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Godoh
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Joined: 26/09/2020
Location: Australia
Posts: 455

Posted: 07:14am 04 Sep 2024

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I wrote to Latronics inverters recently and asked them if their LS inverter ( transformer based) would be OK with a GTI AC coupled to it.
The response was that they did not recommend it as the inverters had no protection for AC feedback.
Does anyone here have a clue as to what they mean. The reply took over a week so I am not confident that they are willing to go deeper into what they mean.
I am hoping someone here has a clue.

So far my 8010 inverter doesn't seem to care about the GTI feeding back into it. I have it set up so that when the batteries are full that a relay disconnects the GTI inverters and they just shut down as they don't see any grid.
So far it is working fine.
Hope someone can enlighten me as to Latronics cryptic answer
Pete

phil99

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Joined: 11/02/2018
Location: Australia
Posts: 2131

Posted: 07:49am 04 Sep 2024

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My guess is as GTIs are intended to push power into the grid they are concerned that if power consumption is less than total power output the GTIs will push AC back into the Latronics.

Perhaps they haven't considered you have provided your own protection and don't think their inverter can handle that.

mab1
Senior Member

Joined: 10/02/2015
Location: United Kingdom
Posts: 209

Posted: 03:15pm 04 Sep 2024

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Sounds to me like they're not saying 'no - it won't work' but just that they don't want to accept any responsibility for what happens if you try it.

If it is a transformer type using mosfets like the powerjack / 8010 / ozinverter, etc, I'm not aware of anything that would stop it working - but then there's a lot that i don't know

analog8484
Senior Member

Joined: 11/11/2021
Location: United States
Posts: 108

Posted: 09:14pm 05 Sep 2024

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Low frequency (big transformer) inverters are inherently bidirectional. Off-grid ones like your Latronics don't typically have any protection (e.g. reverse power detection shutoff) against backfeed and most are not designed or tested for the use case. So, it's understandable why Latronics would not recommend or officially support backfeed. However, it does not mean backfeed won't work technically. Having said that, backfeed may not work well depending on various factors (e.g. voltage and frequency regulation under dynamic loads or GTI anti-islanding disturbances).

Godoh
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Joined: 26/09/2020
Location: Australia
Posts: 455

Posted: 04:59am 06 Sep 2024

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Thanks for your thoughts on the subject. We have been having lots of phone and internet problems lately. Sometimes we get a 5 minute window of internet then it goes off again.
Now that the more reliable 3G network is going to close down, we will have to look for alternatives for our internet. Mobile internet on 4G is pretty hopeless where we live.
I have not been game to throw the switch yet. But I figure that if the Latronics inverter board blows up I can just use the box and transformer and put an 8010 board in. I know that they work.
Thanks again
Pete

phil99

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Joined: 11/02/2018
Location: Australia
Posts: 2131

Posted: 08:13am 06 Sep 2024

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4G may improve after 3G shuts down, provided the lower frequencies that 3G currently occupies are reallocated to 4G.
It is those lower frequencies that provide the extra range in fringe areas, greater diffraction over hills (or it might be tropospheric scatter) and less attenuation through trees.

If they are reallocated to 5G you may be no better off.

Bryan1

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Joined: 22/02/2006
Location: Australia
Posts: 1343

Posted: 08:18am 06 Sep 2024

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Pete just bite the bullet mate and get starlink then you'll never look back at loss of the net and have better speeds than this country can offer. $139 a month for unlimited within reason isn't that much to pay.

poida

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Joined: 02/02/2017
Location: Australia
Posts: 1418

Posted: 08:23am 06 Sep 2024

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+1 for starlink
I have a mobile version. it works.

wronger than a phone book full of wrong phone numbers

Godoh
Guru

Joined: 26/09/2020
Location: Australia
Posts: 455

Posted: 02:14am 07 Sep 2024

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Thanks again for the feedback. At the moment we pay $45 a month for mobile broadband. When it is working it is fine for what we do.
We don't do streaming or any of that stuff.
So we may just wait and see if when the power is back on in Tassie and the 3G shutdown goes full, what happens.
We aren't keen on paying the Starlink price, for just a bit of browsing and emails. So it is a waiting game.
Thanks again
Pete

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