Skip to content
View in the app

A better way to browse. Learn more.

Power Forum - Renewable Energy Discussion

A full-screen app on your home screen with push notifications, badges and more.

To install this app on iOS and iPadOS
  1. Tap the Share icon in Safari
  2. Scroll the menu and tap Add to Home Screen.
  3. Tap Add in the top-right corner.
To install this app on Android
  1. Tap the 3-dot menu (⋮) in the top-right corner of the browser.
  2. Tap Add to Home screen or Install app.
  3. Confirm by tapping Install.

Solar Installation Advice - Off grid, small house

Featured Replies

On ‎2017‎/‎01‎/‎17 at 5:21 AM, DeepBass9 said:

How long did your T1275s last? I have 8 of them that are getting towards 2 years old now, with no problems as yet.

Just wrote you a long reply but lost it somehow.  Short version, they were finished when I got them.  Only running 12V LED's at night and a 350W cheapy inverter when the sun shines

  • Replies 66
  • Views 16.2k
  • Created
  • Last Reply

Top Posters In This Topic

Most Popular Posts

  • Chris Hobson
    Chris Hobson

    I see you already have been made aware of the 3kVA Plus version which can handle 1500W of panels. I would not use Trojans with an Axpert. There are hassles with the Trojans high charge voltage and nee

  • I will trust in what the manufacturer of the batts say This is key, add balancers and look after the things and you will be fine. And if my gravity readings go out of spec, I will use the cha

  • SilverNodashi
    SilverNodashi

    I have found the OmniPowers to work quite well with Axpert inverters. Sacred Sun and Vision batteries also work quite well. 

Posted Images

On ‎2017‎/‎01‎/‎17 at 5:21 AM, DeepBass9 said:

How long did your T1275s last? I have 8 of them that are getting towards 2 years old now, with no problems as yet.

Just wrote you a long reply but lost it somehow.  Short version, they were finished when I got them.  Only running 12V LED's at night and a 350W cheapy inverter when the sun shines

On ‎2017‎/‎01‎/‎17 at 9:55 AM, SilverNodashi said:

I have found the OmniPowers to work quite well with Axpert inverters. Sacred Sun and Vision batteries also work quite well. 

Thanks

  • Author
7 hours ago, dax021 said:

Just wrote you a long reply but lost it somehow.  Short version, they were finished when I got them.  Only running 12V LED's at night and a 350W cheapy inverter when the sun shines

Thanks for the reply.

8 hours ago, dax021 said:

 Short version, they were finished when I got them.  

..... How long did you use them once they were finished? I was wondering how long one can use the batteries once they not accepting charge properly. Once you are at that stage you not worried about DOD so long they can power your system overnight. 

2 hours ago, Chris Hobson said:

I was wondering how long one can use the batteries once they not accepting charge properly.

You can use them as long as that piece of string is. :D

One can also go in overdrive and equalise the dinges out of them for a week or so. Maybe you get some more life out of them. But that is not a given at all.

2 hours ago, Chris Hobson said:

I was wondering how long one can use the batteries once they not accepting charge properly.

Ask TTT how long his T125s been going. Been at least a year now, if you still have them? I bought them second hand in 2014, a set of 4 x T125 batteries (larger cousin to the T105, 6V). Right out of the box one cell (out of 12) had a low SG. Used them a good 18 months when suddenly one battery started doing this cliff dive every evening, doing fine and then suddenly dropping off to below 5V. Still worked fine during the day, still got me through a load shedding slot with capacity to spare.

TTT came and took the best two bats that was left in the bank. If those bats are still going, the answer to this question is "as much as 2.5 years depending on what you do with them" :-)

The 12v 350va Victron failed in the end, I bought a 24v one to avert same fiasco from happening again.

So I am keeping them happy for the day I need them again. They are on a Optimate battery charger.

Hammered them for a week with daily equalising till they where more "balanced".

14 hours ago, Chris Hobson said:

..... How long did you use them once they were finished? I was wondering how long one can use the batteries once they not accepting charge properly. Once you are at that stage you not worried about DOD so long they can power your system overnight. 

I'm still using them, but being careful, I have never let them go below 12.3V.  One of these days I'll leave the inverter on for a night and see what happens.  I'll report back then, but as TTT says, if I carry on using them as I am now, I think they'll last forever.

  • 3 weeks later...

Hi all. Im new here. Please help me. I have the following: Axpert 48v 2400w plus inv, 9 Renesola 255w panels and 4 FIAMM 180ah batteries. My question is what a safe load will be at night, i know the inverter consumes around 25w no load at night and i dont have a battery monitor, i use 3.8w globes in my house and i use 30w combined at night per hour for 12 hours ( plus the 25 the unit draws = 55w). My axpert reads 50.6v for the battery voltage about 6 in the morn.I hope im not murdering this expensive batteries...

Sent from my SM-G925F using Tapatalk

Hi Sirraven

 

Welcome

You are drawing roughly 660W/h (55W x 12 hours) which is a very low draw overnight. Those Fiamm batteries are very good batteries - worth the expense.

Your battery bank's capacity is 8640 Wh so your depth of discharge is about 24% so you are treating you batteries with love and care and still get use out of them (why you bought the batteries in the first place).

Screenshot (18).png

If we look at this table for rested batteries (your load is low and so your voltage will be close to resting voltage on can see that you are well within the green zone. This is for general lead acid batteries and one will find that the Fiamm differ slightly but you definitely not abusing your batteries. 

Thank you Chris, i feel much better now knowing my load at night is in the safe zone. During the day i draw lots more but the panels do the work :-) solar is worth the money and effort if you use it correct. Thanks.

Sent from my SM-G925F using Tapatalk

Hi Chris, i think i read you are totally off grid ? If yes what inverter and batteries do you own, is it optimal and reliable ?

Sent from my SM-G925F using Tapatalk

Hi Sirraven

I am total offgrid and have

a 4kW Axpert and

4 x 12V 260 Ah CB Solar batteries.

 260Ah (3).pdf

My system is just short of 600 days old. The inverter has not given me a moment's trouble. I think the old Axperts with the large heatsink at the top are more reliable than the newer units. Occasionally we use more than 4kW and so I will either upgrade to a 5-6kW unit or parallel a second Axpert.

My battery bank is too small for a off grid system but I knew that when I did the install. My battery bank was budget constrained and availability was an issue in June 2015. I could have reduced the PV array by 4 panels and bought extra batteries but I struggled to get the four I did get. They are rated for only 800 cycles at 50% DOD.

 

 

Your system sounds good. I agree that the old axpert is more stable. In future i would like lithuim batteries, if the axpert series can accomodate it. 20150711_201603.thumb.jpg.a7063792a3983420170204_134657.thumb.jpg.0fb113cc1a6a1020150806_105240.thumb.jpg.71cccdabc0561c20150806_105156.thumb.jpg.30fa9ce469294f

Sent from my SM-G925F using Tapatalk

1 hour ago, sirraven said:

In future i would like lithuim batteries, if the axpert series can accomodate it.
 

In Aussie the Axpert/PIP are very popular and have a large following in their electric vehicle fraternity who largely use Lithium. @Coulomb has patched the Axpert firmware to address glitches in the charging and make the system more suitable to Lithium cells.Chap on Youtube - Solar Junky is Florida based and uses Lithium.

I do have Eskom but haven't used any of it the last 2 years. At night i only use 2 x 2.4w outside lights @ 220 lumens, a ip camera 5w and clock radio 4w. I watch tv for 2 hours and that uses 30w a hour and use the house lights 3.6w each. The fridge is on extra cold during the day so at night its off. When im home weekends i use the heavy appliances. I noticed that eskom doesnt register usage below 5 watt, so i have one light on during the night inside. It all works out pretty good for me :-)

Sent from my SM-G925F using Tapatalk

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...

Account

Navigation

Search

Search

Configure browser push notifications

Chrome (Android)
  1. Tap the lock icon next to the address bar.
  2. Tap Permissions → Notifications.
  3. Adjust your preference.
Chrome (Desktop)
  1. Click the padlock icon in the address bar.
  2. Select Site settings.
  3. Find Notifications and adjust your preference.