23 hours ago, Dex_ said:

how that 220Kwh is distributed is what really makes the difference. Does this include your geyser? is your stove/oven gas?

I have a solar geyser and I never heat it with electricity. My HOB is gas and oven is electric.

I can choose the time when running the big loads (OVEN, DW, WM, IRON)

I will still be connected to the grid but want to minimize the units I buy from them.

3 hours ago, MJS said:

I have a solar geyser and I never heat it with electricity. My HOB is gas and oven is electric.

I can choose the time when running the big loads (OVEN, DW, WM, IRON)

I will still be connected to the grid but want to minimize the units I buy from them.

the oven you will need to keep on the eskom circuit likely, it just pulls too much power for you to cost effectively have it on a backup/solar system.

you basically need to decide if you want to split things off or what your maximum concurrent load will be. Frankly i think a 4000-5000W inverter will suit most home owners needs IF they are willing to have certain lifestyle adjustments. eg not ironing with the dishwasher on and turning on the microwave, if you overload the system it will trip or go to bypass.

Once you determine your size you need to determine your type and brand, there are a few options here and it depends on a few things, your goal, your technical understanding and your budget. I don't even want to get into this... there is too much debate.

Then you need to determine battery back up needs, this will depend on, your needs, your goals, your inverter and again budget.

Now you need to consider your solar side, this will be closely linked to your inverter choice potentially as many come with controllers built in and unless you have a large battery bank or a split roof setup or something you would want to use that. Then of course you will consider this with your panels.

lastly you need to consider where to course, installers, if you are in coct there is some more red tap currently, and all the extras, bracketing, cabling, susrge protection etc.

 

This is a very late post to this issue.

My installer doubled my cables from the combiner box on the roof to the inverters, this drastically cooled down those cables, could heating/overheating of wires contribute to this matter? Also the Huawei is not suitable in my honest opinion, especially only running two, three might resolve the issue as well. I did not experience so many dips even running two of those batteries.

According to my notes my settings were: 01-SBU, 02-30 (played with this between 30 and 50A), 11-20, 12-47 (48v also worked fine), 13-54 (this was too high and I set it later down to around 52v), SbL/UCb (solar charge battery 1st, my system tripped and went totally haywire the last time I had it on Solar supply load first), 26-53.2, 27-53, 29-44.5 (the reason is that the inverter give warning and sounds at 46.5 and should be back to grid at 47v, thus no warnings/errors/noise). Also no BMS was implemented at the time.   

On 2019/11/05 at 3:28 PM, Wilfred said:

, could heating/overheating of wires contribute to this matter?

Hi Wilfred, I did not read the complete post ,but want to answer on this question. Your cables should not heat up, if a cable heats up its a sign that the cable is to small and the resistance to high. This will result in additional volt drop, and the more volts you loose over the length  of the cable the less watts reaches your MPPT. 

In short, cables that is heating up, is a direct indication that some of the power your PV is generating is lost in the form of heat before it reaches your MPPT. 

Thank you @Jaco de Jongh,

Can that however be a contributing factor the the PV drop that people are experiencing?

I will go back into my log history as far as I can, I do not currently have this PV drops.
I think that I had this problem previously, but with the Huawei’s gone, no more, still need to check logs and see if the problem was actually resolved before the Huawei’s was returned.

 

16 minutes ago, Wilfred said:

Can that however be a contributing factor the the PV drop that people are experiencing?

If the volts drop below the startup voltage of the MPPT it will drop the PV, as the volts pick up the MPPT should start up again once the volts go above the Startup voltage. 

Do you perhaps have any data stored so that you can look at the voltage just before it dropped away?

Hi,

Maybe some extra info I've noticed on this issue. I have two US3000 Pylontech batteries connected to my system. Now what I've noticed, is that the PV drops don't seem to be happening during the mornings. In my case it is most likely because I switch to battery power at 10PM every night, so in the mornings the inverter is quite busy charging the batteries again.

Once the batteries are fully charged, the required PV Watts drop significantly to cater for the current load. In the example below this happened just before 1PM:

 

From this point onwards you will notice the drop in PV Watts as the load Watts spike. In most cases currently the system recovers, but I have had some instances where the PV Watts disconnects completely and all power is supplied by the batteries until I intervene.

9 hours ago, Wilfred said:

Thank you @Jaco de Jongh,

Can that however be a contributing factor the the PV drop that people are experiencing?

I will go back into my log history as far as I can, I do not currently have this PV drops.
I think that I had this problem previously, but with the Huawei’s gone, no more, still need to check logs and see if the problem was actually resolved before the Huawei’s was returned.

 

Just some feedback.

My 3 Huawei’s was replaced by 3 Neradas. I have not had any pv drop or disconnect issue since Neradas were installed. Even at varying  load during the day the pv supply stays constant.

Couldn't be happier. on a normal day batteries are fully charged by 14:00.

Cheers

 

9 hours ago, Pipes said:

Once the batteries are fully charged, the required PV Watts drop significantly to cater for the current load. In the example below this happened just before 1PM

Hmmm. But the PV drops like a stone, disappearing under another trace? I would expect the PV power to taper down, like happens at 15:00, before the battery is fully charged.

At 1PM, is the battery fully charged? Does the green charging LED (it might be different on your model) go solid, i.e. stop flashing?

On 2019/11/07 at 4:04 PM, Coulomb said:

Hmmm. But the PV drops like a stone, disappearing under another trace? I would expect the PV power to taper down, like happens at 15:00, before the battery is fully charged.

At 1PM, is the battery fully charged? Does the green charging LED (it might be different on your model) go solid, i.e. stop flashing?

This is the way it always works. Below is another example I captured today:

So once the batteries are fully charged, the PV drops like a stone, because the load drops like a stone:)

I am never around to actually monitor the charging LED at this time, but according to the Pylontech interface, both batteries are at 100% SOC.

Hi,

What are the recommended settings for my setup:

I more like off the grid , i get grid power sparingly, if everything is normal my grid power only comes when i am sleeping from 11pm-5am so i always have fully charged batteries in the morning to start my day, the rest of the day i should be on solar and batteries. I have the following:

5KVA Mecer  PF1 (5 kVA and 5 kW) 58.4 V Axpert MKS, with 145 V max MPPT.
1 Pylontech 3.5KVa battery
Less than 1kva load during  the day,  1 fridge, wifi router and TV,  the load will only come to 25% at night when i switch on the lights. i pump my water in the tank between 11pm and 5am when grid power is available
8 panels mixed (4 X 330w and 4 X375w) at peak in the day i am getting 1.5 -1.7 kw at 110v from the panels.
I would be happy if i can get recommended settings start afresh to setup the inverter.

Hi,

What are the recommended settings for my setup:

I more like off the grid , i get grid power sparingly, if everything is normal my grid power only comes when i am sleeping from 11pm-5am so i always have fully charged batteries in the morning to start my day, the rest of the day i should be on solar and batteries. I have the following:

5KVA Mecer  PF1 (5 kVA and 5 kW) 58.4 V Axpert MKS, with 145 V max MPPT.
1 Pylontech 3.5KVa battery
Less than 1kva load during  the day,  1 fridge, wifi router and TV,  the load will only come to 25% at night when i switch on the lights. i pump my water in the tank between 11pm and 5am when grid power is available
8 panels mixed (4 X 330w and 4 X375w) at peak in the day i am getting 1.5 -1.7 kw at 110v from the panels.

How can i program this setup on the attached pic

 

22 minutes ago, Petsvo said:

How can i program this setup on the attached pic

 

That's ordinary battery mode. Make sure setting 01 is SBU, and setting 12 (back to utility) is not too high. There are many posts with recommended Pylontech settings.

Only one 3.5 kWh battery is very light for a 5 kVA inverter. They only want to be charged at a maximum of about C/2, which is 1.75 kW. I don't know if the Pylontechs can enforce this, say through PWM of the big MOSFETs that presumably sit between the real battery and the battery terminals. When you can afford another Pylontech, hopefully it will use more of your available PV power.

Edited December 31, 20196 yr by Coulomb

1 hour ago, Coulomb said:

That's ordinary battery mode. Make sure setting 01 is SBU, and setting 12 (back to utility) is not too high. There are many posts with recommended Pylontech settings.

Only one 3.5 kWh battery is very light for a 5 kVA inverter. They only want to be charged at a maximum of about C/2, which is 1.75 kW. I don't know if the Pylontechs can enforce this, say through PWM of the big MOSFETs that presumably sit between the real battery and the battery terminals. When you can afford another Pylontech, hopefully it will use more of your available PV power.

HI @Coulomb sent the wrong screenshot i meant the one below:

38 minutes ago, Petsvo said:

HI @Coulomb sent the wrong screenshot i meant the one below:

I'm not aware that your Axpert MKS can perform in the mode shown, with no battery present. I thought only the models with the 450 V or 500 V max PV voltage could do that.

Do you have an online link to the manual with this image?

34 minutes ago, Coulomb said:

I'm not aware that your Axpert MKS can perform in the mode shown, with no battery present. I thought only the models with the 450 V or 500 V max PV voltage could do that.

Do you have an online link to the manual with this image?

https://portal.segensolar.co.za/reseller/docs/Axpert-MKSII_5KVA_manual.pdf

11 hours ago, Petsvo said:

https://portal.segensolar.co.za/reseller/docs/Axpert-MKSII_5KVA_manual.pdf

That's a manual for an MKS II, you said you own one with a 145 V max Solar Charge Controller. They are different beasts, with different capabilities. Yours cannot run without a battery, the MKS II can.

11 hours ago, Coulomb said:

That's a manual for an MKS II, you said you own one with a 145 V max Solar Charge Controller. They are different beasts, with different capabilities. Yours cannot run without a battery, the MKS II can.

Eish that's bad, so i need a new inverter, i have taken pylontech recommended settings and applied, but the inverter is now complaining error 4 ( battery voltage too low) 

 

On 2020/01/01 at 10:24 PM, Petsvo said:

Eish that's bad, so i need a new inverter,

? Why is that?

Quote

i have taken pylontech recommended settings and applied, but the inverter is now complaining error 4 ( battery voltage too low) 

The recommended value for setting 29 (low battery voltage cutoff) is too high. You will get low battery warnings at 2.0 V higher than that figure (undocumented). See FAQ question 1.

Just use a lower value for setting 29. About 2.5 V lower than setting 12 is good.

Edited July 9, 20205 yr by Coulomb

13 hours ago, Coulomb said:

? Why is that?

The recommended value for setting 29 (low battery voltage cutoff) is too high. You will get low battery warnings at 2.0 V higher than that figure (undocumented). See FAQ question 1.

Just use a lower value for setting 29. About 2.5 V lower than setting 12 is good.

These are my setting after the forum recommendation :

01: SOL

02: 40A

05 User

11: 40 A

12: 48v

13: 51v (what happens if it goes lower, i want the PV to stay online more than running on battery, so that i can save them for the long night)

16: CSO

26: 54.8, forum remedy for PV freeze

27: 54.  forum remedy for PV freeze

28: SI G

29: 45 ( 2 volt threshold 4 volt threshold for program 12 and 13)

17 hours ago, Petsvo said:

These are my setting after the forum recommendation :

01: SOL

02: 40A

05 User

11: 40 A

12: 48v

13: 51v (what happens if it goes lower, i want the PV to stay online more than running on battery, so that i can save them for the long night)

16: CSO

26: 54.8, forum remedy for PV freeze

27: 54.  forum remedy for PV freeze

28: SI G

29: 45 ( 2 volt threshold 4 volt threshold for program 12 and 13)

Hi @Petsvo 

From reading your post you are probably in Zimbabwe and are lucky if you get grid power at all. With that in mind the settings above probably won't work for you, you will need the grid to assist whenever it's available. As has been pointed out elsewhere one 3.5kwh pylontech battery is not really sufficient to manage you needs when the sun has gone. ( you really need one more). With only the1 x 3.5 battery I suggest your load be reduced to under 300watts from about 4pm.  Here is what I set to :-

01: Uti

02: 30

05: user

11: 30

16: SNU

26: 53.2v ( It has been suggested by a solar company in SA that their tests indicate pylon batteries don't like higher bulk voltages)

27: 52.7

29: 42

 

 

On 2020/01/03 at 9:53 AM, Nostromo said:

Hi @Petsvo 

From reading your post you are probably in Zimbabwe and are lucky if you get grid power at all. With that in mind the settings above probably won't work for you, you will need the grid to assist whenever it's available. As has been pointed out elsewhere one 3.5kwh pylontech battery is not really sufficient to manage you needs when the sun has gone. ( you really need one more). With only the1 x 3.5 battery I suggest your load be reduced to under 300watts from about 4pm.  Here is what I set to :-

01: Uti

02: 30

05: user

11: 30

16: SNU

26: 53.2v ( It has been suggested by a solar company in SA that their tests indicate pylon batteries don't like higher bulk voltages)

27: 52.7

29: 42

 

 

thanks i will change to these settings and report back

 

On 2020/01/01 at 3:06 AM, Coulomb said:

That's a manual for an MKS II, you said you own one with a 145 V max Solar Charge Controller. They are different beasts, with different capabilities. Yours cannot run without a battery, the MKS II can.

@Coulomb kindly help if this is the right inverter( MKSII) SOL-I-AX-5NB MECER HYBRID  II    5000VA/5000W  Solar Inverter/ UPS   4 000W MPPT 220V      48V DC  PF1   150V-400V MPPT. I need to swap the current inverter with the one that you referred above.

 

 

Edited January 7, 20206 yr by Petsvo
typo

3 hours ago, Petsvo said:

@Coulomb kindly help if this is the right inverter( MKSII) SOL-I-AX-5NB MECER HYBRID  II    5000VA/5000W  Solar Inverter/ UPS   4 000W MPPT 220V      48V DC  PF1   150V-400V MPPT.

It matches the Axpert MKS II, which is the one that you linked a manual to. So yes, if you want an Axpert MKS II, the SOL-I-AX-5NB from Mecer is the same thing. I wish each reseller would keep the original model name and number.

I note that it will require much higher voltage for the panels compared to the one you have now; the one you have now is 145 V max, the MKS II is 450 V max. So if you've already configured panels for the 145 V model, some rewiring will be required for the MKS II. If you've not wired any panels yet, that's good; the MKS II has simpler wiring (just string between about 5 and 10 panels in series, the lower and upper limit depending on the specs of the panels.

Thanks, i will need to re-arrange the connectors, i have 8 panels wired to produce 110 volts, grouped into 4s then connected in parallel into the inverter. So the biggest drawback on this inverter is that if voltage goes below 145 the PV power will shut down.