Balcony solar PV

[richbee]

Possibly a daft question for the Hoymiles inverter - the HM-800 will take up to 2 panels up to 500W, but states max voltage of 60V. I was assuming that the voltage would be added between the 2 panels, and all the panels seem to have at least 30V, with max of 32-33V - so it would not be a good idea to have an over-voltage - or have I misunderstood?

There is no such thing as a daft question, 13 years ago I knew nothing about panels and inverters.

The HM-800 will have two sets of inputs, so one panel per input. If you connect two panels in series to a single input you will kill the inverter.

By connecting one panel to each input, the panels connect in parallel so it adds up the current and not the voltage. Over voltage kills inverters stone dead and its the open circuit voltage of the panels that is important which is higher than the max power voltage which I suspect your quoting. Also its good practice to add about 5% on top of the open circuit voltage to allow for very cold temperatures as panel voltage increases with colder temperatures.

Thanks Nowty - that makes complete sense - You are right, the open circuit voltage is ~37V - so in parallel no problem if rated to 60V.

[richbee]

Right - now looking at all the Hoymiles options....

The amazon HM-800 for £130 seems a bit cheap - from Germany with no mention of customs duty etc..

I just realised that the HMS-1600 has 4 MPPTs, so it would do exactly what I want. Ebay has one from Germany for ~£200.
I asked the seller about customs and he referred me to the UK Gov website...deep joy.
Searching for commodity codes throws up 8504 4085 90 - for an Inverter <7.5kVA - not for aircraft use - and seems to show 0% import duty, which would be good if it was accurate. It suggests that only the 20% VAT is payable...

I know Tay had quite a wait for the arrival and customs processing - is there any way to pre-empt it and avoid the DHL extra charges?

[Joeboy]

Right - now looking at all the Hoymiles options....

The amazon HM-800 for £130 seems a bit cheap - from Germany with no mention of customs duty etc..

I just realised that the HMS-1600 has 4 MPPTs, so it would do exactly what I want. Ebay has one from Germany for ~£200.
I asked the seller about customs and he referred me to the UK Gov website...deep joy.
Searching for commodity codes throws up 8504 4085 90 - for an Inverter <7.5kVA - not for aircraft use - and seems to show 0% import duty, which would be good if it was accurate. It suggests that only the 20% VAT is payable...

I know Tay had quite a wait for the arrival and customs processing - is there any way to pre-empt it and avoid the DHL extra charges?

Nope. I was about £50. I'd be happy to hear of a way round it though for next time.

Your prices are good. I was 260 Euro for the hms800

[Tay]

Possibly a daft question for the Hoymiles inverter - the HM-800 will take up to 2 panels up to 500W, but states max voltage of 60V. I was assuming that the voltage would be added between the 2 panels, and all the panels seem to have at least 30V, with max of 32-33V - so it would not be a good idea to have an over-voltage - or have I misunderstood?

There is no such thing as a daft question, 13 years ago I knew nothing about panels and inverters.

The HM-800 will have two sets of inputs, so one panel per input. If you connect two panels in series to a single input you will kill the inverter.

By connecting one panel to each input, the panels connect in parallel so it adds up the current and not the voltage. Over voltage kills inverters stone dead and its the open circuit voltage of the panels that is important which is higher than the max power voltage which I suspect your quoting. Also its good practice to add about 5% on top of the open circuit voltage to allow for very cold temperatures as panel voltage increases with colder temperatures.

Totally agree, I did notice the voltage on the hoymiles was/is quite low, but they have pretty reasonable prices for the dual & quad port devices to get around those issues. there are also minor differences between the HM and HMS versions, the HMS version for example allowing slightly larger panels with its 65v max input per port, the HMS is a slightly larger size too for some reason, presumably heat dissipation.

The whole voltage thing 'could' be a marketing exercise to increase sales (as you need more devices) or being a german design simply to keep the heat down and allow longer life.

Either way, they are leagues ahead of the 'no name' chinese copy brands as Joeboy and myself have seen.

I fully intend to keep mine even when I transition to a more static solution. I like the kit and feels good in the hands and allows me to fiddle around without knackering a static setup.

I have also considered swapping my office.workshop back to the mains circuit when I put my new 435w panels up (allowing me to flog the Bluetti for say a nice new Pylontech battery ), even a single 295w panel was 50w shy of feeding back to the grid today. so I either keep it small or give it a bigger load. I see no resolution on the horizon for my BG issues.

[Tay]

Right - now looking at all the Hoymiles options....

The amazon HM-800 for £130 seems a bit cheap - from Germany with no mention of customs duty etc..

I just realised that the HMS-1600 has 4 MPPTs, so it would do exactly what I want. Ebay has one from Germany for ~£200.
I asked the seller about customs and he referred me to the UK Gov website...deep joy.
Searching for commodity codes throws up 8504 4085 90 - for an Inverter <7.5kVA - not for aircraft use - and seems to show 0% import duty, which would be good if it was accurate. It suggests that only the 20% VAT is payable...

I know Tay had quite a wait for the arrival and customs processing - is there any way to pre-empt it and avoid the DHL extra charges?

Yup, I was at the mercy of UK Border force/customs, I'd do it again though as the kit is just really good.

if I recall correctly, the unit had left Germany in less than 2 days, the rest was faffing about in the UK, the sorry saga is in this thread somewhere, I recall 'somebody' in the UK sitting on posting a letter asking for import tax payment before they would release the item, 5-7 days just to get the letter. It was shocking service, nothing to do with the German folks I hasten to add.

I would suggest if you find what you want talking, to the folks first, I had an order from Amazon cancelled as they said they wouldnt ship to the UK, and more recently had an order from Germany via eBay that effectively let me get to checkout then faffed about 3-4 times due to me being in the UK.

Several of us have had good experiences with offgridtec-com via eBay, I'm sure there are others but these guys just got the job done for a decent price. But I couldnt see anyway to soften the tax blow.

Bimble balcony kit have the HMS-800-2T in a kit, you might be able to pursuade them to part with one perhaps??

[openspaceman]

What would be the position if it were brought in as hand luggage, could you pay the 20% VAT at customs?

Can these things be connected, lawfully, to the UK electricity network yet?

[Tay]

What would be the position if it were brought in as hand luggage, could you pay the 20% VAT at customs?

Can these things be connected, lawfully, to the UK electricity network yet?

I'm not sure they can legally be used in the UK (technically they obviously can as this thread shows), it was mentioned previously, that the UK grid appears to quite a way behind Europe in terms of the 'grid' in capacity/capability/technology etc, we just dont have the infrastructure that others have. EU if I recall, have a 800w cap currently, but that might be set to come up a bit.

If you were to bring one of those in they 'could' I guess hit you with import duty. I don't 'think' you'd get hit with VAT as VAT is already paid if you got it from Germany say

My couriered one specifically listed import duty as opposed to vat. then courier charges + vat on those charges/handling/[its a SunnyDayTax] etc.

[chris_n]

I'm not sure they can legally be used in the UK (technically they obviously can as this thread shows), it was mentioned previously, that the UK grid appears to quite a way behind Europe in terms of the 'grid' in capacity/capability/technology etc, we just dont have the infrastructure that others have. EU if I recall, have a 800w cap currently, but that might be set to come up a bit.

If you were to bring one of those in they 'could' I guess hit you with import duty. I don't 'think' you'd get hit with VAT as VAT is already paid if you got it from Germany say

My couriered one specifically listed import duty as opposed to vat. then courier charges + vat on those charges/handling/[its a SunnyDayTax] etc.

Germany currently has a 600W limit on what is a simplified process for informing your provider, Austria and some others are 800W. The German industry is lobbying for this to be upped to 800W so that is why you will see many units that say 600W upgradable to 800W. If they have G98 or whatever certification (I believe the Hoymiles has) they can be connected to UK grid but you must inform the DNO. As the UK uses a ring main system for many circuits and it is possible to overload the wiring by bypassing the circuit breakers the regulations do not permit plugging them in to a socket. If they are appropriately certified they can legally be connected to a dedicated circuit. Whether or not you feel it is necessary to comply with all of the regs is entirely up to the individual.

[Tay]

Digging a littler further as I did see something about that Bimble bundled HMS-800 having approval in the UK, typically I cant find it now

But the ENA does have a bit of info on the Hoymiles kit, but seems to have different model numbers. Some of them even have G98 for the UK but not sure how they tie into the current HM- and HMS- range of microinverters.

[nowty]

Digging a littler further as I did see something about that Bimble bundled HMS-800 having approval in the UK, typically I cant find it now

But the ENA does have a bit of info on the Hoymiles kit, but seems to have different model numbers. Some of them even have G98 for the UK but not sure how they tie into the current HM- and HMS- range of microinverters.

The HMS-800-2T model quoted in the Bimble bundle appears to be approved,
https://www.ena-eng.org/gen-ttr/Index?A ... tab=search