Getafixx
Active Member
If you don't want to DIY you can get a DIN mounted indicator light from ACDC part GW96584 for R180. Just phone in advance because they may have to order from the warehouse.
-
Join the MyBroadband community
South Africa’s biggest forum. Discuss, discover, and connect with thousands of members.
-
Question of the Day: If you were buying a TV today, which brand would you choose?
Axpert invertors
- Thread starter Draganchor
- Start date
If you don't want to DIY you can get a DIN mounted indicator light from ACDC part GW96584 for R180. Just phone in advance because they may have to order from the warehouse.
quinn_the_eskimo
New Member
- Joined
- Feb 23, 2015
- Messages
- 8
- Reaction score
- 0
Excellent. Thank you for that.
hi
got the following quote on an axpert inverter
1*5kva Axpert hybrid uninterruptable power supply with built in mppt solar charger
4*raylite 95Ah deep cycle batteries in battery box
2*double pole isolators plus wiring
1*installation to the db board of house
R22k
My needs are just to cover us for load shedding for the meantime - run pc,tv,lights,decoder etc.
Perhaps to add solar panels in future to bring down eskom consumption
Anyone care to comment?
Is there anything I should add that would be needed?
Are the batteries appropriate or should i get bigger/better?
Thanks
got the following quote on an axpert inverter
1*5kva Axpert hybrid uninterruptable power supply with built in mppt solar charger
4*raylite 95Ah deep cycle batteries in battery box
2*double pole isolators plus wiring
1*installation to the db board of house
R22k
My needs are just to cover us for load shedding for the meantime - run pc,tv,lights,decoder etc.
Perhaps to add solar panels in future to bring down eskom consumption
Anyone care to comment?
Is there anything I should add that would be needed?
Are the batteries appropriate or should i get bigger/better?
Thanks
dunkyd
Executive Member
For your immediate needs, 4 k for an inverter with charger and a battery ?
Deckert
Well-Known Member
Well, let's break it down. All pricing I show includes VAT.
The 5kVA inverter (at cost, from Rectron) is about R11k. Fairly good quality 100Ah batteries (also from Rectron) are about R7000 for four. So that leaves you with about R6000 for the switches and the labour. Since the switches are about R150 each, his labour and his margin on the kit comes out to R5700.
I have no idea as to the extent of the re-wiring that has to take place, but the above should give you a good indication as to whether it is a good deal or not.
Just some further observations from me:
- 100Ah batteries give you:
+ 76 minutes at 3kVA load (fully discharged)
+ 268 minutes at 1kVA load (fully discharged)
I'd say that you should reckon on about half of the above times for a 50% discharge of the batteries. I wouldn't use such small capacity batteries with a 5kVA inverter - you may as well then rather go for the 3kVA (with the obvious PV solar panel limit that comes with it). It all depends on your usage patterns.
- is he only installing the two switches? what about:
+ DC protection and fuses
+ earth leakage protection
+ indicator warning lights, etc?
--deckert
Also electromechanica sell a Hagar code SVN122 (red) for R130.00 list price.
Sounds like a pretty good price to me.
To compare:
RCT Axpert 5000VA inverter + 4x Deltec 102Ah 12v battery batteries - R 18,855
2x Double Pole Isolators - R182
Additionally what is required but not quoted:
1x Circuit breaker from Main switch to inverter
Additionally I would have added the following:
2x Surge protectors (one before one after) - R356
I would also put the Inverter on a RCD - R213
The RCD (in SA more commonly known as Earth Leakage) makes it safer so that you don't get electrocuted in case of accidentally touching.
You also, legally, may not wire the inverter to normal plugs without the RCD. If you don't have an RCD you MUST use these plugs/sockets.
Additionally you would need 2 meter of 50mm cable (±R75 per meter) and 4mm twin and earth (2.5mm can be used but I would go with 4mm personally). The twin and earth needs to run to the inverter and back to the breaker box (2 runs)
Lastly, you need 50mm crimps (±R15 each) and a 100 amp fuse (± R200).
Overall R22k is a good price imo when you include labour. Depends if he does everything correctly however. I wouldn't do it for less than R2k in labour personally (Not that I do this as a job but still).
My 2c.
Last edited:
DollyAAAA
Well-Known Member
You mean house wire (7-strand) or solid core, as in twin & earth? NOT flex. AFAIK you may only use solid core or house wire in a fixed LV AC installation. Flex generally refers to finely stranded wire.
LOL, yep, I don't know why my brain does that. It is flat twin and earth I was referring to
Typically solid core although it seems that Voltex sells the 4mm and up with stranded solid cores in the flat twin + earth configuration.Fixed my post above.
EDIT: DollyAAAA any idea of places that sell 8mm and 10mm wire in meters? The solid cores combined to make 8/10mm like that used in a DB box?
Last edited:
DollyAAAA
Well-Known Member
LOL, yep, I don't know why my brain does that. It is flat twin and earth I was referring to
Fixed my post above.
EDIT: DollyAAAA any idea of places that sell 8mm and 10mm wire in meters? The solid cores combined to make 8/10mm like that used in a DB box?
I know a place in Montague Gardens by the name of GFP Electrical, I have bought some wire by the metre there before. Not sure about 6/8mm though. You can also try Transform Electrical.
[email protected]
Member
- Joined
- Aug 12, 2015
- Messages
- 11
- Reaction score
- 0
Hi All
New here. I have read through all of the threads pertaining to Axpert inverters. Wow very interesting reading. I am currently installing my system and there are still some answers that are eluding me.
Current home setup
Solar geysers. Hardly ever switch on using Eskom.
Cook on gas.
95% of my lights are LED. The rest are energy savers which I have not changed yet
Monitoring & stats
Using efergy monitor
Watts displayed average sits between 300 to 800 watts. Only goes up higher when large appliances are used e.g. Oven/geysers
Calculated my usage @9kw/h/days. This without the solar system I am busy installing.
Solar setup
Axpert 4kw 5kva
4 x 250 watt panels
4 x 105ah batteries. Gel
Separate DB for solar.
All lights will be on solar and a few selected plugs. These plugs have a normal and a clean line plug.
I am currently about 70% complete with my installation.
So here are the questions. I will answer them myself to see if I get it right or wrong
1) how do I bond the inverter AC OUTPUT neutral to earth.
So what I have read so far is that I bridge the neutral and earth from the inverter ac output. The ac earth output then get earthed to my isolated solar system DB which is then wired to a earth spike outside. I can do the bridge either by the actual outputs of the inverter or bridge the earth bar to the neutral bar in solar system DB. Which one is better?
2) I have heard of a bonding block and also heard of the negative of the battery bank being earthed. Can anybody explain this to me?
3) PV panels have male female connectors for connecting in series. From the Axpert manual you can only connect so many in series. So if I understand it correctly I have to connect all 4 in parallel. If so are there connectors that allow your join them or do you cut the connectors off to connect in parallel.
4) The PV panels are also required to be earthed to a earth spike. Should this be a separate earth spike or can I run it to the same spike as mentioned above.
5) EL is not required if you using clean power plugs ie the red sockets with half earth. I assume this is because the wiring for these plugs will be completely isolated from the houses current wiring and connected straight to the solar panel DB including the earth of course.
I cannot think of any other questions at this moment. Here are some pics of my current progress
Current DB https://www.dropbox.com/s/j2ughxqp7illgln/photo%202015-08-09%2C%2017%2057%2032.jpg?dl=0
Solar DB https://www.dropbox.com/s/fhosa40auew77jp/photo%202015-08-10%2C%2011%2057%2048.jpg?dl=0
Path from current DB to isolated solar DB. https://www.dropbox.com/s/iackwp4xdx0d2id/photo%202015-07-11%2C%204%2037%2058%20pm.jpg?dl=0
Check this and let's see if you can figure out what is this. This is my prototype which I have tested so far.
https://www.dropbox.com/s/99ypuquknhq1ac7/photo%202015-07-16%2C%2020%2013%2033.jpg?dl=0
I hope you guys will be able to help me. Actually I believe you will hehehe. Most electricians that I have asked these questions are clueless. Thanks in advance
New here. I have read through all of the threads pertaining to Axpert inverters. Wow very interesting reading. I am currently installing my system and there are still some answers that are eluding me.
Current home setup
Solar geysers. Hardly ever switch on using Eskom.
Cook on gas.
95% of my lights are LED. The rest are energy savers which I have not changed yet
Monitoring & stats
Using efergy monitor
Watts displayed average sits between 300 to 800 watts. Only goes up higher when large appliances are used e.g. Oven/geysers
Calculated my usage @9kw/h/days. This without the solar system I am busy installing.
Solar setup
Axpert 4kw 5kva
4 x 250 watt panels
4 x 105ah batteries. Gel
Separate DB for solar.
All lights will be on solar and a few selected plugs. These plugs have a normal and a clean line plug.
I am currently about 70% complete with my installation.
So here are the questions. I will answer them myself to see if I get it right or wrong
1) how do I bond the inverter AC OUTPUT neutral to earth.
So what I have read so far is that I bridge the neutral and earth from the inverter ac output. The ac earth output then get earthed to my isolated solar system DB which is then wired to a earth spike outside. I can do the bridge either by the actual outputs of the inverter or bridge the earth bar to the neutral bar in solar system DB. Which one is better?
2) I have heard of a bonding block and also heard of the negative of the battery bank being earthed. Can anybody explain this to me?
3) PV panels have male female connectors for connecting in series. From the Axpert manual you can only connect so many in series. So if I understand it correctly I have to connect all 4 in parallel. If so are there connectors that allow your join them or do you cut the connectors off to connect in parallel.
4) The PV panels are also required to be earthed to a earth spike. Should this be a separate earth spike or can I run it to the same spike as mentioned above.
5) EL is not required if you using clean power plugs ie the red sockets with half earth. I assume this is because the wiring for these plugs will be completely isolated from the houses current wiring and connected straight to the solar panel DB including the earth of course.
I cannot think of any other questions at this moment. Here are some pics of my current progress
Current DB https://www.dropbox.com/s/j2ughxqp7illgln/photo%202015-08-09%2C%2017%2057%2032.jpg?dl=0
Solar DB https://www.dropbox.com/s/fhosa40auew77jp/photo%202015-08-10%2C%2011%2057%2048.jpg?dl=0
Path from current DB to isolated solar DB. https://www.dropbox.com/s/iackwp4xdx0d2id/photo%202015-07-11%2C%204%2037%2058%20pm.jpg?dl=0
Check this and let's see if you can figure out what is this. This is my prototype which I have tested so far.
https://www.dropbox.com/s/99ypuquknhq1ac7/photo%202015-07-16%2C%2020%2013%2033.jpg?dl=0
I hope you guys will be able to help me. Actually I believe you will hehehe. Most electricians that I have asked these questions are clueless. Thanks in advance
You are mixing concepts here.
Earth spike is something to worry about separately to the rest of your install.
I think you should definitely get an electrician in that actually understands these concepts.
But if I understand the SANS docs correctly, that is supposed to happen at the main DB board. eg. earth spike is connected at the main DB earthing bar.
But I'm not telling you to do this and advice you seek the help of an electrician when doing that.
As for the bonding of inverter neutral and earth:
I remember that being mentioned earlier in this thread. Thinking about it again now I would be cautious about that.
Your Axpert should have input power from Eskom and then an output connector which is either Eskom or Inverter depending if the power is on or off.
The output connector that is either Eskom or Inverter should definitely NOT be bonding earth and neutral.
Nor should you connect your Eskom neutral and earth.
The reason it is a stupid idea is because while on Eskom power you are creating an earth connection that runs VIA your Inverter.
Internally the Axpert inverter should have the neutral and earth bonded before the change over relay. (eg. they should be bonding their inverter earth and neutral)
But then again, they may use a center tapped design in which case it would be dangerous to bond neutral and earth
Reasons center tapped would be dangerous to bond:
Neutral will have an elevated voltage relative to earth. By bonding you are raising every single earthed metal surface in your home's potential (this would include pipes used by your water. Yummy yummy electrocution when you shower, hmmm).
This can be tested simply:
When Axpert inverter is running (not plugged into Eskom power)
What is the Live to Neutral voltage? (Should be 230v)
What is the Live to Earth voltage? (Should be 230v, not 120v)
What is the Neutral to Earth voltage? (Should be 0 volts or close to it, 120v is bad)
Legally you cannot use an inverter that is center tapped. But if you are, for the love of good things do not bond neutral and earth. That is making it less safe, not more safe.
I don't really see the point of this unless you plan on running DC all around your house. The idea is to give the current a place to go in case of accidental contact with a live conductor. Additionally if your battery bank were to have elevated potential it would make it "safer". But if, like some cheap inverters, your battery bank voltage is elevated during operation, connecting your battery negative to earth will end badly.
I admit I don't know anything about PV panels, maybe someone else can comment
Earth to your house earth. That is, an earth wire that goes to your main DB earth.
Dedicated, not clean power.
No it is not because it is isolated. It is because they are red and you are hoping that someone realizes that means not to F#@k with them or they will die and only plug things in there that are intended for the dedicated supply.
These days people just create multi-adapters with dedicated plugs, so IMO, defeats the purpose.
My opinion: Use dedicated sockets but put them on an EL anyway for safety. EL costs R200, do you REALLY need to save R200?
Last edited:
But if they did that, it would limit the installation options to always be before a E/L device and never behind it. Maybe they did not want to limit your options?
Do you think the earth voltage will be raised? Maybe if the earth wiring is thin. I would have thought that it would just create huge overload for the device and it would let its smoke out?
This test will work ok for transformer based devices, but not so good for electronic inverters that use FETs or IGBTs for the output stage. For instance if I do not tie neutral to earth on the output on my Infinisolar, its neutral would slowly drift away from 0V, but even just connecting a resistor between earth and neutral would bring the neutral back to 0V and the resistor do not heat up, so there isn't much current flowing, if at all.
On the phone so short reply:
In a typical residential installation earthing is at the point of supply . Where the neutral and earth is "split"'ie separate wire read up on TNS or TNC-S earthing of low voltage networks.
You should not connect earth and neutral at the inverter input. If it's fed from a E/L it will trip. If not you are sitting with a incorrect earthing system
I believe that the input and outputs of the Axpert inverter are Galvanicly isolated. So in theory the output neutral can be tied to earth to ensure its not floating. An E/L should then be installed before feeding other circuits .
In a typical residential installation earthing is at the point of supply . Where the neutral and earth is "split"'ie separate wire read up on TNS or TNC-S earthing of low voltage networks.
You should not connect earth and neutral at the inverter input. If it's fed from a E/L it will trip. If not you are sitting with a incorrect earthing system
I believe that the input and outputs of the Axpert inverter are Galvanicly isolated. So in theory the output neutral can be tied to earth to ensure its not floating. An E/L should then be installed before feeding other circuits .
Not true.
This is the configuration in a UPS (backup/line interactive) or Inverter with change over.
Input power/Utility (or Eskom in SA) goes into a change over relay which is 2 pole double throw.
The relay has 4 inputs (2 poles = 4 inputs) and 2 outputs (common terminal)
When utility is on, the relay is simply connecting the utility power (2 poles) with common (2 poles).
When utility is off, the relay is connecting the internal inverter power (2 poles) with common (2 poles).
So connecting the common terminal neutral and ground is bad. As you say, this would create a neutral fault when you are on utility power.
This would also mean that you create a bonding at your inverter between neutral and earth for utility which is horrible bad idea.
However, if the inverter neutral and earth are bonded BEFORE the relay, then you effectively have a earth bonding that is only bonded when you are on inverter power.
Hope this makes sense.
That is the correct way to do it, but, again, it is not safe if the inverter is center tapped.
If the neutral is not at the same potential as earth, then yes, you can have an earth that is at a raised potential.
With an earth spike I am curious how this would turn out.
Either way, I wouldn't, ever, connect a neutral and earth if the following isn't true:
Live -> Earth (230v)
Neutral -> Earth (Near 0v, nowhere near 120v)
Well the only reason an inverter would not bond neutral and earth internally is due to design... eg. Neutral not at the same potential as earth
But yeah, you make a good point, a simple test is:
Put a incandescent light bulb between inverter neutral and earth and see if it lights up. Pretty damn safe test and if it lights up even a bit then you have your answer...
Not really no. This is a picture of the PIP 4048, which looks like what I saw for the Axpert (shows the internals better than most other pics posted).
The mains comes in, then goes to those relays at the bottom right where it is either directly output or it switches to inverter power.
The transformer seen on the other side of the board (which is what you need to galvanicly isolate) is a high frequency transformer driven by mosfets.
This picture allows you to see the relays at the bottom right more clearly.
Obviously, the simplest way to test this is to test for continuity between the two.
So place a test lead from a tester on the neutral input and neutral output while on utility, if there is continuity then there is no isolation (which is what I expect).
EDIT: Interesting, they actually use 40amp SPNO relays x4. Explains why the change-over time is adjustable. Either way, they are simply switching using relays with no isolation.
Last edited:
Dimpie (JIGSAW)
Honorary Master
I'm sure wstevens is now even more confused 