Jump to content

Axpert 5kva


Alec Swanepoel
 Share

Recommended Posts

Welcome Alex.

Cannot use Volts for SOC.

You should invest in a Victron BMV702 - 702 not 700 - for you will start, if you stay with this forum, wanting to measure your batteries midpoint values also. :D

Link to comment
Share on other sites

There are a multitude of software packages being written on this forum for Voltronic devices.

AICC and SolarMon the first two with SolarMon still being developed and expanded, with a few new ones coming along quite nicely.

See here: http://powerforum.co.za/forum/73-the-internet-of-things/

Idea is to use one of these systems to manage your Voltronic device better, with the batteries being monitored properly, using a BMV, as part of your system.

@Camel has had some good prices on BMV's and their cables.

With @Energy busy setting up a forum store for better prices soon also.

Link to comment
Share on other sites

Up until a moment before you start measuring your inverter is in line mode and your charging rate is 10A. From the voltage it appears you are in bulk or absorb and your batteries are not fully charged. When you Axpert goes into float (i.e. the batteries are 99% charged) the middle LED does not flash but is on permanently. If it is charging and is in bulk or absorb the LED flashes. Good batteries will still steadily accept 1% of charge when they are full.

You then switch to battery and immediately your voltage drops from 56.8V to 51.7V  2 minutes later. This is purely because you are no longer charging the batteries. 10 minutes later your batteries are at 50.1V which is closer to your batteries true voltage and a little while later you kick back to grid. I suspect your settings for program 12 & 13 are too close together. 

MY grid power has just gone off and in 4 minutes my batteries have dropped from 54.4V to 51.1V with a 12A draw - entirely normal.

I am away tomorrow but post a screenshot of your settings and the Axpert mechanics will sort it out I am sure.

Addition: Now ½ hour later the battery voltage has recovered to 51.4V with a draw of 5A.

Edited by Chris Hobson
Addition
Link to comment
Share on other sites

If you do what Chris recommend you will be set for good. He is an expert with the solar goodies

Sent from my SM-G920F using Tapatalk

Link to comment
Share on other sites

15 hours ago, The Terrible Triplett said:

There are a multitude of software packages being written on this forum for Voltronic devices.

AICC and SolarMon the first two with SolarMon still being developed and expanded, with a few new ones coming along quite nicely.

See here: http://powerforum.co.za/forum/73-the-internet-of-things/

Idea is to use one of these systems to manage your Voltronic device better, with the batteries being monitored properly, using a BMV, as part of your system.

@Camel has had some good prices on BMV's and their cables.

With @Energy busy setting up a forum store for better prices soon also.

Very soon!

Link to comment
Share on other sites

Unbelievable response. Thanks!!!

Played around with the battery settings - Chris, thanks, you put me on the right track - system already performing a lot better. Would like to know what software route to go?????  - must say I like Jaco's setup. Any contact numbers?

Best place to buy a BMV 702 ??

Settings attached.

Thanks!!!!

 

IMG-20160524-WA0003.jpg

Link to comment
Share on other sites

Hi Alec

You can safely raise your max charge rate to 20A (and your AC charge rate to 20A if you want to). 20A on a 200Ah battery bank is still a C/10 charge rate.

Chris

 

Addition: The max you'll ever see from your current panels is just below 15A so there is no cause for concern in terms of over charging from solar. It just means that if you batteries are not fully charged you can use every Watt of energy available from you panels. And at 20A AC charging you will reach fully charged sooner. 

Link to comment
Share on other sites

On 23/05/2016 at 10:38 PM, Manie said:

If you do what Chris recommend you will be set for good. He is an expert with the solar goodies

Sent from my SM-G920F using Tapatalk

Thanks for the vote of confidence Manie.

I doubt I am an expert. I know one particular setup (Axperts) well and folk like Mike and Silver who are installers have a much broader experience.

 

Link to comment
Share on other sites

On 5/23/2016 at 8:15 PM, Alec Swanepoel said:

5kva Axpert, 3 x 250w 24 V Yingli panels in series. 2 x Parrallel packs of 4 x 102ah Osaka batteries in series. 

I have a question:
Presuming the 3 panels in series ( 29.5v per panel), so 88.5v @ 750w max 8.14amps per panel on a good day, for losses must also be accounted for, is that enough to charge the 48v 204ah bank?

For as Chris also said, min charge should be 20amps, yet the panels, as per Chris, can do max +-15amps, for on average 5.5 hours per day (being the annual average of good sunshine) which becomes worse if loads are powered at the same time, then batteries are definitely not getting enough amps to charge properly.

5% charge rate is for weekend only use, has the whole 5 days to recharge.
10% charge rate is for general daily use.
13% charge rate is best for off-grid with loads.
You have to get the batteries fully charged every day if they are used every night, so min 10%, max 13%.

 

Alec, another thought to ponder on: When the batts need replacement one day, get max 4 batteries with the AH rating you need.

Link to comment
Share on other sites

3 hours ago, Chris Hobson said:

Thanks for the vote of confidence Manie.

I doubt I am an expert. I know one particular setup (Axperts) well and folk like Mike and Silver who are installers have a much broader experience.

Yes Mike and Silver are, I know for a fact on the Axpert and BMV you are !!!

Link to comment
Share on other sites

Hope someone can help. ..

5kva Axpert, 3 x 250w 24 V Yingli panels in series. 2 x Parrallel packs of 4 x 102ah Osaka batteries in series. 

If you study the data pic - from 56.8V to 50V in 17 minutes with a 5 - 6 amp load

Batteries 2 months old 

IMG-20160523-WA0009.jpg

Hi Manie,

I also installed a Axpert 5kva, and started with 3 panels.

I found it was enough to charge the batteries, with very light usage and good weather in summer. But more than that i think one is abusing the batteries, by cycling them? Also passing clouds will have a more of pronounced effect.

So I put in a 2nd string and found that I could better carry our daytime load in summer, but could still not run the aircon during the day from solar, and the Ironing would eventually force the inverter to switch to Eskom even in good weather.

So we added a 3rd string and it works really well. No real issues now.

Although we are going into winter :) and I have adjusted the panels to winter sun. But am now thinking that if I add the 4th string of panels, I will maximize the early morning and late afternoon power generation ability.

Also I will be able to run the aircon for heating in winter earlier rather than from 10am-2pm? Maybe from 9-3pm?

Expect to add the 4th string soon :)

And at night the batteries are fully charged from Eskom in my case.

Our load varies from around 350 watts at the lowest to 800w during the day, once the ironing starts it spikes to around 2.2kw for short periods and if the aircon runs it sits at around 2kw continuously while running everything.

Enjoy the solar journey :)

Link to comment
Share on other sites

24 minutes ago, Chris Hobson said:

With this solar thing you are never really finished.

Jip ... the secret, and here each are on their own, is to get to: There, it is done. 

If we don't get there we will keep on tinkering, changing, adjusting and adding, which in the end may negate all savings, more so if one loses focus on the costs incurred to date.

Where that line is ... go and enjoy finding it. :D

Link to comment
Share on other sites

I am contemplating a 5th string to give me 3000W or close to 3000W for a larger part of the day. With this solar thing you are never really finished.

 

Hi Chris,

Just on the 5th string.

I understand that the Axpert Mppt cannot handle more than 115volts / 3000watts from the panels? Or did I miss something?

As I understand it one has to add a second parallel Axpert with more panels to get more

Input or at least a separate Mppt controller with its

Own strings?

By the way i am running 9 X 250watt polycrystalline panels, theoretically 2250watts in total, and have found the Axpert software seems to show show us making around 16% more than this sometimes when under load? Which seems to be even better than what I ever expected :)

Warren

Link to comment
Share on other sites

Hi Warren 

I have 12 x 250W panels and max produced 3300W on cool day with some cloud. I was led to believe that so long as you did not exceed the max voltage of the MPPT you were safe. The inverter draws the power it needs. So if the panels are producing more than +- 3000W then the inverter limits itself to that. The advantage of more than 3000W of panels can be demonstrated by the following scenario. Say it is a cloudy day and you can only produce 2000W  from 3000W of panels. If you had 3750W of panels you could now produce 2500W. If the sun was shining brightly you would still be limited to +-3000W. That is how it was explained to me. When I wanted to install an Imeon the initial proposed install had 18 x 250W panels i.e. 4500W of PV for a 3kW inverter. This makes sense  as the inverter draws the current from the panels rather than the panels "pushing" the current into the inverter. I will confirm that what I want to do is possible before I launch into the unknown.

Mike SuperDIY and others do any of you have practical experience in this matter?

 

Link to comment
Share on other sites

Hi Warren 

I have 12 x 250W panels and max produced 3300W on cool day with some cloud. I was led to believe that so long as you did not exceed the max voltage of the MPPT you were safe. The inverter draws the power it needs. So if the panels are producing more than +- 3000W then the inverter limits itself to that. The advantage of more than 3000W of panels can be demonstrated by the following scenario. Say it is a cloudy day and you can only produce 2000W  from 3000W of panels. If you had 3750W of panels you could now produce 2500W. If the sun was shining brightly you would still be limited to +-3000W. That is how it was explained to me. When I wanted to install an Imeon the initial proposed install had 18 x 250W panels i.e. 4500W of PV for a 3kW inverter. This makes sense  as the inverter draws the current from the panels rather than the panels "pushing" the current into the inverter. I will confirm that what I want to do is possible before I launch into the unknown.

Mike SuperDIY and others do any of you have practical experience in this matter?

 

Yes Chris i also did read it somewhere. Never tested it.

Sent from my SM-G920F using Tapatalk

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

 Share

×
×
  • Create New...