OFF-grid solar inverter Growatt SPF 5000 ES - electric shock!!!
666 بار بازدید -
2 سال پیش
-
If you own Growatt SPF
If you own Growatt SPF 5000 ES or SPF 3500 ES solar inverter please read the description below.
I was trying to find out why inverter behavior was erratic at higher load (3000 W and more for 5000 W inverter model). And by pure coincidence I found that four screws, on the top of the inverter, were not grounded! I experienced “light” but unpleasant electric shock when I touched one of the screws and not-grounded metal bar mounted on the not completely dry wall (capillary moisture). I measured approximately 120 VAC between each screw and the ground wire in the wall socket. Rest of the enclosure was properly grounded (0 VAC between enclosure and the ground wire).
Top four screws are holding EMI filter or switcher chokes. Filter ground connection should probably be made with those four screws. But there was no connection between the screws and the enclosure. Contact was prevented by a layer of paint on screw holes. Because the EMI filter was not grounded electromagnetic disturbances were not pushed/diverted into the ground potential.
After I removed the layer of paint on the screw holes and re-tightening all the screws I measured 0 VAC between the four screws and the ground wire (possibility of electric shock was eliminated). Also inverter started to work as it should. There was no more erratic behavior (random disconnection of PV panels which resulted in switching between the utility grid and PV panels – SOLAR or SUB function, no battery connected).
Fault is no coincidence. It is probably production fault. I purchased the second SPF 5000 ES inverter, from different seller, and I also found no-ground connection fault on that inverter.
I was trying to find out why inverter behavior was erratic at higher load (3000 W and more for 5000 W inverter model). And by pure coincidence I found that four screws, on the top of the inverter, were not grounded! I experienced “light” but unpleasant electric shock when I touched one of the screws and not-grounded metal bar mounted on the not completely dry wall (capillary moisture). I measured approximately 120 VAC between each screw and the ground wire in the wall socket. Rest of the enclosure was properly grounded (0 VAC between enclosure and the ground wire).
Top four screws are holding EMI filter or switcher chokes. Filter ground connection should probably be made with those four screws. But there was no connection between the screws and the enclosure. Contact was prevented by a layer of paint on screw holes. Because the EMI filter was not grounded electromagnetic disturbances were not pushed/diverted into the ground potential.
After I removed the layer of paint on the screw holes and re-tightening all the screws I measured 0 VAC between the four screws and the ground wire (possibility of electric shock was eliminated). Also inverter started to work as it should. There was no more erratic behavior (random disconnection of PV panels which resulted in switching between the utility grid and PV panels – SOLAR or SUB function, no battery connected).
Fault is no coincidence. It is probably production fault. I purchased the second SPF 5000 ES inverter, from different seller, and I also found no-ground connection fault on that inverter.
2 سال پیش
در تاریخ 1401/03/02 منتشر شده
است.
666
بـار بازدید شده