B
bigsparks
Hi
I have installed our first PV system, which we are using to get MCS accredited with. Its a small 5 panel system as roof space is quite small. The panels are 195w each.
The Voc for the panels @ STC is 45.21V and Isc @ STC 5.56A.
Our measured Voc on the day of commissioning was 211V. I thought this was reasonable as the Voc of array is 226.05V at STC. Our measured Isc on the day was 1.4A with an irradiance measurement of 270w/m2. Which when we adjusted figures to STC was nigh on perfect for the array. From these results we assume that the DC side of the install is performing as it should.
On our AC side at the inverter plug, we have 245V which is also the reading inside the inverter at the AC connections so I know that 245v AC is reaching the inverter.
However, the sma sunny boy 1200 is completely dead. No lights, no warning signs, no green flashing lights nothing. After triple checking our AC & DC tests again I thought that it must be a problem with th inverter. I got another exact model delivered and again nothing, no lights, no warning messages, completely dead.
Now ive tried getting hold of SMA technical in Germany as detailed on the manual but cant get to speak to anyone.
The min DC voltage input that the inverter needs at start up is 120V, so we are well within that tolerance. I wondered whether the 1200w inverter supplied was to big for the 975w array but the manual says that a green light should flash if the array is not prducung enough power to invert.
We had our MCS assessment yesterday, which we passed, but on the condition that they will need proof of the inverter working before we will get signed off.
Before I buy another inverter, ie a smaller mastervolt or the like, I wanted to see if anyone had any guidance or knowledge that 2 sparks and and mcs assessor could not see.
Any help appreciated.
Cheers
I have installed our first PV system, which we are using to get MCS accredited with. Its a small 5 panel system as roof space is quite small. The panels are 195w each.
The Voc for the panels @ STC is 45.21V and Isc @ STC 5.56A.
Our measured Voc on the day of commissioning was 211V. I thought this was reasonable as the Voc of array is 226.05V at STC. Our measured Isc on the day was 1.4A with an irradiance measurement of 270w/m2. Which when we adjusted figures to STC was nigh on perfect for the array. From these results we assume that the DC side of the install is performing as it should.
On our AC side at the inverter plug, we have 245V which is also the reading inside the inverter at the AC connections so I know that 245v AC is reaching the inverter.
However, the sma sunny boy 1200 is completely dead. No lights, no warning signs, no green flashing lights nothing. After triple checking our AC & DC tests again I thought that it must be a problem with th inverter. I got another exact model delivered and again nothing, no lights, no warning messages, completely dead.
Now ive tried getting hold of SMA technical in Germany as detailed on the manual but cant get to speak to anyone.
The min DC voltage input that the inverter needs at start up is 120V, so we are well within that tolerance. I wondered whether the 1200w inverter supplied was to big for the 975w array but the manual says that a green light should flash if the array is not prducung enough power to invert.
We had our MCS assessment yesterday, which we passed, but on the condition that they will need proof of the inverter working before we will get signed off.
Before I buy another inverter, ie a smaller mastervolt or the like, I wanted to see if anyone had any guidance or knowledge that 2 sparks and and mcs assessor could not see.
Any help appreciated.
Cheers
