I have a Luxpower SNA 5000 on my house, with 7.4kw of Lithium batteries and 3.6kW of solar. Professionally installed over a year ago with COC. House is about 40 years old and electrics are ok but not updated. Still old school samite breakers etc.

Had an issue about 6 months ago with earth leakage tripping when grid comes back. To clarify we were powered from battery throughout load shedding but then went dark when it came back. I replaced the EL with a new DIN one and it never recurred.

 

A few weeks ago I bought a new home theatre system. Not a Game special but the stuff you get from specialised shops.

Within a day the amp went into protection mode and I had to return it to the manufacturer. They found the fuse blown and said it was likely a power surge. As I'm on an inverter, I thought this was unlikely, but when I reinstalled it and started to play it I found that the subwoofer (Also new but different brand) had also blown its fuse. I replaced it and decided to put them on a surge protection multi plug.

A week later and they have both popped their fuses again. Around the time of the failure the inverter switched from grid to battery supply. I could understand a possible out of sync situation at the end of load shedding but not when the grid drops as everything should be synced at that point. Also, how is this happening behind surge protection?

I'm at a bit of a loss where to start. Inverter? House wiring?

 

38 minutes ago, Hagu13 said:

I have a Luxpower SNA 5000 on my house, with 7.4kw of Lithium batteries and 3.6kW of solar. Professionally installed over a year ago with COC. House is about 40 years old and electrics are ok but not updated. Still old school samite breakers etc.

Had an issue about 6 months ago with earth leakage tripping when grid comes back. To clarify we were powered from battery throughout load shedding but then went dark when it came back. I replaced the EL with a new DIN one and it never recurred.

 

A few weeks ago I bought a new home theatre system. Not a Game special but the stuff you get from specialised shops.

Within a day the amp went into protection mode and I had to return it to the manufacturer. They found the fuse blown and said it was likely a power surge. As I'm on an inverter, I thought this was unlikely, but when I reinstalled it and started to play it I found that the subwoofer (Also new but different brand) had also blown its fuse. I replaced it and decided to put them on a surge protection multi plug.

A week later and they have both popped their fuses again. Around the time of the failure the inverter switched from grid to battery supply. I could understand a possible out of sync situation at the end of load shedding but not when the grid drops as everything should be synced at that point. Also, how is this happening behind surge protection?

I'm at a bit of a loss where to start. Inverter? House wiring?

 

I belief one has to trace the reason for this happening. One of our learned members sited a brief DC surge. We have also found clients having fuses blown the moment of switching between grid and inverter. 

A starting point would be to get one of our electronic guys to put a scope on the AC output during switching to ensure the output is AC and not a brief DC pulse. DC applied to any transformer PSU will cause a high current to blow the normal fuse. 

In which area of SA are you based? 

@Scorp007 beat me to it....

We had a similar complaint here about 2 or 3 weeks ago.  I don't seem to recall that there was a specific resolution.

Your home theatre AV receiver/amp will likely use a conventional mains transformer.  Your sub-woofer is a 50/50 chance that it too will use a 50Hz transformer.  If not, it will use a switch-mode power supply (SMPS).  A SMPS rectifies the AC to DC first and would be happy to work with DC inputs as well.  A conventional transformer however, would immediately saturate (magnetically) when presented with a DC voltage.  Such a condition would blow the fuse.

It is speculated that an inverter might misbehave due to buggy software, whereby the 230VAC output momentarily goes DC at switch over.  This would explain why most electronics would work quite happily, as most uses SMPSs.  Older equipment, or anything that uses a conventional 50Hz transformer, will possible blow a fuse.  A very small transformer such as might be used in an old clock radio might not actually be fused and could possibly get damaged by such an event.

I can't remember if the other complaint was also from a Luxpower inverter.

To confirm the theory, one would need to check the 230VAC with an oscilloscope and electricians don't normally have access to this equipment .I will try and search for the other thread.  If that was also a Luxpower then this becomes very suspicious.  If the theory is correct, it should be possible to fix the problem by upgrading the firmware.

16 minutes ago, Modina said:

@Scorp007 beat me to it....

We had a similar complaint here about 2 or 3 weeks ago.  I don't seem to recall that there was a specific resolution.

Your home theatre AV receiver/amp will likely use a conventional mains transformer.  Your sub-woofer is a 50/50 chance that it too will use a 50Hz transformer.  If not, it will use a switch-mode power supply (SMPS).  A SMPS rectifies the AC to DC first and would be happy to work with DC inputs as well.  A conventional transformer however, would immediately saturate (magnetically) when presented with a DC voltage.  Such a condition would blow the fuse.

It is speculated that an inverter might misbehave due to buggy software, whereby the 230VAC output momentarily goes DC at switch over.  This would explain why most electronics would work quite happily, as most uses SMPSs.  Older equipment, or anything that uses a conventional 50Hz transformer, will possible blow a fuse.  A very small transformer such as might be used in an old clock radio might not actually be fused and could possibly get damaged by such an event.

I can't remember if the other complaint was also from a Luxpower inverter.

To confirm the theory, one would need to check the 230VAC with an oscilloscope and electricians don't normally have access to this equipment .I will try and search for the other thread.  If that was also a Luxpower then this becomes very suspicious.  If the theory is correct, it should be possible to fix the problem by upgrading the firmware.

The other thread was a luxpower as well

I have problems searching on powerforum...  I now used an external search.  There seem to be more than one thread as the one I found does not include the long discussion we had.
 

I think you should definitely take this up with Luxpower.  This seems to be a general complaint with these inverters.

Edited May 22, 20233 yr by Modina

Thanks everyone

Starting to look like a DC pulse maybe. Common to both threads is Luxpower and an AV amp fuse going at switchover from grid to battery. Other user seems to have an existing ampo and a new Luxpower, mine is existing Luxpower and a new amp and sub.

I'm not seeing feedback of a resolution on the other one. I'll drop him a message and also see if Luxpower are helpful

Please let us know if/how you can resolve the problem.

On 2023/05/22 at 8:51 AM, Hagu13 said:

I have a Luxpower SNA 5000 on my house, with 7.4kw of Lithium batteries and 3.6kW of solar. Professionally installed over a year ago with COC. House is about 40 years old and electrics are ok but not updated. Still old school samite breakers etc.

Had an issue about 6 months ago with earth leakage tripping when grid comes back. To clarify we were powered from battery throughout load shedding but then went dark when it came back. I replaced the EL with a new DIN one and it never recurred.

 

A few weeks ago I bought a new home theatre system. Not a Game special but the stuff you get from specialised shops.

Within a day the amp went into protection mode and I had to return it to the manufacturer. They found the fuse blown and said it was likely a power surge. As I'm on an inverter, I thought this was unlikely, but when I reinstalled it and started to play it I found that the subwoofer (Also new but different brand) had also blown its fuse. I replaced it and decided to put them on a surge protection multi plug.

A week later and they have both popped their fuses again. Around the time of the failure the inverter switched from grid to battery supply. I could understand a possible out of sync situation at the end of load shedding but not when the grid drops as everything should be synced at that point. Also, how is this happening behind surge protection?

I'm at a bit of a loss where to start. Inverter? House wiring?

 

Hi, make sure that the inverter is on UPS  and not APL. I had the same issue with my Marantz and Denon units and since changing the setting.... no more popping fuses.

Hi, I'm also having the same issue of blowing my Sony AV receiver & Sony Subwoofer. Inverter is set on UPS. Is there a solution for this problem? Please help. From Livhuwani 

Hi, I'm having the same issue. Both Sony receiver and subwoofer fuse blowned during change over from grid to battery. Inverter is set on UPS. Is there a solution to this problem? 

I had the same issue. But then it stopped by itself. But it is possible that the installer did a software upgrade in mean time remotely. I will find out from him.
But suddenly did the same yesterday after a few months.