Solar new generation solar panels

[jazzeddie1234]

This will prevent to portable mat and roof mounted panels "fighting" each other

I noticed this happening between my 3 controllers so have staggered the voltages (absorption for example) 14.4, 14.3 , 14.2. This way the controllers drop out of the race in a more orderly fashion and the highest set one gets the job of maintaining float.

 

[Boots in Action]

I noticed this happening between my 3 controllers so have staggered the voltages (absorption for example) 14.4, 14.3 , 14.2. This way the controllers drop out of the race in a more orderly fashion and the highest set one gets the job of maintaining float.

@jazzeddie1234 , I can agree with you on the fact that theoretically each solar controller would (should) reduce its current output (amps) when the max absorption voltage setting for EACH has been achieved for the required period, before then dropping back to the float voltage set (once again for EACH controller) with minimal current applied intermittently to maintain a fully charged condition. However, my understanding is that it is not the LAST controller operating to the higher absorption voltage that determines which controller will continue the FLOAT stage, but the controller which has the highest float voltage setting, even if it has a lower max absorption voltage. This also does not take into account ambient and unit operating temperatures either. Perhaps you can enlighten me further on this matter?

 

[Macca_75]

@jazzeddie1234 , I can agree with you on the fact that theoretically each solar controller would (should) reduce its current output (amps) when the max absorption voltage setting for EACH has been achieved for the required period, before then dropping back to the float voltage set (once again for EACH controller) with minimal current applied intermittently to maintain a fully charged condition. However, my understanding is that it is not the LAST controller operating to the higher absorption voltage that determines which controller will continue the FLOAT stage, but the controller which has the highest float voltage setting, even if it has a lower max absorption voltage. This also does not take into account ambient and unit operating temperatures either. Perhaps you can enlighten me further on this matter?

I am not sure it would work. To "push" amps into a battery you need to be at a higher potential voltage than the battery - lets say 0.5v higher. So you would need a bigger difference than 0.1v

eg. regulator one will put out say 13.0v to charge a battery that has 12.5v (so bulk). The second regulator would "sense" 13.0v and would likely switch to absorption, outputting say 13.5v. Now the third regulator senses 13.5v and outputs a float of 14.0v. You end up with 1 regulator @ float, even though you likely still want either bulk or absorption from all 3 as the other 2 now sense the 14.0v float and either go into float or shutdown. (a pretty simplistic view of how it works in my head)

Mu understanding of Victron Battery sense is it determines the actual voltage at the battery, sends it to individual regulators. They subtract the 0.5v, calculate the actual battery voltage and act accordingly.

 

[poor but proud]

do you need mobile phone coverage to acess victron smart solar mppt app screens ? and when unplugged do you have to reset custom fields or does it revert to home settings on start up?

 

[Macca_75]

do you need mobile phone coverage to acess victron smart solar mppt app screens ? and when unplugged do you have to reset custom fields or does it revert to home settings on start up?

No - bluetooth to the local device only. You will need the internet occasionally as the app updates the firmware but if it doesn't have it the update waits until next time.

The settings are saved and don't need to be put in each time.

Victron = Rolls Royce of 12v stuff (but you pay accordingly).

 

[Boots in Action]

I am not sure it would work. To "push" amps into a battery you need to be at a higher potential voltage than the battery - lets say 0.5v higher. So you would need a bigger difference than 0.1v

eg. regulator one will put out say 13.0v to charge a battery that has 12.5v (so bulk). The second regulator would "sense" 13.0v and would likely switch to absorption, outputting say 13.5v. Now the third regulator senses 13.5v and outputs a float of 14.0v. You end up with 1 regulator @ float, even though you likely still want either bulk or absorption from all 3 as the other 2 now sense the 14.0v float and either go into float or shutdown. (a pretty simplistic view of how it works in my head)

Mu understanding of Victron Battery sense is it determines the actual voltage at the battery, sends it to individual regulators. They subtract the 0.5v, calculate the actual battery voltage and act accordingly.

Yes @Macca_75 , I agree. It would cause all sorts of problems. Generally speaking, bulk charging voltage is the same as absorption voltage. The only difference being during bulk charging, amps output into battery increases to max of charger capacity until set charging voltage is attained. Then absorption starts with the SAME high voltage but DECREASING current until max saturation is sensed. The next stage is FLOAT where voltage is reduced and a small current (usually less than 1 amp) is pulsed into battery to cover losses and to maintain "fully charged" condition. Incidentally, I am not aware of any battery that would require a 14.0 volt float voltage ( much too high causing too much heat and corroding the positive terminals on the plates). Usual float for 12 volt batteries is somewhere between 13.4 and 13.8 volts for cycle use, whilst storage voltage can be as low as 13.2 volts. As controllers are voltage controlled, there is no way a solar controller would drop into float stage at 14.0 volts or higher. It would be either still be in bulk or absorption.
If the Vitron Battery Sense does actually do what you say and INDIVIDUALLY adjusts EACH regulator connected to the same battery, that would be the only way to overcome the problem of multiple controllers.

 

[jazzeddie1234]

the controller which has the highest float voltage setting

Yes correct. I should have used float as a better example. Another example then (and depends on your preferred max voltages). BTW My controllers dont have a preset float current so will vary amps to maintain set volts.

So,
Controller 1 - 14.4 Absorption , 13.5 Float
Controller 2 - 14.3 Absorption , 13.4 Float
Controller 3 - 14.2 Absorption , 13.3 Float

As voltage reaches 14.2 the controller #3 drops to float, the #2 then #1 (however float for #2 and #3 is zero amps because #1 is still holding the voltage up at 14.4). When #1 gets to 14.4 it drops to 13.5 and tries to hold it there. #2/3 still do nothing until float voltage drops below their setting at which point they start to supply current. This ensures an orderly contribution to float where each controller knows when to drop out.

I only do this because my controllers are a little slow to react and jump around if 2 are trying to float the same voltage

 

[poor but proud]

i am beginning to think that my not so technical mind should stick with KISS .one panel one controller one battery, two panels two controllers two batteries,all of this technical stuff gives my mind and confidence a real hit ,apart from that how much extra power do you get (or need) for the $$$$ spent??

 

[jazzeddie1234]

stick with KISS

Unfortunately I've never been accused of keeping things simple

 

[Drover]

My system is set and forget, it does its job so I can enjoy my holiday, look at screen on unit or remote, it can have Bluetooth fitted but couldn't see any need, if it needs watching it's not doing its job.

 

[Crusty181]

@poor but proud - here is what I did in a nutshell

Bought one of these (as they were the cheapest at the time). I have the 200W model with the PWM controller

View attachment 66617

I made new Anderson leads but you could unscrew them from here and re-use them in a few steps from now.

Throw away this bit (keep the leads if you need them)

View attachment 66615

Buy one of these

View attachment 66616

* Make sure you get the SmartSolar model has it has Bluetooth built in. The BlueSolar model does NOT
** The 75 denotes 75v input from the panel (more than enough for 1 solar mat) - the number after the / is the number of Amps it can output. I would suggest the 75/15 as the 75/10 will be running flat out on a 200w blanket)

Attach the Anderson leads you either kept or made new to the Victron controller.

Connect the unit, follow instructions in the manual and open the app on your phone.

Configure the controller to match your batteries values (also don't forget to set the type of battery in there)

View attachment 66618

And thats it.

When you want to get more fancy, buy another Victron MPPT controller (I went the 100/20 so I could hook more panels up) and replace the unit in the van.

Throw away this

View attachment 66619

And replace it with the new Victron MPPT regulator. Setup the specs to match the battery again.

Grab one of these and attach it to the battery

View attachment 66620

Get the slightly more expensive blue model - it has better Bluetooth range than the black one and will reach your solar mat no matter where you lay it in the sun.

Then follow the manual and configure the battery sense and MPPT regulators into a network - see

This will prevent to portable mat and roof mounted panels "fighting" each other.

they come with the Kings variety MPPT controller at the moment

 

[mfexpanda]

My system is set and forget, it does its job so I can enjoy my holiday, look at screen on unit or remote, it can have Bluetooth fitted but couldn't see any need, if it needs watching it's not doing its job.

mine too @Drover 560w 5 panels 2 x 120amp AGM .
started adding up $ going to 200amp lithium . would need to change the solar regulator as well and then work out how to mains charge them as the setek doesn't do lithium . got a head ache and gave up

 

[Drover]

they come with the Kings variety MPPT controller at the moment

I think most of the panels you buy anywhere as a bundle the controllers should be binned and replaced with a decent one, well I wouldn't bin them as they are good for using for a shed battery charger for the ride on or boat batteries.

 

[Crusty181]

mine too @Drover 560w 5 panels 2 x 120amp AGM .
started adding up $ going to 200amp lithium . would need to change the solar regulator as well and then work out how to mains charge them as the setek doesn't do lithium . got a head ache and gave up

Im have much the same as you 600w on the roof, 2 x 130ah agm. I generate more power than I use even in overcast, makes no sense to throw it out and swap a kidney for even more power that I won't use. To save 30kg from the 3200kg Im towing makes no sense either; the vans 30kg lighter after 2 x showers for free

By the time lithium is a thing for me, Im guessing Ill be able to get a 10 pack at Bunnings for $9.99

 

[Macca_75]

i am beginning to think that my not so technical mind should stick with KISS .one panel one controller one battery, two panels two controllers two batteries,all of this technical stuff gives my mind and confidence a real hit ,apart from that how much extra power do you get (or need) for the $$$$ spent??

Seriously not that hard. Take time to read it, ask questions, understand it. You'll have the basics for life and it might come in handy when cmaped up one day and something goes wrong.

 

[Macca_75]

they come with the Kings variety MPPT controller at the moment

Not sure how good or bad the Kings MPPT are - never seen, heard or tried to search any feedback on them.

 

[jazzeddie1234]

started adding up $ going to 200amp lithium

I'm half way through a 200ah lithium upgrade so will post my changes and costs when finished. My biggest headache is the simplicity I lost with one chemistry type in the ute and van (ute tray battery was simply paralleled with the van batteries most of the time) now requires a second dc-dc. And I have to increase the mains charging capacity because it will take forever to recharge 200ah at 10ish amps from the setec

 

[Drover]

While I only have AGMs, mine are kept charged from the panels, I rarely use my 240v charger, if you park it in a shed then I would just throw a small panel on shed roof and plug it into van, that's how my boat and ute stay charged when I'm away for months.....I couldn't see any value in replacing the Setek actually, it would be a pain in the bum to do............If a 240v charger is needed just get a multi stage portable charger that will do your van and utes batteries........ The only thing lithium have that's of advantage to me at present is weight.... Even though we camp for 4 months or so a year, my set up works and cost less than one lithium... Gladly accept a couple for testing though, the Epever is lithium friendly.

 

[Macca_75]

Yes @Macca_75 , I agree. It would cause all sorts of problems. Generally speaking, bulk charging voltage is the same as absorption voltage. The only difference being during bulk charging, amps output into battery increases to max of charger capacity until set charging voltage is attained. Then absorption starts with the SAME high voltage but DECREASING current until max saturation is sensed. The next stage is FLOAT where voltage is reduced and a small current (usually less than 1 amp) is pulsed into battery to cover losses and to maintain "fully charged" condition. Incidentally, I am not aware of any battery that would require a 14.0 volt float voltage ( much too high causing too much heat and corroding the positive terminals on the plates). Usual float for 12 volt batteries is somewhere between 13.4 and 13.8 volts for cycle use, whilst storage voltage can be as low as 13.2 volts. As controllers are voltage controlled, there is no way a solar controller would drop into float stage at 14.0 volts or higher. It would be either still be in bulk or absorption.
If the Vitron Battery Sense does actually do what you say and INDIVIDUALLY adjusts EACH regulator connected to the same battery, that would be the only way to overcome the problem of multiple controllers.

Sorry @Boots in Action - I was just using nice round numbers and not what I actually have set (as each battery may be slightly different). But yeap - agree 100%

 

[Macca_75]

I'm half way through a 200ah lithium upgrade so will post my changes and costs when finished. My biggest headache is the simplicity I lost with one chemistry type in the ute and van (ute tray battery was simply paralleled with the van batteries most of the time) now requires a second dc-dc. And I have to increase the mains charging capacity because it will take forever to recharge 200ah at 10ish amps from the setec

I picked up one of these 2nd hand (like new) as they guy was upgrading to a larger unit (price I paid I feel like I stole it).

Want to stuff the (new when the kids stop coming with us) van with Lithium and Solar so we can run the aircon with no generator.