mctfopt:



I've seen a small pack of 1kwh lithium gut a shop. Everything inside was gone. This happened in the afternoon with people around. Battery fire is no joke. Hence best to use the best of everything. The cause of the fire was charging the battery directly without a charge controller.

mctfopt:

Lithium ion..

GloriousGbola:


Please get an earth resistance tester and confirm the earthing. It should have a resistance of less than 10 ohms or if it is very good 5 ohms. We found that one of our installations had a resistance of 15 ohms and we had to use four earth rods and bentonite to resolve this.

twinskenny:


with srne 3kw or 3.3kw you can never go wrong my friend

GloriousGbola:


Last I checked a bag is like 20k to 25k. Check jiji .though as a naija matter I don't even know if it is real bentonite. What I can say is after 4 earth rods driven deeper, an earth mat and bentonite we went from 20+ ohms to 9 Ohms. Thought it was waterlogged clayey soil.

HeavenlyBang:


3.3kw is a much better deal than the 3kw.

80a vs 60a CC, 4000w PVs vs 1400w as well.

For less than 100k more.

twinskenny:


with srne 3kw or 3.3kw you can never go wrong my friend

tsiriman:


I know three people that bought the 24V iPower max and the inverter didn't last more than a day in 2 of the cases, inverter got damaged and they had to return it. The third person used his for less than 2 weeks and it developed a fault that he had to change the inverter, my advice is don't buy the iPower 24V, look at other brands.

On the flip side i know a number of people using the iPower 48V without any issues at all.

Stay away from the 24V of that brand

Trippledots:


Anger is good when our into productivity..lol

NpvnStar:


omo, been rocking the stabilizer, I might just start it up as a business for a fraction of the profits. at least lets improve the quality of products we get on nairaland.

mctfopt:


TND do great stabilisers. I think they are in the league of Stavol.

Drgreatone:
Hello house. Kinda need ur advice here.
I av a friend who I'm sure wud be reading this. Had this old sch 5kva48v felicity inverter with VOC of 145v with 9 pcs of 270w panel connected 3s3p. He later added 2 625w panels which were joined in series and then connected in parallel to the previous 9panels. Now he's gotten a 10kva sms inverter with max voc of 500v and he wants to series all the panels together. What are the possible pros and cons? Not comfortable with the arrangement but he feels it would work.
Thanks in advance
Panel specs:
625w VOC 56.56 ISC 13.6 VMP 47.93 IMP 13.05
270w VOC 37.44 ISC 9.09 VMP 31.2 IMP 8.65

FEGEITOK:


One earth rod.

The panels are next to the house but not on the roof.

What I have noticed is that anything that happens to any electrical circuit whether mains side or PV side the RCCB trips off.

jonescosmos:
SEE ATTACHED PICTURES,
NOTE THAT THERE WILL BE ENERGY LOSSES NO MATTER HOW HE CHOOSE TO STRING HIS PANELS

GloriousGbola:


Please get an earth resistance tester and confirm the earthing. It should have a resistance of less than 10 ohms or if it is very good 5 ohms. We found that one of our installations had a resistance of 15 ohms and we had to use four earth rods and bentonite to resolve this.

bigrovar:


Please don't go broke trying to get sub 10 ohms earth resistance. For a TT system at least going by UK electric code for residential systems. (We use TT earthing system in Nigeria)

Minium theoretical earth electrode resistance is actually 1666 Ohms. Now that is theoretical. In practice anything below 200 ohms is considered ok but below 100 ohms is recommended.

10 ohms and below are requirement for industrial applications and power equipments line transformers, power substations, Network Masts etc.

They are not a requirement for home earthing of electrical components. To get anything below 10 ohms for domestic earth rod would be very expensive.

The important thing to note in all of this is that. Homes are required to use RCDs to compliment a domestically installed earthing system.

This helps to provide protection in place of a very low earth electrode set out to provide ie trip a breaker in the case of an earth fault. Since 100 ohms earth rod is incapable of tripping a breaker. An RCD does that job

Source

https://www.tlc-direct.co.uk/Book/8.6.1.htm

https://community.screwfix.com/threads/tt-earthing-readings.173423/

https://www.quora.com/In-a-TT-earthing-system-how-does-the-fault-current-go-through-the-consumer-earth-rod-to-source-the-earth-rod-through-the-earth-because-the-earth-s-resistance-is-too-high



If your RCD trips then that is a bigger issue with your electrical connection which needs to be fixed and not a or problem with your earthing.


Secondly lots of people including me use to go all in on likes of bentonite and GEMs. Until I realize just drilling your earth rod into the ground should be sufficient..

See compacted earth and length of earth rod matters more than some of these Earthing materials. From all the literature I have read on the issue, getting an 8 foot earth rod (copper bonded is fine and stronger than all copper earth rod which can be quite brittle)

Just drilling your earth rod on undisturbed compacted soil ensures the earth is fine.
At least you can carry out soil resistant before you start.
If you live in a place of high soil resistant or rocky place then you can consider an eathing enhancer just note that
most of the GEMS currently in the market are fakes / immitation. I spoke to the authorized distributor for GEMs and he said he doesn't stock them any more due to high dollar rates. Last one he sold went for 80k for 12.5kg bag.

Bentonite is a good alternative earth rod backfill but again I am not sure on the quality product we have in the market.

Bentonite also tend to expand and crack when dry this allows air bubbles which means some part of your earth rod losses contact with the earth if encased in bentonite.

Most people in the west just put the ground rod directly into the ground (without digging a hole) The idea is digging a hole reduces the compactness of the soil, a soil disturbed and backfilled might take 20 years to compact again. Soil compactness is required to ensure the rod maintains contact with the soil around it and contact is not lost if the soil settles.

I go with the school of thought that believe that if you can drive a long enough earth rod like 8ft and above you should be fine without any extra hole digging.

Source https://www.eng-tips.com/viewthread.cfm?qid=11731

When considered the minimum recommended earth resistance is sub 100ohms having a good earthing becomes quite inexpensive and easy to do without delving into sneak oil or spending tons of money.

Earthing is just one part of protection system. You still need to ensure earth neutral bonding is available in your system (by doing an impudence test) hopefully earthing of your grid transformer is done properly.

And if you are on inverter ensure your inverter has a MEN rely when operating in island mode.

Also your RCD.. if you get a lot of nuisance trip consider a 300mA RCD for the whole house just make sure the trip time is below 50ms.

Also take time to identify why your RCD is tripping.

This is my humble take on this. Remember I am not a qualified electrician so please feel free to take whatever I say with a pinch of salt.

NpvnStar:


TND is not a Brand name oo, it's the approved model number code in China to track between single phase and 3 phase servo stabilizers.

Just like SVC and all that naming system.

bigrovar:
I would be more concerned about 40v showing up on neutral that is not suppose to happen. Hiding the fault by shunting it to lower than recommended resistence earth rod should not be the solution. 40v is now going to earth.

I personally would be more concerned by 40v on neutral. I don't know much about this installation having a low resistance works then fine. Have you tried installing an ELCB just to rule out leakage to earth?

My focus is on resistential systems not factories or industrial applications. (I stated same in my post)

My post is mainly based on UK code which is what Nigeria is modeled after.

idsolar:


Wow nepa 119v. Like what I got on one site here in KD. Infact I was getting 110, 108v. Site steady on 220v now. Na servo boost am o. Jordy-ele servo, na Zeestone run am

FEGEITOK:
I traveled for 3 weeks.

I just returned.

I left my inverters hooked to my solar panels.

One was connected to utility power.

The other inverter was not connected.

I reduced the loads such that even if the sun was not generating enough PV power the batteries would not run out.

Would you have done what I had done or would you have powered down your unit or units?

I came back to meet everything as I left them.

I'd love your responses with reasons.

And by the way the panels are earthed and every earth is connected to or bonded to each other to be safe.