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Thank you for the great forum, Safe Driving over the weekend. Sincerely Jason

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well, someone has to admit they are a newbie, let me be the 1st one, so no solar flares please - well not yet in any case.

we just built a home on the west coast, more like an industrial shed cladded with bricks - the end product looks like an 'ordinary' house; function before form is the motto.

on the roof are 8x300w renosol pvs and a 200l exstream solar geyser.
in the garage is an axpert 5kva inverter with four sonic agm 12v batteries.
i will get the geyser and stove point connected to eskom today, they were connected to the inverter [we are about to move in so no panic yet].
it is mostly my wife and i who will occupy the dwelling and i believe the top electricity huggers will be the washing machine, tumble dryer, toaster, iron kettle and microwave - i still do the dishes, it is good therapy and keeps me 'earthed' ;-)

that by way of introduction.

our aim is to minimize dependence on eskom - obviously - and to be prepared for power-cuts/tariff hikes which will strike sooner and later.
one question concerns the geyser connection, do i have it right? i reason that in the likely scenario where we have three cloudy days and the geyser's thermostat decides the unit needs electricity, consumption from the 4 batteries will soon be depleted and the load on the inverter will be too heavy.

would it be necessary to have some plugs/outlets in the house grid-coupled or will the inverter be able to 'sense' overloading and switch to the grid?

advice on the latter and any other tips will be much appreciated - and please keep it simple...

kind regards
yours in Christ Jesus
gabriel smit

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3 hours ago, gabriel said:

well, someone has to admit they are a newbie, let me be the 1st one, so no solar flares please - well not yet in any case.

Welcome! Must say, you have some guts with your avatar. Don't you know everyone on the internet is an atheist? :-P

(I'm kidding of course, I share your convictions :-) )

I would never put a geyser downstream of the inverter. Not a standard one anyway, and possibly none at all. If you have a grid connection, given that you are on the west coast, just leave it Eskom side. The stove is actually not a heavy consumer. Sure, it takes a lot of power WHEN IT IS IN USE, but it is in use only for relatively short periods, and even while it is in use, the actual usage in kwh is on the low side. I'd leave the stove Eskom side or switch to gas (gas is slightly more expensive than electricity, but so convenient and a good alternative if you want to be independent).

3 hours ago, gabriel said:

would it be necessary to have some plugs/outlets in the house grid-coupled

I believe it is good to have some way other than just the inverter to get a grid connection, but then I also believe a physical changeover/bypass switch is a must-have. If you have a changeover switch, then you can probably get away without dedicated grid outlets.

Speaking of that, the Victron inverters have a really nice feature that is often overlooked. The two sockets at the bottom of the inverter where the input and output plugs in has a male/female configuration that also plugs into each other. You can bypass the inverter by literally unplugging the inverter and plugging the two ends together. For a small cabin-type setup, that might be good enough, but for any larger setup where things are going into the DB, I'd go with a changeover switch.

invertor-Victron-MultiPlus-Compact-24-800-16-16-24V-16A-700W-220V-3.jpg

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Welcome to the forum Gabriel.

7 hours ago, gabriel said:

consumption from the 4 batteries will soon be depleted and the load on the inverter will be too heavy.

You have not specified the Ah of your batteries, but you are right. I would definitely connect the stove, oven and geyser directly to Eskom. 

7 hours ago, gabriel said:

would it be necessary to have some plugs/outlets in the house grid-coupled.

No, I don't think so. If you want to, you can have one plug in the kitchen wired directly to Eskom with the other high energy items mentioned above. You can then run the kettle, microwave, toaster and frying pan off that plug if you want to. Although the toaster, kettle and microwave all run for relative short periods of time and therefore should not be a problem if you want to leave them on the inverter. Just don't try and run them all at the same time.:)

The only other item that is a bit of a power huger is the tumble dryer. The element switches on and off during the drying cycle. The same with the iron, but that should be ok. The washing machine uses less power than you think and should not be a problem.  

Just get into the habit of doing the washing, tumble drying and ironing during the day when you have a lots of sunshine. When the sun sets, you sit back and watch TV with one or two lights on till you go to bed, using minimum grid power till the next day. 

 

7 hours ago, gabriel said:

or will the inverter be able to 'sense' overloading and switch to the grid?

Yes, the inverter will sense if the load is excessive and will switch to grid in the event that you overload it. 

As Plonkster said, a change over/bypass should be installed in case something goes wrong with your inverter. You then just flip the switch to bypass the inverter without having to rewire your DB Box. Also handy in the event you want to do some welding with a heavy duty welder or something similar. Flip the change over switch to bypass the inverter and all plugs will be running off Eskom power. Do what you need to do, then switch back and put the inverter back on line. 

58ca93b56641c_changeoverswitch.thumb.jpg.451fccd987bddc8d50d3b5c15b7119b6.jpg

 

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thanks for the welcome and valuable comments don and plonkster, and yes, re the avatar, He spilled His guts for me, this is the least I can do.

on the spot info regarding the change over from batteries to eskom [lets call a shovel a spade, 'grid', 'utility', 'mains', 'municipal power supply' etc are all monopolized by eskom and the denizens of nkandla] regarding this inverter was forthcoming from http://www.geewiz.co.za [option 23 must be set to enable].

i'll see what can be done re an eskom outlet in the kitchen and the 'scullery', sounds good, maybe something red to match my ferrari [just kidding of course].

the manual change over is a great idea, i presume don's image to be of one.

speaking of nkandla - are they off grid [or off topic...]?

i've browsed this forum and, apart from some of the 'geek-speak', i already feel at home!

yours in Christ
gabriel

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@gabriel I can see you fit spot-on in with this forum. 

I laughed at the tongue in cheek sideswipes at other topics. You obviously have seen how quickly we can get off-topic - after the question has been answered off course. :D:D:D

Looking forward to your posts. 

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Don's picture is of a 3-phase changeover I think, it looks like it's 4 spaces wide. Three phases and neutral. Hager makes a nice double pole one that's around R200 and works well. Acdc sells a 3-phase (no neutral, star setup iow) one for under R200, but in my experience it's somewhat rubbish. I threw mine out and replaced it with a Hager.

Sent from my GT-I9195 using Tapatalk

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48 minutes ago, plonkster said:

Don's picture is of a 3-phase changeover I think

No it is a single phase 4 pole. I connected Live and Neutral from the Inverter to the No.1 Position (Upward Position). Center Position is off - nothing connected. Then I connected the Grid Live and Neutral to the No. 2 position (Pushing the level downward).

In the upward position, power going to DB Box comes from inverter.

Center position - No power to the DB Box.

Downward position, power going to DB Box comes from the Grid (Inverters Bypassed)  

I have 2 of these change over switches installed. These change over switches are designed as change over between Grid and Generator. The "G" refers to "Generator". 

The first one I installed is a change over switch between Grid and Generator.

L - Live from Grid

G1 - Live from Generator

N - Neutral from Grid

GN - Neutral from Generator

The second one is to Bypass the Inverters. Here I switched the Grid position which is normally position No.1 with the Inverters and put the Grid on position No. 2. as explained above. The only reason I did that was that the Inverters would normally power the DB Box and I therefore wanted it in the upward position. I don't want to look at the DB Box and one of the switches are in the downward position or as we normally see it as the "Off" position. 

 

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herewith an update:

one double eskom outlet in the kitchen has been installed and one double eskom in the garage, the tumble dryer has been moved into the garage where it will have a platform to make it eye-level. for the future use of heavy duty electricity huggers like welders and concrete breakers we now have facilities.

the geyser and stove point are also on eskom.

there was a change over switch which i did not recognize [i told you i'm a newbie!]

thank you don for the settings, i'll investigate after lunch.

in Christ

gabriel

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On 3/16/2017 at 3:06 PM, Don said:

58ca93b56641c_changeoverswitch.thumb.jpg.451fccd987bddc8d50d3b5c15b7119b6.jpg

 

I also have one of those now connected 63a rating. Feels alot better quality that the AC DC ones that I got in the beginning. The connectors is also quite nice to work with. 

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hi

thanks for all your inputs!

tomorrow i will set the axpert to:

1-sol
2-30a [already done]
3-apl
4-sds
5-agm
6-ltd
7-ttd
9-50hz
11-30a
12-48v
13-56v
16- cso in winter change to snu
18-alarm off
19-fep
23-bye
26-56.4v
27-54v
29-42v 47


i have been advised to get the bmv 702 - anyone out there who knows where and approx cost?

in Christ

gabriel

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browsing the forum it has become apparent i will have to invest in the bmv702. would that make an icc superfluous or would they be complimentary, and if not so, would it be necessary to get an icc?

have a sunny sunday!

in Christ

gabriel

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9 hours ago, gabriel said:

browsing the forum it has become apparent i will have to invest in the bmv702

Without it, you are really in the dark and guessing the State of Charge of your batteries. Using WatchPower to determine your battery capacity is like asking a stranger to give you a number between 0-100. Have a look at the graph below.

The Accurate State of Charge of the Batteries is the blue line coming from the BMV-702. The red and green lines are the Battery Capacity as reported by the inverter and the value you would see in WatchPower.  You decide for yourself.

soc.thumb.JPG.00747baa22084722ef166d12925a82fc.JPG

 

9 hours ago, gabriel said:

would it be necessary to get an icc?

Once you have used it, you cannot get along without it. 

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4 minutes ago, SilverNodashi said:

The ICC downloads don't work anymore.

They work for me. I downloaded ICC for Pi yesterday and just downloaded ICC for Windows just for fun now.

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