Axpert invertors

[savage]

My house is so energy efficient now that i wanted to use the existing EL behind the Axpert, and slap the 32A in before the Axpert between it and Eskom, since the Axpert is grounded to the Earth on the panel too. (Reason, should I have a short somewhere , the EL does disconnect and the axpert takes over on battery power, could be quite expensive error there.)

Here we go again...

A BREAKER will trip when there is a SHORT, a EARTH LEAKAGE will trip when there's an Earth Leakage - those are two fundamentally different error conditions.
You will need to have double pole BREAKERS on your supply, and load through the Inverter
Your Neutral BEHIND the Inverter, MUST be bonded to ground. If your supply is connected behind your Earth Leakage, your Earth Leakage WILL trip as soon as the inverter operates in bypass mode.

 

[savage]

I see my earth bar has only 3 terminals and they look pretty full. So can one just add another earth bar and tie them together or extend that one? Do they have to be next to each other? I know you are not supposed to share neutral terminals, is there a rule like that for the earths too? I hope not. I guess I have to search the SANS doc again. ):

You can install another one, anywhere. Just keep to the color standard. In terms of bonding the two earth bus bars (and bonding earth to neutral), use FAT cable... > 10mm2. Frankly, your mains supply looks like 16mm2 cable, so I'd suggest at least a 10mm2 to bond Earths & Neutrals to Earth in order to ensure you can carry your maximum capacity on the cables.

There is also only one neutral bar. I guess I will need two more, one between main supply, E/L, geyser and the breaker for the inverter. And then another neutral bar for the inverter load side. My current thinking is to just put all of it behind an E/L that also have overload. So can one add one on the left of the mains switch and one on the right side? And can one just drill and tap holes for them? I have seen that one can get ones that clip in, but that would use valuable breaker space.

For reasons I have discussed plenty of times before - do NOT put this inverter behind your E/L. A Breaker also have overload protection, and will trip when the rating of the breaker is exceeded (that is the function of a breaker). The Inverter must be on double poles, and your MUST bond the Earth and Neutrals BEHIND the inverter (load side). Because of that bonding, the Inverter cannot sit behind your earth leakage (unless you want your earth leakage tripping every time the unit is in bypass mode).

While looking I noticed that the neutral going from my E/L to the neutral bar do not have all its wires in the terminal. Oops, and it has been like that forever and everything except the geyser go through that.

That's very dangerous. You can have serious arching and over time, damaged insulation on the wires. It's imperative that all cables are terminates properly, and securely.

 

[savage]

I've found DC rated breakers so far at the following places:
1) acdc.co.za (Single and double pole but they are pricey)
2) suistainable.co.za (http://www.sustainable.co.za/catalogsearch/result/?q=circuit+breaker) the single pole ones aren't too bad but the double pole ones will set you back an arm and a leg, why are double pole DC breakers so disproportionately expensive, surely they should cost basically double what a single pole one does, what am I missing?

Can you please point out WHAT PRECISELY on there you think is a DC breaker? All I see at sustainable, is a bunch of AC Breakers, and a bunch of DC Fuses / Fuse Holders...

An AC breaker, on a DC cable, is pointless - it will NEVER trip / provide any kind of meaningful protection. You are much better off with a R25 fuse holder (which can open to act like a switch), and a R7 fuse.

 

[JohnHay]

For reasons I have discussed plenty of times before - do NOT put this inverter behind your E/L. A Breaker also have overload protection, and will trip when the rating of the breaker is exceeded (that is the function of a breaker). The Inverter must be on double poles, and your MUST bond the Earth and Neutrals BEHIND the inverter (load side). Because of that bonding, the Inverter cannot sit behind your earth leakage (unless you want your earth leakage tripping every time the unit is in bypass mode).

I think I did not express myself clearly. I meant everything behind the inverter, ie. lights and a few plugs, behind their own E/L that also have overload protection. So the inverter itself is not behind an E/L and its output will be bonded, like we figured out a few posts back. So I'll have a small DB close to the inverter and the inverter's output go through a double pole breaker there and then to the main DB where it goes into the E/L with overload and that feeds the alternate supply stuff. The small DB will also have a double breaker on the input side of the inverter.

That's very dangerous. You can have serious arching and over time, damaged insulation on the wires. It's imperative that all cables are terminates properly, and securely.

I agree that it is and I will rectify it today, when Eskom load shed. I will turn of the mains, but I just cannot get myself to cause my own load shed if I know they are going to do it at 12:00 in any case.

 

[savage]

I think I did not express myself clearly. I meant everything behind the inverter, ie. lights and a few plugs, behind their own E/L that also have overload protection. So the inverter itself is not behind an E/L and its output will be bonded, like we figured out a few posts back. So I'll have a small DB close to the inverter and the inverter's output go through a double pole breaker there and then to the main DB where it goes into the E/L with overload and that feeds the alternate supply stuff. The small DB will also have a double breaker on the input side of the inverter.



I agree that it is and I will rectify it today, when Eskom load shed. I will turn of the mains, but I just cannot get myself to cause my own load shed if I know they are going to do it at 12:00 in any case.

Please treat the power as live at all times. Don't 'presume' it's off, just because Eskom switched it off

Otherwise, all good I must have understood yes.

 

[mmacleod]

Can you please point out WHAT PRECISELY on there you think is a DC breaker? All I see at sustainable, is a bunch of AC Breakers, and a bunch of DC Fuses / Fuse Holders...

I remember finding DC rated ones on there a week or so ago (Guess I should have checked again before posting), can't see them now so either they were removed or some of those are dual rated I don't have time to look into the specs of each and every single one, so lets just assume they aren't, sorry people bad link my apologies.
ACDC does have however, not sure where else, perhaps you know some more places with DC breakers you would like to share?

An AC breaker, on a DC cable, is pointless - it will NEVER trip / provide any kind of meaningful protection. You are much better off with a R25 fuse holder (which can open to act like a switch), and a R7 fuse.

I just posted twice in a row warning people not to use AC breakers for DC (Unless they are dual rated) and now you proceed to lecture me about it as if I don't know this. Would it hurt you to not be completely condescending 100% of the time? Or to at least completely read what people post before lecturing them? It may not be your intention but the way you come across is as if you are more on here to belittle and insult people than to actually help half the time.

P.S. The above is not entirely accurate - to say that it will never trip - it may trip some of the time, the trip level may be different, it may arc across even when tripped/closed this may vary based on multiple conditions so it may not happen all the time, it will produce more heat and it may fail in very nasty ways like fusing closed completely.
This is actually far worse than never tripping, at least if it never trips you may pick that up when you test, if it sometimes trips you may do an initial test and think everything is okay when it is not.

 

[mmacleod]

http://cedsa.co.za/single-pole-dc-circuit-breaker-4
For the JHB people.. They only have up to 20a though.

 

[JohnHay]

Please treat the power as live at all times. Don't 'presume' it's off, just because Eskom switched it off

Thanks, I am a careful guy around electricity.

I fixed the neutral and while everything was off, checked that everything was screwed in tight. I found few that was very loose. It was a mission to fix the neutral because of the geyser breaker is very high on the left hand side. I'll check the terminals with my infrared thermometer when everything is working to make sure nothing gets hot.

 

[Marvo]

Can you please point out WHAT PRECISELY on there you think is a DC breaker? All I see at sustainable, is a bunch of AC Breakers, and a bunch of DC Fuses / Fuse Holders...

An AC breaker, on a DC cable, is pointless - it will NEVER trip / provide any kind of meaningful protection. You are much better off with a R25 fuse holder (which can open to act like a switch), and a R7 fuse.

There are some standard MCB's that are suitable for DC as well as AC protection although often the KA rating is derated due to the arcing problems when breaking a DC load so it's always wise to refer to the manufacturers data sheets.

Here's an ABB option that you should be able to find locally, there's also Merlin Gerin and several other possibilities.

 

[Vitamin_Sea]

So pretty much most of us had load shedding today... And this is true testament to the robustness of the Axpert. I had to make a Lasagne to take to the family gathering, and started about 45 min prior to the loadshedding knowing the "darkness" is looming...

so cooked the mince mushrooms bacon and made the sauce, and boom [ PEEEEEEEEEEEEEEP ] Eskom went down.

(Click on images to enlarge)

So I continued without a beat and fired up the oven:
[img=http://s4.postimg.org/z75q06lrt/20150628_085212_HDR.jpg]


Went over to the trusty Axpert and noticed a juicy 59-62 amps going into it to my own mini-grid in my house:
[img=http://s24.postimg.org/h2qaveobl/20150628_084959.jpg]


Lasagne cooking ( notice the battery shelf and yellow batteries in the reflection middle of screen next to fridge):
[img=http://s12.postimg.org/xfr4xg0sp/20150628_085229.jpg]


And all went without a Hickup :
[img=http://s2.postimg.org/ceym1jw9x/20150628_095917.jpg]




Will for sure put one on my boat as well once I rip out all the 120v US crap.

This monster machine has truly exceeded my expectations.

 

[savage]

House fire in Tableview area Saturday night. It is suspected that it was an electrical fault. So yes - these things happen, more often than you realise too.

 

[DollyAAAA]

Wow that's grim. Hope they're ok.

 

[DollyAAAA]

This device appears to be a transformerless design which makes use of MOSFETS - based on my research MOSFET based inverters (high frequency inverters) tend to have a lifespan of at least 3-5 years, whereas the transformer based inverters tend to have at least 10 years life span. The feature that sets this device (Axpert/MPP) apart from others, is the ability to view/control parameters via software. I have yet to come across a similar product having this feature and at this price range.

Also the transformer based design tends to be bulky, heavy and makes a buzzing noise (from my experience), not sure if all are that way. I presume the common Mecer UPS inverters are the transformer-based type, that is why alot of people say they are noisy and they are also bulky but apparently more resilient.

Just remember that if you are going to use this inverter as a UPS only, the inverter will actually not work all that much. In bypass mode it doesn't do anything except let the Eskom supply through. The inverter electronics only work when needed (in battery mode). So theoretically, it would last a LOT longer in this setup.

 

[Vetseun]

I had an axpert installed over the weekend (3kva 48v model). I have a couple of questions though and I thought I’d try and tap into the collective knowledge here. 

Firstly, the unit is currently basically set it automatic, but in my mind it’s worthwhile setting things like charging voltages etc… I’m not sure how much it’ll allow the batteries to discharge on auto. The manual documentation doesn’t specify that as far as I can see. Has anyone fiddled with this stuff on theirs? Worthwhile doing?

Secondly, the switchover isn’t quick enough to keep my PC and tv up. The electrician who installed it installed a separate physical relay that switches over to inverter when to power goes out. A small ups for the pc would solve that right? Basically using the UPS to bridge that small gap?

 

[DollyAAAA]

I had an axpert installed over the weekend (3kva 48v model). I have a couple of questions though and I thought I’d try and tap into the collective knowledge here. 

Firstly, the unit is currently basically set it automatic, but in my mind it’s worthwhile setting things like charging voltages etc… I’m not sure how much it’ll allow the batteries to discharge on auto. The manual documentation doesn’t specify that as far as I can see. Has anyone fiddled with this stuff on theirs? Worthwhile doing?

Secondly, the switchover isn’t quick enough to keep my PC and tv up. The electrician who installed it installed a separate physical relay that switches over to inverter when to power goes out. A small ups for the pc would solve that right? Basically using the UPS to bridge that small gap?

Not sure why your electrician installed that relay. The Axpert is supposed to do the switching, and it's plenty quick. My TV, decoder 2 PC's never misses a beat when switching over. All I see is a flicker in the house lights.

Check that your unit is set to "UPS" and not "Appliances". This will cause it to switch over faster (10ms vs. 20ms).

 

[Vetseun]

Just remember that if you are going to use this inverter as a UPS only, the inverter will actually not work all that much. In bypass mode it doesn't do anything except let the Eskom supply through. The inverter electronics only work when needed (in battery mode). So theoretically, it would last a LOT longer in this setup.

Quick question on the bolded part. My inverter is connected to to have everything except the geyser and stove connected to it. The thinking was that I can decide what to switch on or keep off during loadshedding. The electrician however said that the inverter (Axpert 3kva 48v) will however always be limited to output it’s rated wattage, even when on eskom. He claimed that when I’m on eskom and I decide to for example run the dryer or something and my usage goes above the 2,4kw that the inverter output is rated for the inverter will trip out (i.e. eskom is always going through the inverter power supplies)… To this end he installed a separate physical relay switch that automatically clicks over to inverter when the eskom supply drops.

Your statement above makes it seem that this is not the case?

 

[savage]

Not sure why your electrician installed that relay. The Axpert is supposed to do the switching, and it's plenty quick. My TV, decoder 2 PC's never misses a beat when switching over. All I see is a flicker in the house lights.

Check that your unit is set to "UPS" and not "Appliances". This will cause it to switch over faster (10ms vs. 20ms).

+1

No idea why the need for the relay is there. Something smells fishy with the electrician, and what has been done / configured.

 

[savage]

Quick question on the bolded part. My inverter is connected to to have everything except the geyser and stove connected to it. The thinking was that I can decide what to switch on or keep off during loadshedding. The electrician however said that the inverter (Axpert 3kva 48v) will however always be limited to output it’s rated wattage, even when on eskom. He claimed that when I’m on eskom and I decide to for example run the dryer or something and my usage goes above the 2,4kw that the inverter output is rated for the inverter will trip out (i.e. eskom is always going through the inverter power supplies)… To this end he installed a separate physical relay switch that automatically clicks over to inverter when the eskom supply drops.

Your statement above makes it seem that this is not the case?

What your electrician said is correct. The way that you insisted (apparently) on having it installed, is not correct. You can not (ever) have more than 3KW of power on the Inverter.

In the time that load shedding starts, to the time that you get to 'switch off' whatever you feel that is necessary, you would have already damaged the Inverter, assuming more than 3KW is connected. It's dangerous, in that you can (and will) damage your inverter this way.

Really not the correct way to go about this.

EDIT: SO not only have you NO idea on how much load is actually connected to the Inverter, as it is being bypassed by the relay (thus you can overload at any time without you even knowing it), but seeing as you have no idea of the load (in Watts), you also have no idea of how long your batteries will last in the event of load shedding...

 

[The_Traveller]

+1

No idea why the need for the relay is there. Something smells fishy with the electrician, and what has been done / configured.

Yeah this is a home electrician. Not one to install inverters.

 

[desiganp]

Whats the difference between the UPS vs Appliance mode in terms of operation of the Inverter?