed with duct tape and floating on the Thames. Some real enthusiasts who can recite Peukert backwards. And sideways.

Just remembered, my ex-next door neighbour is the chap who edits the instruction booklets. I think he uses a microscope...

 

[Sandy]

Facebook groups.

1 "Victron Energy". It sometimes contains real nuts living offgrid in old nuclear rocket sites, but amongst the dross are numerous really chatty experts who can draw simple diagrams


2 "12v Boating Group". Also contains nuts living on 40ft containers sealed with duct tape and floating on the Thames. Some real enthusiasts who can recite Peukert backwards. And sideways.

Just remembered, my ex-next door neighbour is the chap who edits the instruction booklets. I think he uses a microscope...

Thanks @sarabande. We must meet up and test the new coffee pot once I finish helping Santa out.

 

[Aja]

Over the summer I installed 200 Watts of solar panel that are connected to a Victron MTTP 75/15 to do all the wiggly amps stuff.

On a damp cold December afternoon I've been looking at YouTube trying to find out if the default settings for a 'high battery' could be improved and lost the will to live. It is quite apparent that lots of people don't know they don't have a clue what they are talking about. There is one YouTube video from Victron that is a talking head with English as a second language who chatters on with stuff and might make sense after looking at it about 20 times when once was enough to turn anybody off using their product. Perhaps not the type of video for a geeky engineer like me to present.

Can anybody point me at some documentation that tells me how to compute the State of Charge and what is the best charging profile depending on voltage?

I had exactly the same issues as you. I posted on here my set up and @PaulRainbow came back fairly quickly and told me what to do with the Bluetooth set up procedures. Has worked flawlessly for the past 2 years. Great bit of kit.

 

[Buck Turgidson]

Just open the app. As for what voltages to set that is best coming from your battery manufacturer. I have documentation from odyssey for my house battery and use their recommendations.

 

[geem]

Over the summer I installed 200 Watts of solar panel that are connected to a Victron MTTP 75/15 to do all the wiggly amps stuff.

On a damp cold December afternoon I've been looking at YouTube trying to find out if the default settings for a 'high battery' could be improved and lost the will to live. It is quite apparent that lots of people don't know they don't have a clue what they are talking about. There is one YouTube video from Victron that is a talking head with English as a second language who chatters on with stuff and might make sense after looking at it about 20 times when once was enough to turn anybody off using their product. Perhaps not the type of video for a geeky engineer like me to present.

Can anybody point me at some documentation that tells me how to compute the State of Charge and what is the best charging profile depending on voltage?

You can't compute the state of charge from an MPPT. It's a charge controller not a shunt.
What batteries do you have? The charge profile should be to suit your batteries, based off manufacturers information

 

[KompetentKrew]

I hate Facebook groups for technical discussion - they've improved threading slightly in the last year or two (previously it didn't properly nest replies after the second level), but it has always felt like they're trying to foster engagement rather than be informative. E.g. only the most popular / contentious replies are shown by default, so everybody leaps in to have their say; the correct answer may already have been given, but it's hidden and not shown prominently even after you show all replies.

Facebook has fostered a culture in which everybody gets to post whatever they like, irrespective of whether it's interesting or helpful to people. The 12vBoating group can be great, but I don't know how the regulars on there keep their sanity because there are so many questions from canal boaters about running their batteries down to 11v and can they run kettles and electric heaters off them. That group needs a GCSE physics FAQ.

For Victron stuff, the official Victron Community forums can be quite good.

 

[Sandy]

I hate Facebook groups for technical discussion - they've improved threading slightly in the last year or two (previously it didn't properly nest replies after the second level), but it has always felt like they're trying to foster engagement rather than be informative. E.g. only the most popular / contentious replies are shown by default, so everybody leaps in to have their say; the correct answer may already have been given, but it's hidden and not shown prominently even after you show all replies.

Facebook has fostered a culture in which everybody gets to post whatever they like, irrespective of whether it's interesting or helpful to people. The 12vBoating group can be great, but I don't know how the regulars on there keep their sanity because there are so many questions from canal boaters about running their batteries down to 11v and can they run kettles and electric heaters off them. That group needs a GCSE physics FAQ.

For Victron stuff, the official Victron Community forums can be quite good.

I understand where you are coming from! I've taken a peek in there and quickly closed the door!

 

[GHA]

if you want your batteries to like you then unfortunately that means splashing out on a victron smartshunt as well, or the bmv whatever it's called, but needs bluetooth. Then the regulator speaks to the shunt and knows the SOC, current & voltage at the battery. Otherwise the regulator will switch to float too early if there's anything else turned on, it thinks it is charging the battery but half the power is actually going into a plotter or laptop or fridge or whatever. The voltage at the regulator will be different to the battery as well when it's charging so having the shunt data means it can pump up the voltage to allow for any voltage drop between the regulator and the battery. So many batteries are murdered with owners seeing the regulator switch to float - "look, my batts are charged before lunch!" but they're nowhere near charged cos the power went to other loads. Then look to the battery datasheet for charge/float voltages.

 

[geem]

if you want your batteries to like you then unfortunately that means splashing out on a victron smartshunt as well, or the bmv whatever it's called, but needs bluetooth. Then the regulator speaks to the shunt and knows the SOC, current & voltage at the battery. Otherwise the regulator will switch to float too early if there's anything else turned on, it thinks it is charging the battery but half the power is actually going into a plotter or laptop or fridge or whatever. The voltage at the regulator will be different to the battery as well when it's charging so having the shunt data means it can pump up the voltage to allow for any voltage drop between the regulator and the battery. So many batteries are murdered with owners seeing the regulator switch to float - "look, my batts are charged before lunch!" but they're nowhere near charged cos the power went to other loads. Then look to the battery datasheet for charge/float voltages.

It doesn't work like that. Yes, it's way better to accurate voltage for the MPPTs to charge to, so the smart shunt is great for that but you can achieve the same with a smart sense. This will bluetooth the actual battery voltage and temperature to the MPPT. The MPPT doesn't care if half the current is going into other devices rather than the batteries. It can only measure voltage. Same for a smart shunt. They will only stop charging at the set point voltage you select. Even if the smart shunt say the battery is 100% charged, the charge will keep happening until the batteries hit the voltage you have selected for them to go into absorption.

 

[GHA]

It doesn't work like that. Yes, it's way better to accurate voltage for the MPPTs to charge to, so the smart shunt is great for that but you can achieve the same with a smart sense. This will bluetooth the actual battery voltage and temperature to the MPPT. The MPPT doesn't care if half the current is going into other devices rather than the batteries. They will only stop charging at the set point voltage you select. Even if the smart shunt say the battery is 100% charged, the charge will keep happening until the batteries hit the voltage you have selected for them to go into absorption.

" It can only measure voltage. Same for a smart shunt." - that's actually incorrect, with the smartshunt the regulator knows the current as well & from that knows when best to end absorption & switch to float when the battery is actually fully charged based on the tail current as opposed to using adaptive absorption time which picks one of 4 options for absorption time based on battery voltage first thing in the morning, which will change depending on what loads are running.
Though smartsense & adaptive absorption time will still be streets ahead of nothing & cheaper, just not as good as using tail current into the battery.

 

[Sandy]

if you want your batteries to like you then unfortunately that means splashing out on a victron smartshunt as well, or the bmv whatever it's called, but needs bluetooth. Then the regulator speaks to the shunt and knows the SOC, current & voltage at the battery. Otherwise the regulator will switch to float too early if there's anything else turned on, it thinks it is charging the battery but half the power is actually going into a plotter or laptop or fridge or whatever. The voltage at the regulator will be different to the battery as well when it's charging so having the shunt data means it can pump up the voltage to allow for any voltage drop between the regulator and the battery. So many batteries are murdered with owners seeing the regulator switch to float - "look, my batts are charged before lunch!" but they're nowhere near charged cos the power went to other loads. Then look to the battery datasheet for charge/float voltages.

No worries my power system is all Victron. Shore power, SmartShunt, MTTP and even the battery voltage/temperature dooberry.

 

[GHA]

No worries my power system is all Victron. Shore power, SmartShunt, MTTP and even the battery voltage/temperature dooberry.

Your batteries will be pleased
Then it's try to find battery manufacturers recommended settings for absorption & float, trojan T105 ones look like this, absorption is a bit higher than most >

Then in the victron connect app settings those figures go in the options for absorption & float voltages, turn on expert mode & look in absorption n duration to check both adaptive absorption and tail current are turned on with tail current set to maybe between 1% & 2% of battery capacity.
Of course the smartshunt needs to have a ve smart network set up & the mptt connected to this network.

Think that's about it, quicker to do than to tell...

 

[geem]

Are

No worries my power system is all Victron. Shore power, SmartShunt, MTTP and even the battery voltage/temperature dooberry.

You connecting them all with the VE network?