islamics:

Thanks for the reply. I did exactly like that but it didn't work.
I just took it for repair and realized most of the capacitor responsible for the charging were burnt. I didn't connect the stuff via stabilizer.
Na fixing level now though repairman say chance of it working well na 50/50.

If he knew his work well, it should work 100%.

ceaser:


@bolded is quite untrue.

The MC4s are designed to ensure perfect and fit contact with themselves. They are weatherproof and designed to last the lifetime of the panel. They are also rated to handle the current that flows from the panels. That is why arcing is quite uncommon at their points of contacts when used in installation, whereas the naked wires (after the MC4s are decapitated) will form arcs when huge current passes across the twist junction. This gradually weakens the joint and eventually the joint burns out, disrupting flow from the panels down to the CC, [/b]hence your voltmeter may give correct voltage reading at the termination on the CC, but no current will be detected by the CC. The naked wires too (even with black tape insulation used), are prone to oxidation as they get exposed to the elements.

[b]So if the problem of arcing does not occur soon, oxidation will definitely come along later. The wire develops depositions, the strands become brittle and break off easily. You don't want to have this kind of problem if your panels are roof mounted where they are not within easy reach.

The bolded are so very untrue sir...

We need to learn to buttress some points here without outrightly condemning some methodology here; especially methods that have worked and IS still working.
It is true that using MC4 connector is a very fine and commendable method for joining external cables to panel own.

It is also true that cutting off the panel cable and joining by twisting can cause some or all of your points, buy that's not always the case. You made it sound general. After all, whether you want to believe it or not, people have used MC4 and ended up with more wahala of no-contact or using inferior connector, which also results to some or all your points too.

EVERYTHING depends on quality of material used and skill of the installer!!!

Over 7 years, I've installed so many hundreds of panels and I never, for once, use MC4 connector for any installation. And for 5 years plus, I've ALWAYS handled all connections myself untill I was sure my guys can do it satisfactorily to my standard. As a matter of fact, only one of my guys can do that and he's the only one that can do connection aside myself.

I did installation for one client.. 5 years later, while he was changing his batteries, he decided to add more panels. During the upgrade, the told me he noticed I cut the cables and that he would like me to use MC4 for the upgrade; that he's heard about the concerns you just pointed out. However, I asked him if his panel performance has dropped at any time, and he said no.
However, I took him to the old connections and I gradually removed all the double layer insulations on ALL joints and I asked him to see if there's any form of degradation. Bros, all joints were still much intact. The insulation tape didn't degrade. The cables were still looking good; none was looking dark or corroded.
That's how the man allowed me to do my thing.

Now, I'm going to explain how exactly I do my connections using pictures. Pictures attached were taken 2 years ago, which I use for classroom explanations during my Training sessions. Follow the pictures according to the numbers.

The only thing I want to add is this; most twisted connections have issues because most installers lack the skill and patience of proper cable joining. I've giving opportunity to some electricians and their twisting and insulating mannerism is just very local and road-side.

Referring to the pictures, after twisting together the strands in Pic 4, I first use an "A Grade" flame retardant white insulation tape for the first taping (pic 5) I buy this tape at N750 at ShopRite. Then I use an original Scotch tape to do the 2nd and final taping (pic 6). See pic 8 for the tapes

You can't use all this N50 insulation tape and won't expect it to untape (or unwind) as times go on. And during taping, ensure you tension the tape.

For the exposure, I always ensure I tie cables to the rail, and I ensure all joint sides are directly covered by the panels. Sun or rain, none would near it.

So, guy, there's absolutely nothing wrong with cutting off and joining. As long as you use the proper and professional method or joining. Even the National Electrical Code (NEC) and British Standard Code still have joining methods with different methodology like T-method, Married method etc... People should learn how to properly remove insulation, divide strands, and join cables. Then also, properly insulate them.
And while insulating, give like 1inch gap down before you start insulating and work your way upwards,applying tension and leaving no single air-gap.

Each year I go for maintenance (panel washing ) for clients, I inspect everything.... And always, all is intact and still performing optimally.

Finally, one thing with cutting off the head would help you with is identifying if the panel you bought comes with copper (whether pure copper or tinned copper) or aluminium.
Some years back, one man asked me to help check his set-up installed by somebody. The panels were just over 2years but no protection again. Like, the MPPT was not charging again and he was wondering whether the MPPT was bad. After troubleshooting, I told him that nothing is wrong with the MPPT and the problem could be that something is wrong somewhere with the Array.
Right on the roof, I started disconnecting the panels to test them one after the other. And yes, MC4 was used. First 2 panels were okay but the 3rd one in the string wasn't reading any voltage. Out of 9panels, 6 were not reading.

We now brought down all the panels. I decided to open the black boxes and test directly, bypassing the cables. Mehn, see decay! Cable has decayed at the point it's connected to the diode assembly and has literally decayed off. The cables were ALUMINIUM cables!!!

In summary, we changed all cables and soldered copper cables to the diode assembly. That solves it. However, the man later changed all the panels...

I've also had one client that bought Joysolar panels sometime and asked me to come and install. After cutting the first head and realising the cable was aluminium, we jejely changed all cables on all 12panels. And the annoying part is that, the aluminium is ALWAYS coated with copper colour. Not until you handle it, and then you'll realise it's aluminium.... That's is, if you can actually be able to differentiate

However, when you buy original panels from original source, you won't have doubt as to whether they came with Copper or Aluminium. They always come with copper (pure or tinned).

Whichever case, I love cutting and twist-joining... Trust me, some twist-joining outlasts some MC4 connections...

Whatever anyone finds comfortable, the key thing is the professionalism you applied in whatever method .. Cheers

Valto:
yes, whatsapp me

Can’t find a number to reach you at. Is there a reason why the number cannot be shared here?

we can now assemble in high quality HDF wooden box at very cheap prices,metal boxes will be available soon
12v 100ah/105ah assembled in a nice HDF wooden box,quality JBD 120A bms, 10mm battery terminals, voltmeter and quality cables =175k/180k

---

24v 100ah/ 105ah assembled in nice HDF wooden box. 24v 8s quality 120A JBD bms. 10mm battery terminals and quality cables =320k/335k. note:we use only brand new real capacity Grade A lifepo4 cells.
whatsapp me 0802-057-4628

mcTrinity:




Referring to the pictures, after twisting together the strands in Pic 4, I first use an "A Grade" flame retardant white insulation tape for the first taping (pic 5) I buy this tape at N750 at ShopRite. Then I use an original Scotch tape to do the 2nd and final taping (pic 6). See pic 8 for the tapes

You can't use all this N50 insulation tape and won't expect it to untape (or unwind) as times go on. And during taping, ensure you tension the tape.

The ₦50 tape is no longer ₦50

I like the flame retardant tape you use, ideal for roof mounted installation where the roof will get super hot on sunny days.

Good job here

To the gurus in the house
Please what should be the back panel settings for a Microtek 2300 inverter 24V GSR 240ah tubular (2) batteries
1, should the float charging voltage be set to high or standard.
2, should charging current be set to high charging or low charging
Thank you

HeadofNairaland:


If he knew his work well, it should work 100%.

I am thinking that na bargain tactics sef.

Valto:
we can now assemble in high quality HDF wooden box at very cheap prices,metal boxes will be available soon
12v 100ah/105ah assembled in a nice HDF wooden box,quality JBD 120A bms, 10mm battery terminals, voltmeter and quality cables =175k/183k

---

24v 100ah/ 105ah assembled in nice HDF wooden box. 24v 8s quality 120A JBD bms. 10mm battery terminals and quality cables =320k/335k. note:we use only brand new real capacity Grade A lifepo4 cells.
whatsapp me 0802-057-4628

Wow! This is impressive! Weldone, boss

darediamond:
Does Natural Coal Get Formed In An Open Surface?
How come you expect to get quality man-made coal from burning wood in Air?

See, my directions are meant for individuals who are ready to GET THERE HANDS DIRTY LIKE I'M DOING MYSELF TO KEEP DISCOVERING SERIES OF WONDERS.

IF YOU DO NOT UNDERSTAND SOMETHING, YOU ASK QUESTIONS not that you become [b]unnecessarily arrogant [/b]at the person providing you with his or her own discovery.

Have you even tried what I explained on how to get the said effect at all?

Come on!!!

See, I said it. You don't know how to talk, or perhaps you find it difficult to express yourself smoothly and innocously in English, and I won't blame you if the reason is the latter.

Abegi, I no get time drag anything further jàre. If you like, manufacture Sodium Manganese battery or even wood-metal-hydride battery, its good thing for us and we will give you the recognition you crave for that.

Members on the thread have had to contend with worse from some party crashers before who once in a blue moon drop by here and yet the discussions on here still goes on strongly.

Bye bye.

ceaser:


See, I said it. You don't know how to talk, or perhaps you find it difficult to express yourself smoothly and innocously in English, and I won't blame you if the reason is the latter.

Abegi, I no get time drag anything further jàre. If you like, manufacture Sodium Manganese battery or even wood-metal-hydride battery, its good thing for us.

Bye.

You sha get energy

saint2ace:



You sha get energy

Bro you no lie and sincerely I blame myself. I thought he would understand where I'm coming from but he is hyper-excited and too fixated on his "novel discoveries".

I think we need to encourage him to carry on with his researches, àbí. More power to his elbows. More fire to his vaccum oven. More activated charcoal to his vaccum oven.

ceaser:


Bro you no lie and sincerely I blame myself. I thought he would understand where I'm coming from but he is hyper-excited and too fixated on his "novel discoveries".

I think we need to encourage him to carry on with his researches, àbí. More power to his elbows. More fire to his vaccum oven. More activated charcoal to his vaccum oven.

Lolz, just let it slide boss. Water must find him level......

mcTrinity:


The bolded are so very untrue sir...

We need to learn to buttress some points here without outrightly condemning some methodology here; especially methods that have worked and IS still working.
It is true that using MC4 connector is a very fine and commendable method for joining external cables to panel own.

It is also true that cutting off the panel cable and joining by twisting can cause some or all of your points, buy that's not always the case. You made it sound general. After all, whether you want to believe it or not, people have used MC4 and ended up with more wahala of no-contact or using inferior connector, which also results to some or all your points too.

EVERYTHING depends on quality of material used and skill of the installer!!!

Over 7 years, I've installed so many hundreds of panels and I never, for once, use MC4 connector for any installation. And for 5 years plus, I've ALWAYS handled all connections myself untill I was sure my guys can do it satisfactorily to my standard. As a matter of fact, only one of my guys can do that and he's the only one that can do connection aside myself.

I did installation for one client.. 5 years later, while he was changing his batteries, he decided to add more panels. During the upgrade, the told me he noticed I cut the cables and that he would like me to use MC4 for the upgrade; that he's heard about the concerns you just pointed out. However, I asked him if his panel performance has dropped at any time, and he said no.
However, I took him to the old connections and I gradually removed all the double layer insulations on ALL joints and I asked him to see if there's any form of degradation. Bros, all joints were still much intact. The insulation tape didn't degrade. The cables were still looking good; none was looking dark or corroded.
That's how the man allowed me to do my thing.

Now, I'm going to explain how exactly I do my connections using pictures. Pictures attached were taken 2 years ago, which I use for classroom explanations during my Training sessions. Follow the pictures according to the numbers.

The only thing I want to add is this; most twisted connections have issues because most installers lack the skill and patience of proper cable joining. I've giving opportunity to some electricians and their twisting and insulating mannerism is just very local and road-side.

Referring to the pictures, after twisting together the strands in Pic 4, I first use an "A Grade" flame retardant white insulation tape for the first taping (pic 5) I buy this tape at N750 at ShopRite. Then I use an original Scotch tape to do the 2nd and final taping (pic 6). See pic 8 for the tapes

You can't use all this N50 insulation tape and won't expect it to untape (or unwind) as times go on. And during taping, ensure you tension the tape.

For the exposure, I always ensure I tie cables to the rail, and I ensure all joint sides are directly covered by the panels. Sun or rain, none would near it.

So, guy, there's absolutely nothing wrong with cutting off and joining. As long as you use the proper and professional method or joining. Even the National Electrical Code (NEC) and British Standard Code still have joining methods with different methodology like T-method, Married method etc... People should learn how to properly remove insulation, divide strands, and join cables. Then also, properly insulate them.
And while insulating, give like 1inch gap down before you start insulating and work your way upwards,applying tension and leaving no single air-gap.

Each year I go for maintenance (panel washing ) for clients, I inspect everything.... And always, all is intact and still performing optimally.

Finally, one thing with cutting off the head would help you with is identifying if the panel you bought comes with copper (whether pure copper or tinned copper) or aluminium.
Some years back, one man asked me to help check his set-up installed by somebody. The panels were just over 2years but no protection again. Like, the MPPT was not charging again and he was wondering whether the MPPT was bad. After troubleshooting, I told him that nothing is wrong with the MPPT and the problem could be that something is wrong somewhere with the Array.
Right on the roof, I started disconnecting the panels to test them one after the other. And yes, MC4 was used. First 2 panels were okay but the 3rd one in the string wasn't reading any voltage. Out of 9panels, 6 were not reading.

We now brought down all the panels. I decided to open the black boxes and test directly, bypassing the cables. Mehn, see decay! Cable has decayed at the point it's connected to the diode assembly and has literally decayed off. The cables were ALUMINIUM cables!!!

In summary, we changed all cables and soldered copper cables to the diode assembly. That solves it. However, the man later changed all the panels...

I've also had one client that bought Joysolar panels sometime and asked me to come and install. After cutting the first head and realising the cable was aluminium, we jejely changed all cables on all 12panels. And the annoying part is that, the aluminium is ALWAYS coated with copper colour. Not until you handle it, and then you'll realise it's aluminium.... That's is, if you can actually be able to differentiate

However, when you buy original panels from original source, you won't have doubt as to whether they came with Copper or Aluminium. They always come with copper (pure or tinned).

Whichever case, I love cutting and twist-joining... Trust me, some twist-joining outlasts some MC4 connections...

Whatever anyone finds comfortable, the key thing is the professionalism you applied in whatever method .. Cheers

Okay sir. No wàhálà na.

justcallmenuel:
200w sun field floodlight available, #41,000. Call/WhatsApp us on 08168986461

How many Lumens is this Floodlight?

To the gurus in the house
Please what should be the back panel settings for a Microtek 2300 inverter 24V (GSR 240ah tubular (2) batteries)
1, should the float charging voltage be set to high or standard.
2, should charging current be set to high charging or low charging
Thank you

Greetings to the Gurus...
I have a centurion automatic gate which I always find it difficult to use due to lack of Electricity(we all know what light has become in Nigeria now)
please I want to know the material needed to use Solar. I.e. The capacity of the Panel e.t.c
The battery is 12V 7.2Ah
I already have a solar controller.

Vahyela:
Greetings to the Gurus...
I have a centurion automatic gate which I always find it difficult to use due to lack of Electricity(we all know what light has become in Nigeria now)
please I want to know the material needed to use Solar. I.e. The capacity of the Panel e.t.c
The battery is 12V 7.2Ah
I already have a solar controller.

What is the motor power in watts? can you find it? Charging a 7.2AH battery any small 12v panel below 200W would comfortably do that


From their site their solar kit recommends a 40W panel
Solar kit includes:
1 x 12V Operator (comes standard with Foundation Plate, Controller, 1.8A SM Charger, 2 x 4 Button NOVA Transmitters, 4 x 1m modules of CP20N4 / Stagnoli Gear Rack)
1 x 33Ah Battery
1 x Battery Enclosure
1 x 40W Solar Panel
1 x Solar Panel Bracket
1 x Solar Regulator
1 x Solar Panel Connector Kit
https://gateandfencehardware.com.au/product/d5-centurion-centsys-evo-sliding-gate-motor/

FireTheSun:


I just got delivery of 32 Units of 280Ah Cells from a Supplier in China.
I will recommend you use the Company.
Just search for Shenzen New Dery Energy Company, on alibaba.
The name of the Lady is "Selina Li".

I had an issue with 4Cells in the delivery because the Shipper she used, allowed 4Cells to be damaged, outof the 32 Cells and the Clearance in Lagos was a bit high but l got to know that she had changed the Shipper to a better one now.
Her Guaranty is also good as she is replacing the damaged Cells.
A few people here are expecting some shipment from her in a two-three Months from now.

If you reach her on time, she might be able to pack your purchase in the current Shipment.

BTW: I got introduced to her by @valto.

Hello, I searched for this company and they are nowhere to be found on Alibaba. Is there issue of spelling?
Thanks

auwal8377:

Hello, I searched for this company and they are nowhere to be found on Alibaba. Is there issue of spelling?
Thanks

I think this is the company he's taking of

https://dery.m.en.alibaba.com/

mctfopt:



I think this is the company he's taking of

https://dery.m.en.alibaba.com/

I got it. Thank you Bro.

Vahyela:
Greetings to the Gurus...
I have a centurion automatic gate which I always find it difficult to use due to lack of Electricity(we all know what light has become in Nigeria now)
please I want to know the material needed to use Solar. I.e. The capacity of the Panel e.t.c
The battery is 12V 7.2Ah
I already have a solar controller.

Is your sliding gate opener provisioned to use battery (DC powered)?

If its AC only, then you should be looking at around 180 watts motor and around 250 watts peak per cycle.

But if it is provisioned for DC power (AC/DC/solar), then the motor should be circa 80 watts.

You may need to use a watt meter to be sure of the true consumption though.

I use a 12v/24v DC/solar powered model (with in built charge controller) after retiring an AC powered one, though none of the two are "centurion" model.

Your 12v 7.2ah may power it, but the backup will be quite short. The quiesent current draw of my AC opener was around 4 watts, then the dedicated 24v inverter also consumes 8 watts, so by morning the 24v 12ah battery backup is flat. So I was forced to retire it.

The DC opener has a slot for 12v 6ah battery, but I decided to construct a 24v 20ah Li-ion pack for it. The voltage of the pack has never gone below 25v ever since it was connected to it. Its charged by 2s 12v 40 watts panel. I use an external PWM controller, not the in built one. I believe not using the in built CC will prolong the life of the board although I already bought an extra board as stand by against the rainy day.

Please my senior engineer's is like Felicity lithium battery is not up to the rating capacity am using two 5kwa Felicity lithium battery up to 10kwa but it not carrying 1400w load up to 5hrs after full charged.from my calculations it supposed to carry the load up to7hrs.pls is anything am missing in my calculations?
I need your advice please

ceaser:


See, I said it. You don't know how to talk, or perhaps you find it difficult to express yourself smoothly and innocously in English, and I won't blame you if the reason is the latter.

Abegi, I no get time drag anything further jàre. If you like, manufacture Sodium Manganese battery or even wood-metal-hydride battery, its good thing for us and we will give you the recognition you crave for that.

Members on the thread have had to contend with worse from some party crashers before who once in a blue moon drop by here and yet the discussions on here still goes on strongly.

Bye bye.

And it is you who "know how to talk" ba?
It is not a must for you to reply over what you know nothing about.

I crave for no attention from you or your likes on this thread.
Cheaper DIY Solutions to General Constant Power Outage in this part of the world named Nigeria is my keen desire as NO MAN IS AN ISLAND.

Are you the only one on this thread?

What I do not know solution to, I try to find solution to and there are people in similar situation in silence. So if I share what I know in a concentrated nor diluted manner how is that bad?

Even if I come down to your own preferred level of explanation of my personal findings, NEVER WILL THE ACCUTE CHRONIC ARROGANCE in you allow you to ask questions of what you do not understand about whatever I choose to say or revealed.

You KNOW NOT HOW TO CREATIVELY CRITICIZE AT ALL Mr English.

Anyways, greetings to you and your likes in "Sodium Manganese" and or "wood-metal-hydride".

emyfine08:
Please my senior engineer's is like Felicity lithium battery is not up to the rating capacity am using two 5kwa Felicity lithium battery up to 10kwa but it not carrying 1400w load up to 5hrs after full charged.from my calculations it supposed to carry the load up to7hrs.pls is anything am missing in my calculations?
I need your advice please

that is the reason most people on this thread prefer to couple thier own cells from scratch, because just like many panels in the market are fake capacity, most lithium brands marketed in Nigeria, are also fake capacity. some are assembled with low quality cheap/used cells. that declared 5kwh might be around 3.8kwh.u just have to manage it like that.. kpele

...

Good day,
I have been reading a lot about Felicity Lifepo4 battery capacity but I can state most of the statements are not totally true. The one i'm using is 5KWH (Model: LPBT24250 Usable Capacity 5KWH written on the box), I had consumed more 200AH from it more than twice before turning the inverter off myself. Although I set the capacity to 200AH on my BMV 702 initially because of the comments I read on this platform that their batteries capacity are not true capacity, but I have changed to 250AH after several capacity test. Reason my battery SOC is showing Zero in atatched pictures.

From my understanding, they have several models of batteries with same voltage at different prices but you need to do own research on the batteries.

I will advise the OP to check the inverter cut off time if it's set to like 50%.

PS:

I'm an end user and I have no relationship with Felicity.

emyfine08:
Please my senior engineer's is like Felicity lithium battery is not up to the rating capacity am using two 5kwa Felicity lithium battery up to 10kwa but it not carrying 1400w load up to 5hrs after full charged.from my calculations it supposed to carry the load up to7hrs.pls is anything am missing in my calculations?
I need your advice please

ebocoms:
Good day,
I have been reading a lot about Felicity Lifepo4 battery capacity but I can state most of the statements are not totally true. The one i'm using is 5KWH (Model: LPBT24250 Usable Capacity 5KWH written on the box), I had consumed more 200AH from it more than twice before turning the inverter off myself. Although I set the capacity to 200AH on my BMV 702 initially because of the comments I read on this platform that their batteries capacity are not true capacity, but I have changed to 250AH after several capacity test. Reason my battery SOC is showing Zero in atatched pictures.

From my understanding, they have several models of batteries with same voltage at different prices but you need to do own research on the batteries.

I will advise the OP to check the inverter cut off time if it's set to like 50%.

PS:

I'm an end user and I have no relationship with Felicity.

Thanks for sharing your experience. The battery is rated for 200Ah. How much were you able to pull out of the battery from 100% fully charged? I did not really get that from your post.

I pulled 209AH on that day but had to turned off the inverter manually that day. You can see it from my customized emoncms picture attached (Day Deepest Discharged). The data is from my BMV 702.

bigrovar:

Thanks for sharing your experience. The battery is rated for 200Ah. How much were you able to pull out of the battery from 100% fully charged? I did not really get that from your post.

[quote author=mcTrinity post=112952101]

The bolded are so very untrue sir...

We need to learn to buttress some points here without outrightly condemning some methodology here; especially methods that have worked and IS still working.
It is true that using MC4 connector is a very fine and commendable method for joining external cables to panel own.

It is also true that cutting off the panel cable and joining by twisting can cause some or all of your points, buy that's not always the case. You made it sound general. After all, whether you want to believe it or not, people have used MC4 and ended up with more wahala of no-contact or using inferior connector, which also results to some or all your points too.

EVERYTHING depends on quality of material used and skill of the installer!!!

Over 7 years, I've installed so many hundreds of panels and I never, for once, use MC4 connector for any installation. And for 5 years plus, I've ALWAYS handled all connections myself untill I was sure my guys can do it satisfactorily to my standard. As a matter of fact, only one of my guys can do that and he's the only one that can do connection aside myself.

I did installation for one client.. 5 years later, while he was changing his batteries, he decided to add more panels. During the upgrade, the told me he noticed I cut the cables and that he would like me to use MC4 for the upgrade; that he's heard about the concerns you just pointed out. However, I asked him if his panel performance has dropped at any time, and he said no.
However, I took him to the old connections and I gradually removed all the double layer insulations on ALL joints and I asked him to see if there's any form of degradation. Bros, all joints were still much intact. The insulation tape didn't degrade. The cables were still looking good; none was looking dark or corroded.
That's how the man allowed me to do my thing.

Now, I'm going to explain how exactly I do my connections using pictures. Pictures attached were taken 2 years ago, which I use for classroom explanations during my Training sessions. Follow the pictures according to the numbers.

The only thing I want to add is this; most twisted connections have issues because most installers lack the skill and patience of proper cable joining. I've giving opportunity to some electricians and their twisting and insulating mannerism is just very local and road-side.

Referring to the pictures, after twisting together the strands in Pic 4, I first use an "A Grade" flame retardant white insulation tape for the first taping (pic 5) I buy this tape at N750 at ShopRite. Then I use an original Scotch tape to do the 2nd and final taping (pic 6). See pic 8 for the tapes

You can't use all this N50 insulation tape and won't expect it to untape (or unwind) as times go on. And during taping, ensure you tension the tape.

For the exposure, I always ensure I tie cables to the rail, and I ensure all joint sides are directly covered by the panels. Sun or rain, none would near it.

So, guy, there's absolutely nothing wrong with cutting off and joining. As long as you use the proper and professional method or joining. Even the National Electrical Code (NEC) and British Standard Code still have joining methods with different methodology like T-method, Married method etc... People should learn how to properly remove insulation, divide strands, and join cables. Then also, properly insulate them.
And while insulating, give like 1inch gap down before you start insulating and work your way upwards,applying tension and leaving no single air-gap.

Each year I go for maintenance (panel washing ) for clients, I inspect everything.... And always, all is intact and still performing optimally.

Finally, one thing with cutting off the head would help you with is identifying if the panel you bought comes with copper (whether pure copper or tinned copper) or aluminium.
Some years back, one man asked me to help check his set-up installed by somebody. The panels were just over 2years but no protection again. Like, the MPPT was not charging again and he was wondering whether the MPPT was bad. After troubleshooting, I told him that nothing is wrong with the MPPT and the problem could be that something is wrong somewhere with the Array.
Right on the roof, I started disconnecting the panels to test them one after the other. And yes, MC4 was used. First 2 panels were okay but the 3rd one in the string wasn't reading any voltage. Out of 9panels, 6 were not reading.

We now brought down all the panels. I decided to open the black boxes and test directly, bypassing the cables. Mehn, see decay! Cable has decayed at the point it's connected to the diode assembly and has literally decayed off. The cables were ALUMINIUM cables!!!

In summary, we changed all cables and soldered copper cables to the diode assembly. That solves it. However, the man later changed all the panels...

I've also had one client that bought Joysolar panels sometime and asked me to come and install. After cutting the first head and realising the cable was aluminium, we jejely changed all cables on all 12panels. And the annoying part is that, the aluminium is ALWAYS coated with copper colour. Not until you handle it, and then you'll realise it's aluminium.... That's is, if you can actually be able to differentiate

However, when you buy original panels from original source, you won't have doubt as to whether they came with Copper or Aluminium. They always come with copper (pure or tinned).

Whichever case, I love cutting and twist-joining... Trust me, some twist-joining outlasts some MC4 connections...

Whatever anyone finds comfortable, the key thing is the professionalism you applied in whatever method .. Cheers

* Thank you for this.

ebocoms:
I pulled 209AH on that day but had to turned off the inverter manually that day. You can see it from my customized emoncms picture attached (Day Deepest Discharged). The data is from my BMV 702.

Maybe one day you can do a full discharge capacity test

emyfine08:
Please my senior engineer's is like Felicity lithium battery is not up to the rating capacity am using two 5kwa Felicity lithium battery up to 10kwa but it not carrying 1400w load up to 5hrs after full charged.from my calculations it supposed to carry the load up to7hrs.pls is anything am missing in my calculations?
I need your advice please

what type of inverter are you using?
hope you configured it properly to charge lifepo4 battery?

felicity uses different battery types in their packs, some good, most fair..and a few downright not good.
so yours might be among the few good ones, if everyother thing check d out ok. hv seen felicity pack with cheap used byd cell packs inside