Thread Rating:
  • 0 Vote(s) - 0 Average
  • 1
  • 2
  • 3
  • 4
  • 5
Outback charge controller not using all of the arrays volts
#11
Can you please advise the NOCT Vmp & Imp values for your panels.
Or tell us the brand & model of the panels please.
You mentioned you're in Tennessee, daytime temps are ~27degC atm? Ie panels will be hotter than NOCT = LESS output & lower Vmp numbers.
Running off solar, DIY & electronics fan :-)
#12
.. 6 longi solar panels and 6 Canadian panel all with the same specs.. this issue isn’t related to the temp outside... I get very close to the same amount of watts all year
#13
Have you tried a different config? A 2S instead of 3S? You are still within the spec of your batteries. Assuming regular 4.2 * 14S = 58.8v. Vmp is 33V * 2 = 66V. Your MPPT controller is more efficient closer to your battery voltage. You might lose 5% efficiency going with 3S. Also efficiency also drops when you max out your MPPT contro. Probably another couple % drops. You need to look at the efficiency curve of your controller.

I did that once to test and found it was slightly better but it means thicker cable runs so I decided for more panels than more efficiency.
#14
2s is how I had it wired when I wasn’t using a 16s battery because my grid tie inverters voltage sweat spot was roughly 66v.
I had to go to 3s because 2s was not high enough above the battery voltage to charge batteries properly in the winter when it’s very hot., my battery voltage is 58v-65.6v. I’m actually only charging to 65.1 but that’s kinda irrelevant


Finally found something regarding what I was trying to say, I didn’t know how to put it in the correct words.

This is saying without hyper voc that the 150v max includes the battery voltage,, so 66v battery minus 150v is 84v that the controller can use from my array.. problem is that my array is 100vmp,, controller isn’t using roughly 16v that it could be using to convert to more amps..,, right around 78v-86v (depending on battery voltage) is the max constant voltage I see from my array when the controller acts like it’s getting all the power my panels can deliver(its not tho)... I’m getting 3200w max constant from array but if the controller could use that other 16v then I would be getting real close to the max (3660) my panels are trying to give me.
This explains why as my battery voltage rises the controller uses less volts from the array,, and the other way around,,, as battery voltage falls the controller uses more volts from array.. the controller won’t allow no more than roughly 150v array + battery

This is a hard lesson learned for me,, the string sizing tools told me 2s wouldn’t work well (I agreed) but it didn’t tell me that wiring my panels at 3s would keep me from getting max power (all of the volts) from my array Sad
Now wishing I would have got the midnite 150 instead of outback 150.. but I’m still wondering how many amps either controller can raise from the panels input amps to charge battery.. I’m thinking it’s around 20amps that the controller can raise the input arrays amps. this amount would also be the amount of volts higher than battery voltage that can be ACTUALLY used at peak production.,,this means my array should be only roughly 86v to get max power from my panels when they are capable of giving me max power

Now knowing all of this I should have installed an array around 90vmp max to get very close to all the power from panels at peak harvest
#15
(06-02-2020, 01:33 AM)Doin it Wrote: 2s is how I had it wired when I wasn’t using a 16s battery because my grid tie inverters voltage sweat spot was roughly 66v.
I had to go to 3s because 2s was not high enough above the battery voltage to charge batteries properly in the winter when it’s very hot., my battery voltage is 58v-65.6v


Finally found something regarding what I was trying to say, I didn’t know how to put it in the correct words.

This is saying without hyper voc that the 150v max includes the battery voltage,, so 66v battery minus 150v is 84v that the controller can use from my array.. problem is that my array is 100vmp,, controller isn’t using roughly 16v that it could be using to convert to more amps..,, right around 78v-86v (depending on battery voltage) is the max constant voltage I see from my array when the controller acts like it’s getting all the power my panels can deliver(its not tho)... I’m getting 3200w max constant from array but if the controller could use that other 16v then I would be getting real close to the max (3660) my panels are trying to give me.
This explains why as my battery voltage rises the controller uses less volts from the array,, and the other way around,,, as battery voltage falls the controller uses more volts from array.. the controller won’t allow no more than 150v array + battery

This is a hard lesson learned for me,, the string sizing tools told me 2s wouldn’t work well (I agreed) but it didn’t tell me that wiring my panels at 3s would keep me from getting max power (all of the volts) from my array Sad
Now wishing I would have got the midnite 150 instead of outback 150.. but I’m still wondering how many amps either controller can raise from the panels input amps to charge battery.. I’m thinking it’s around 20amps that the controller can raise the input arrays amps. this amount would also be the amount of volts higher than battery voltage that can be ACTUALLY used at peak production.,,this means my array should be only roughly 86v to get max power from my panels when they are capable of giving me max power

Now knowing all of this I should have installed an array around 90vmp max to get very close to all the power from panels at peak harvest
The article you list says:
  >"When the Classic input voltage rises above 150v it will switch off (stop outputting power)...."
e.g. it will go into HyperVOC mode 
  >"...it will switch off (stop outputting power)......
e.g. power will go to 0 (0 volts, 0 amps on input and output)
  >"... in HyperVOC mode the microprocessor and all other functions like AUX will continue...."
e.g. it will continue to operate rather than do a hard shutdown - except that power = 0.    This is allows external controls (AUX1 and AUX2) and data logging and internet access to continue to work during this condition.  And when the condition passes, the MPPT will resume making power without having to manually reboot the system. 

>This is saying without hyper voc that the 150v max includes the battery voltage,, so 66v battery minus 150v is 84v that the controller can use from my array.....
Its not saying this. 

Its saying that Midnite Classics have protection against extreme weather conditions such as sever cold (as in 30 below 0 type of thing).  They call this condition/feature "HyperVOC" - e.g. extreme cold can cause voltages to spike temporarily.  For example, in the early sun of a cold night it might still be 30 below 0 cause 'extra high' voltages until the sum warms things up.   So rather than shut the controller down (causing you to manually turn it back on) the HyperVOC feature kicks in and let's the internal processor will continue to operate so that it can resume making power when the extreme condition goes away...  such as maybe later in the morning when the temp goes from 30 below 0 back to 0.  

This has nothing to do with 85'ish volts - MPPT - that you are seeing.
#16
3s is most likely more efficient than 2s for this controller. Most are to be honest. Being close to battery voltage is for old pwm controllers and badly designed mppt. Most buck/bost converters today have a set voltage range where they are ALOT more efficient and most of the 150ish volt is around 100-110 if im not mistaken. I have read some paper about this back in the days

So if we are going to explain why you get 85V.. Thats tricky. Because generally with perfect conditions the sweet spot is around Vmp. with that said the controller will regulte the voltage to the spot where it gets the most Power out of it. If thats 85 that may be it for this controller vs the panels. Its hard to tell without putting in another type of controller comparing wattage. NOTE that you need an external device to meassure wattage since some of the controller doesnt even have a shunt inside and interpolates the output......
The Ultimate DIY Solar and build place
YouTube / Forum system setup / My webpage  Diy Tech & Repairs

Current: 10kW Mpp Hybrid | 4kW PIP4048 | 2x PCM60x | 100kWh LiFePo4 | 20kWh 14s 18650 |  66*260W Poly | ABB S3 and S5 Trip breakers
Upcoming: 14S 18650~30kWh
#17
The Hyper Voc bit in the manual is about overload not normal operation & is irrelevant anyway.

OK, thanks for posting the panel details.
So I found data for the LR6-60PE-305M panels here:
http://www.en.longi-solar.com/uploads/at...9aba93.pdf
The "Electrical Characteristics at NOCT" values are:
Vmp = 30.3V x 3 for your system = 90.9V at NOCT mp, less say 1V cable losses = 89.9V at the controller
Imp = 7.39A x 4 strings (of 3 in series, 12 panels right?) = 29.56A at NOCT mp
Now you need to add temperature compensation for the actual temp the cells are at (yes it's definitely relevant sorry!)
See the graph in the linked data sheet bottom left? It shows what happens with cell temp. Hotter = lower voltage = exactly what you're seeing.
Which is very close to what the FM60 is displaying.
So your controller is doing it nearly perfectly according to the NOCT & temp specs.
None of us gets the STC spec power! Wish we did but that's the way the silicon works ;-)
Running off solar, DIY & electronics fan :-)
#18
It says hyper voc gives u the option to go up to (PANEL VOLTAGE) the max operating voltage (150v) PLUS the battery voltage. So essentially array can be 150v plus battery voltage only while using hyper voc... without hyper voc there is no battery voltage plus 150v array,, there is only 150v array +battery combined....
I know that regardless the controller will not mppt the array higher than 86v using hyper voc or not so. Wouldn’t get more power, but reason for showing this pic is to confirm that the controller won’t allow more volts input from array than what’s left from 150v once battery is subtracted from 150, which in my case is roughly 86v..
that sentence is saying without hyper voc (which my outback doesn’t have) u do not have the option to go up to max operating voltage because u have to minus the battery voltage from the max the controller can accept...


U can still use arrays up to 150v and controller will still function but it will mppt the voltage down to whatever is left from 150v once battery voltage is subtracted from 150v..

Anybody else reading it that way?
#19
(06-02-2020, 02:13 PM)Doin it Wrote: It says hyper voc gives u the option to go up to (PANEL VOLTAGE) the max operating voltage (150v) PLUS the battery voltage. So essentially array can be 150v plus battery voltage only while using hyper voc.....
that sentence is saying without hyper voc (which my outback doesn’t have) u do not have the option to go up to max operating voltage because u have to minus the battery voltage from the max the controller can accept...


U can still use arrays up to 150v and controller will still function but it will mppt the voltage down to whatever is left from 150v once battery voltage is subtracted from 150v..

Anybody else reading it that way?

Re the "hyper voc" if you go over the 150V if shuts off. It's an "over-voltage protection" feature. It doesn't help or get you more power.
Most MPPT's will only work if Vin is > Vbattery & that's what your FM60 does too.
Be happy it's working well ! :-)
Running off solar, DIY & electronics fan :-)
#20
I’m not saying hyper voc helps get more power..
Red I appreciate your research I understand getting 100 or 250w less due to certain conditions,, but I’m saying there’s no way I should be getting only roughly 3100w out of a 3660w array.. I believe this is happening due to the 150v charge controllers only being able to raise the charge amps by a certain amount and therefor will not accept all of the Volts from array, it will only mppt-accept voltage above battery voltage that is the same as the amount of amps it can create.. this is why 150v combined (battery+array) is all the controller can actually use..
Ofcourse the controller can use higher voltages from array when it’s not trying to get max power out of the panels, like my second charge controller pic shows


Forum Jump:


Users browsing this thread: 2 Guest(s)