₦airaland Forum

NiyiOmoIyunade:
Well ...... there should not .....

But I think if you are paranoid, or want to go overboard with your protections....

Please let me defer to core power experts like Oga Pranil to talk about this one please - whether or not one still needs an SPD given sufficient earthing/grounding in place.

NiyiOmoIyunade:
No boss.

Ogas Barezzi and Pranil have said it all. You cannot use an MCB to protect equipment - they exist to protect your wiring from overcurrent situations that could cause the wires to run hot, melt the insulation and cause a fire. They also reinforced that this particular MCB you had in the picture is not even DC rated hence unsuitable for use anywhere between your panels and batteries.

To protect from lightening do the following.

1) Install an external earthing/grounding point in your premises - connect the earth/ground side of all your AC equipment, earth/ground point (terminal or chassis) of CC and panels and negative post of batteries or battery bus bar (if paranoid) to this common building earth/ground point.

2) Install a lightening arrestor on your roof and connect this also to the common external ground/earth point for your premises

3) Optionally, Install a surge arrestor e.g the Midnite MNSPD 300 to further protect AC and DC components. Midnite has different ones for each application.

The common earth point in your premises will provide a safe path for all surge currents to be diverted to the ground.

The lightening arrestor on your roof represents an 'attractive spot' for lightening to hit and from there be diverted safely to ground.

NEC code is to have only one external earth/ground point per premises to prevent surge current arcing between earth/ground points and electrocuting people in between the current flow path.

seyitanhep1:
Happy Birthday to Jamzig, One time PRO...

The OP of this thread

RCDIY:
Mail sent.

Thank you

dapsyra:
For longevity, safety and extreme temperature (-20 to 55 deg Celcius), Lithium Titanate Oxide (LTO) battery is the best of the Lithium battery family.

With cycle life >10,000cycles at 80% DOD, they can be fast charged from 0-90% in less than 10 minutes at 10C without thermal runaway. The only down side is that they are quite expensive.

I have somethings off my sleeves concerning LTO batteries. I might have limited quantity to sale soon, being leftovers from a classified project.

Please stay tuned on this channel for the announcement in Jan/Feb, 2018

collinslevi:
Plsss is anyone having issues opening a diamond yellow account?

pranil:
Nope has a password lock

But it is just an 3 pin plug so can be easily removed and plug directly inserted into the socket . But makes a nice loud alarm sound once the load goes above alarm value before tripping the output if the trip threshold is met ( has time to avoid peak spurious triipngs)

I even asked the company if they will make a wired version but no plans yet

if you have money to spend and don't mind tinkering the smart sockets like TPlink and Samsung smart things also have a power threshold alarm and a notification on the phone ( need full time wifi though in house)

pranil:
for a single socket, I use this -

https://www.aliexpress.com/item/PR10-F-BS-13A-power-metering-socekt-kwh-meter-0-1-3250w-watt-meter-power-recorder/32697027826.html?
It has setpoints for power and current both activated independently with timer to prevent abuse
I mainly use it to stop my Inverter AC being used in turbo mode ( in turbo they draw 2.6 KW as against 700 watt of normal mode)

for the whole circuit at the output of inverter or DB USe an overcurrent relay wired to the AC contactor or a built-in unit

https://www.aliexpress.com/item/High-quality-current-limiter-lirait-appliances-0-5A-32A-tutamen-control-switch-demand-limiter-free-shipping/32417613258.html?

https://www.ev-power.eu/Measure-Test-Tools-1-1/Current-Monitoring-Relay-PRI-52-AC-0-5A-25A-CE.html

NiyiOmoIyunade:
Amps can never be taken in isolation but rather you must ask the question "at what voltage" and are these AC amps or DC amps? Then you convert the amps to watts so you have a constant base to work off

My laptop power supply reads
INPUT > 100-240v~1.5A
OUTPUT > 20v~4.5A

The INPUT ratings are AC ratings and equipment manufacturers are required to list the MAX amperage the equipment will draw under load - in this case it is 100volts * 1.5Amps = 150watts

The OUTPUT side is a DC reading so 20volts * 4.5Amps = 90watts.

I can relate 150watts max power draw on the AC side to a 90watts DC output - a tad inefficient but plausible given the operational constraints with such a wide input voltage range.

In my case I would go with the AC side/INPUT load of 150watt because that is the load your laptop power supply would present to your inverter or PHCN or Generator - so size your load limiting breaker accordingly bearing in mind the rules I earlier stated - a 240v~1amp AC breaker is rated to carry a roughly 240watt load indefinitely without tripping

NiyiOmoIyunade:
A 1Amp AC Breaker or Fuse would work BUT 1 AC Amp is approximately 240watts and therein lies the problem - a 1Amp breaker is rated to carry a 1Amp/240Watt load indefinitely without stress - it would only trip at best at 2 to 3 times its rated capacity e.g if you plugged an iron or heating element. So with a 1Amp breaker, you would have exceeded your target load limit of 100w several times before it would trip.

So you need like a 0.5Amp AC breaker which would be rated around 120watts which is closer to the load limit you want to impose.

AC Breaker is prefered over a fuse because you can reset and reuse it several times whereas a fuse is single use, once it opens/burns you need to put in a replacement - which bring another problem! Location!!! You want to place the breaker in a place where you can easily reset it as you don't want to be opening up your AC Panel/Distribution Board anytime you wanna reset the breaker so you place it in a easy to access place

A smart kid or other member of your household would quickly know "where Daddy presses to reset the breaker" and its only a matter of time before they figure out how to bypass it or hurt themselves while playing with it!!!

In the end breakers and fuses were designed to protect your WIRES/CABLES and not equipment/loads - they would only trip/open minimum around 2 to 3 times their rated capacity. . GFCI type breakers are designed to protect people but I don't see how you can use them in this load limiting scenario.

If you can lay hands on a 'type B' AC breaker for this current limiting exercise then all the better I would say.

kiekie1:
Hello, try using the AC breaker as an overload trigger for that particular socket and u must manually reset .. Cheer's

kiekie1:
I guess he was speaking of low quality Chinese batteries or rebranded battery versions . Richmond sent pics of few jobs he cleaned up some months ago and we still see so many funny installers roaming the streets of Lagos as a case study . I have so many electricians in my hood admiring solar jobs and trying to learn intricacies in inverter - solar installation the wrong way tho !

Dam5reey:
It's simple... You can't wire DC bulbs in a duplex with about 60 light points...

How do you want to run DC supply to 3 TVs in different rooms if you use decoder

Inverter self consumption is negligible...

I have done this practically.. My phone consumes the same power using Normal AC adapter VS DC-DC converter.. so what's the point

bigrovar:
One of the things I learned while cutting my teeth as a sysadmin is the kiss principle. Keep It Simple Stupid. Same thing applies to offgrid solar. What you are proposing is very complicated and frankly is more hassle with a negative net benefit overall. The problem with low wattage device is they are also low voltage, which means even if a 12v leave the battery before it gets to the led bulb its has lost some voltages to resistance so only about 10 or 11v gets to the led. add that to the issues of fusing and breakers and how much of a mess your connection would be. Then there is the issue of using dc to dc converters which will still lead to conversion loss u were running from...

Inverters are not has bad as u are making, there are units which are 95% efficient and would serve just fine. when u compare the amount of money spent and watts lost to resistance. the former is a better option.

bigrovar:
We have discussed this before: It sounds good on paper but its not practical. DC are low voltage high current devices which means they are prone to voltage loss when transferring high current over a distance ( Ohms law) You would require your house to be wired with very large cables which are just not practical and also very very expensive (money which could be used in buying more battery/solar panels) also DC only house would force you to stick to 12v system which can be very limited and inefficient when you scale most dc appliances have different voltage ratings, from 6v (for clippers, mobile phones etc) to 18v for laptops and 12v for some of the rest. This means you would still need a dc to dc converter hence the conversion loss you are running from would still hit you. Then you have to consider the cost of maintaining the dc appliances. How many people do you reckon can fix a dc fridge, refrigerator, TV.. think of the parts. and consider the high cost of DC appliance (a dc freezer is almost 50% more expensive than its AC equivalent) when you consider all this you will note that what you are proposing will only work for a limited small scale application (like a small barber shop or small offgrid system less than 500w in size) it makes no sense for a large general house hold use

pranil:
Main loads are heating and cooling loads - You do not want 35 mm2 cables connecting your water heater and air conditioners. ( say 24 or 48 V) at the same time higher DC voltage is equally dangerous ( 500 V DC) and much harder to stepdown economically.

residences started as DC supply in US ( Edison company - now GE) before overtaken by AC ( TESLA - Westinghouse )

For the electrical engineers, Tesla versus Edison( war of Currents) is an interesting piece of history. Edison famously used to kill cats and dogs publically using Ac supply proclaiming AC was dangerous than DC ( of course DC was unearthed)

http://mentalfloss.com/article/30140/acdc-tesla%E2%80%93edison-feud

JUO:
Solar/AC/DC ceiling fan is available
Functions: remote control, led light, regulator, maximum power 30w, AC input adapter 220v, DC input 12v, solar input 12v. Size 56'.etc
Price 23k, 25k for a piece

Minimum order is 2pcs

phrezzz:
. Send me your mail

abisolaarshow:
Locartion: surulere, lagos

Mukah1234:
Can you please give me a breakdown of all sizes and their prices supposing i'm going for 300 pieces for a start.

chris81964:
Send an email to anwokolo@atlanticwastepower.com. Tell her I asked you call and ask her to follow up with HR

chris81964:
You are most welcome. Thank you for watching

chris81964:
It came up in our morning meeting today. The technical team lead had suggested it. I told him to communicate with HR and we will follow directives from HR.
Apologies if you did not get a response. We have been a bit overwhelmed by job applications

chris81964:
Good Morning Folks,

I hope my message meets you well. Please if you paid someone else to install your solar power for you, don't ask me for advice on fixing it. We charge a fee to diagnose problems on bad installations.

If you are a DIY'er I am very happy to answer questions and offer advice.

There is a clear difference between the two. I do solar for a living and if you are willing to patrnonize someone other than me it is your right. However if you want a performance problem diagnosed it is a minimum of N7500. And if it is an unusually bad job that fee is double