My residential 10kw system went live today, with Growatt on-grid inverter using Longi Explorer 585 watt panels x 17 so a total of 9,945 watts in series. The installers set it all up as a single string with the inverter so the voltage is peaking at around 730 volts with ampere between 10-13 amps. The installers have used a 16 Amp 2-Pole DC breaker/MCB with supposed voltage rating of 1000 volts but even they claimed that this is just a 'second copy' of the breaker and they have been using these without issues.
Noticed that during peak production, the DC breaker was warm to touch so decided to look up for better breakers and to my surprise, most Alibaba breakers are available in the market along with some 'reputable' brands like CHINT and TOMZN. I also looked up Schneider 2-Pole DC breakers which I can get easily through a friend in UK/UAE but turns out, that the DC breakers they have are rated for 500 Volts only and my system would need at least something rated for 1000 Volts.
Even CHINT 2-Pole breaker is rated for 500 Volts and the only one they have which is rated for a 1000 Volts is a 4-pole one so I am wondering why there are no DC breakers easily available with 1000 Volt rating from a reputed brand like Schneider or CNC etc.? Is it that we don't need a DC breaker in solar/PV production system? Just a disconnect is enough? Because as far as I know, the inverters/PV systems these days are usually supporting 1100 volts with 13-16 amp current so DC breakers are available with a lot of varieties for amperage but voltage rating is always 500 volts and I am wondering why?
Noticed that during peak production, the DC breaker was warm to touch so decided to look up for better breakers and to my surprise, most Alibaba breakers are available in the market along with some 'reputable' brands like CHINT and TOMZN. I also looked up Schneider 2-Pole DC breakers which I can get easily through a friend in UK/UAE but turns out, that the DC breakers they have are rated for 500 Volts only and my system would need at least something rated for 1000 Volts.
Even CHINT 2-Pole breaker is rated for 500 Volts and the only one they have which is rated for a 1000 Volts is a 4-pole one so I am wondering why there are no DC breakers easily available with 1000 Volt rating from a reputed brand like Schneider or CNC etc.? Is it that we don't need a DC breaker in solar/PV production system? Just a disconnect is enough? Because as far as I know, the inverters/PV systems these days are usually supporting 1100 volts with 13-16 amp current so DC breakers are available with a lot of varieties for amperage but voltage rating is always 500 volts and I am wondering why?