Insurance help?

[ap0c]

Hope to get some clarity and help from the people who have a lot more insights than myself

Setup is 3000W inverter, and has some older panels, apparently 4.45kWp
Bought a house, which has had an older solar installation - probably installed about 8y ago and has been functioning with no issues. Returned home 2Jan 2026 with burnt smell and inverter no longer functioning - decided to send to insurance. They came back and said there are too many panels for the inverter, and this is a design defect.

I did calc:
Isc PV (Maximum Input Current): 18A
Nominal Operating Voltage: 360 Vdc
Mathematically, my installed 4.45 kW array, operating at the nominal 360V, generates approximately 12.3 Amps of current (4450W / 360V = 12.36A)

This is within the manufacturer’s certified limit of 18 Amps?
Is my assumption wrong with the above?
Insurer:
4.5 Technical Assessment Summary
A 3 kVA inverter is fundamentally unsuitable for supporting a 4.45 kWp PV array, especially when coupled
with the existing connected electrical load. The system configuration is technically incorrect, non-compliant
with industry best practices/ and violates standard engineering principles for solar PV installations.
The observed inverter failure is a direct consequence of this incorrect system sizing and subsequent chronic
overloading, rather than normal wear and tear or manufacturing defect. The system was designed and
installed in a manner that guaranteed premature failure of the inverter.
This capacity mismatch dictates that the inverter was operating continuously beyond its designed limits for
power conversion and thermal dissipation. Such sustained overloading induces excessive thermal stress on
the inverter's internal components. Furthermore, the inverter is not adequately sized to handle the electrical
load being drawn through the system, exacerbating the overstress condition.
Inverter spec:
From the Inverter: Model No. : EPHS-ICON-1P-01A Serial No. : 96131604100418

Section	Specification	Value
PV INPUT	Nominal operating voltage	360Vdc
Vmax PV	500Vdc
Isc PV	18A
MPPT voltage range	250 - 450Vdc
GRID/AC OUTPUT	Nominal operating voltage	230 Vac
Maximum output current	17A
Nominal operating frequency	50Hz
Maximum power	3000W
Power factor range	0.9 lead-0.9lag
AC INPUT	Nominal operating voltage	230 Vac
Maximum input current	30A
Nominal operating frequency	50Hz
BATTERY	Battery voltage range	42-56Vdc
Minimum capacity	125Ah
Maximum battery current	82A

 

[Tomtomtom]

In principle there's no reason you can't oversize your solar capacity vs your inverter's max usable power input and this is common.

However you are limited by Voc. You can't just assume 360 V, you need to know the rating of your panels and how they're arranged. In a series string you could be well over 500 V and exceeding the Vmax of the inverter.

A decent inverter won't just blow up under excessive load because it can curtail its own output. But it can't do anything about overvoltage on the input and that's where your risk lies. Ironically at the lowest loads on a cold sunny day is when you're closest to Voc.

OTOH if it's survived 8 years I'm doubting it's that. Most likely just that's just the lifespan of that particular device. Either way I'd be surprised if it's an insured risk.

 

[ap0c]

Thanks for your help. Was just interesting that it is insured risk, but they said if its 3000W inverter, you cant have more than 3000W overpaneling..... I will investigate the 360V - thank you for your help. Apprecaite.

 

[Tomtomtom]

Thanks for your help. Was just interesting that it is insured risk, but they said if its 3000W inverter, you cant have more than 3000W overpaneling..... I will investigate the 360V - thank you for your help. Apprecaite.

Insurance covers external events like lightning strikes or surges from the grid. It doesn't cover the normal deterioration of a device over time, and it especially doesn't cover accelerated deterioration due to misuse. They're of course looking for the easiest way to repudiate your particular claim, but they are probably not wrong to repudiate it anyway.

If you came back to them with an engineer's report saying the overpaneling was not the cause then they would just move on to the next thing - do you have valid COCs, surge protectors, lightning rods, maintenance records, building plans, a weather report, who knows.

 

[ghaye]

That technical assessment could not have been done by somebody that understands electricity. It's hot garbage. Do you have a broker or is this a direct insurance company?

 

[Tomtomtom]

That technical assessment could not have been done by somebody that understands electricity. It's hot garbage. Do you have a broker or is this a direct insurance company?

It doesn't matter, the outcome will be the same. An insurer is not a substitute for an appliance warranty, they're covering specific risks (events).

 

[ghaye]

It doesn't matter, the outcome will be the same. An insurer is not a substitute for an appliance warranty, they're covering specific risks (events).

Unless the damage is attributable to a lightning strike or grid surge etc.

But it's definitely NOT what their technical assessment says.

 

[Neuk_]

Thanks for your help. Was just interesting that it is insured risk, but they said if its 3000W inverter, you cant have more than 3000W overpaneling..... I will investigate the 360V - thank you for your help. Apprecaite.

That is just pure nonsense, the inverting capacity of the inverter is one thing, the MPPT capacity is another, and they are not generally linked. Take our 8kw single phase Sunsynk, it is rated at 8kW inverting capacity but the MPPT is rated at 10.4kW, there are voltage and amperage limits to consider as well though. Even our old 3kVa Victron was coupled via an MPPT to 3.6kW worth of solar panels, it is somewhat normal to have the allowable PV capacity be higher than inverter capacity.

 

[Tongs of Destiny]

Hope to get some clarity and help from the people who have a lot more insights than myself

Setup is 3000W inverter, and has some older panels, apparently 4.45kWp
Bought a house, which has had an older solar installation - probably installed about 8y ago and has been functioning with no issues. Returned home 2Jan 2026 with burnt smell and inverter no longer functioning - decided to send to insurance. They came back and said there are too many panels for the inverter, and this is a design defect.

I did calc:
Isc PV (Maximum Input Current): 18A
Nominal Operating Voltage: 360 Vdc
Mathematically, my installed 4.45 kW array, operating at the nominal 360V, generates approximately 12.3 Amps of current (4450W / 360V = 12.36A)

This is within the manufacturer’s certified limit of 18 Amps?
Is my assumption wrong with the above?
Insurer:
4.5 Technical Assessment Summary
A 3 kVA inverter is fundamentally unsuitable for supporting a 4.45 kWp PV array, especially when coupled
with the existing connected electrical load. The system configuration is technically incorrect, non-compliant
with industry best practices/ and violates standard engineering principles for solar PV installations.
The observed inverter failure is a direct consequence of this incorrect system sizing and subsequent chronic
overloading, rather than normal wear and tear or manufacturing defect. The system was designed and
installed in a manner that guaranteed premature failure of the inverter.
This capacity mismatch dictates that the inverter was operating continuously beyond its designed limits for
power conversion and thermal dissipation. Such sustained overloading induces excessive thermal stress on
the inverter's internal components. Furthermore, the inverter is not adequately sized to handle the electrical
load being drawn through the system, exacerbating the overstress condition.
Inverter spec:
From the Inverter: Model No. : EPHS-ICON-1P-01A Serial No. : 96131604100418

Section	Specification	Value
PV INPUT	Nominal operating voltage	360Vdc
Vmax PV	500Vdc
Isc PV	18A
MPPT voltage range	250 - 450Vdc
GRID/AC OUTPUT	Nominal operating voltage	230 Vac
Maximum output current	17A
Nominal operating frequency	50Hz
Maximum power	3000W
Power factor range	0.9 lead-0.9lag
AC INPUT	Nominal operating voltage	230 Vac
Maximum input current	30A
Nominal operating frequency	50Hz
BATTERY	Battery voltage range	42-56Vdc
Minimum capacity	125Ah
Maximum battery current	82A

Did this insurance assessor ask or check the panels? They would have to check the panels voltage etc, its written underneath them, it has nothing to do with wattage. You can have 900000000W going into an inverter, it doesn't care it just clips the excess.. what does matter is the DC voltage (the Voc)

If this assessor just looked at your system and said, "oh too many panels" without actually doing the maths and double checking the Voc with relation to your inverter <-- red flag, get a second opinion or get someone with a brain.

Do you have your panels name / model etc, easy to look up specs.

 

[ghaye]

Did this insurance assessor ask or check the panels? They would have to check the panels voltage etc, its written underneath them, it has nothing to do with wattage. You can have 900000000W going into an inverter, it doesn't care it just clips the excess.. what does matter is the DC voltage (the Voc)

If this assessor just looked at your system and said, "oh too many panels" without actually doing the maths and double checking the Voc with relation to your inverter <-- red flag, get a second opinion or get someone with a brain.

Do you have your panels name / model etc, easy to look up specs.

Correct, but the system cannot run like that for years and then just suddenly let the smoke out. It would have happened the first time the voltage went too high. This assessor is clueless.

 

[chrisc]

I have written many reports of damaged electronic equipment to support insurance claims

Is the assessor qualified to issue a report which is basically guesswork - his reasoning is false?

Reading your initial description the motivation for a claim is not good. The fault may be attributed to wear and tear, not an insurable event