Hi gurus.

Maybe I'm overthinking this or missing something important, but is there any reason I would absolutely not want to use an Automatic Transfer Switch (ATS) or maybe more simply, interlocking contactors with a hybrid inverter?

I'm thinking, one could place the ATS to switch the essential loads between grid and the backup side of the hybrid inverter to somewhat mitigate the general pain of splitting all electrics between backup/non backup loads. Thus when grid is available, the inverter would act like a grid-tie power source to both essential and non-essential loads but only supply power to the backup side when grid fails. Maybe this thinking is flawed based on my understanding that the backup side of the inverter can only deliver the max. rated backup power, say in the case of a Goodwe 5048 ES Inverter, 4.6KW. Thus, I would have to ensure that even when grid is available, anything connected to the backup side of the inverter cannot draw more than 4.6KW, or it will trip the inverter. One significant drawback I can see with an ATS would be a short interruption to the supply to the essential loads in the case of grid failure. 

According to the Goodwe manual, the inverter is rated at 4.6KW max to the grid side and the same to the backup side. Anyone have an idea if these values are simultaneous outputs or is the total output of 4.6KW shared between the grid and backup outputs?

 

 

https://powerforum.co.za/topic/1452-electrical-schematic-contactors-and-bmv702-relay/

Good luck !

😉

 

On 2019/06/29 at 8:57 PM, AlexTZA said:

Anyone have an idea if these values are simultaneous outputs or is the total output of 4.6KW shared between the grid and backup outputs? 

It is shared. Both the Goodwe and the Victron units are like this.The input and output is essentially tied together and the inverter ties with the grid (thereby feeding both from the same inverter component). When the grid fails, the backfeed relays (two series) are opened so that only the output loads remain connected to the inverter.

On 2019/06/29 at 8:57 PM, AlexTZA said:

Hi gurus.

Maybe I'm overthinking this or missing something important, but is there any reason I would absolutely not want to use an Automatic Transfer Switch (ATS) or maybe more simply, interlocking contactors with a hybrid inverter?

I'm thinking, one could place the ATS to switch the essential loads between grid and the backup side of the hybrid inverter to somewhat mitigate the general pain of splitting all electrics between backup/non backup loads. Thus when grid is available, the inverter would act like a grid-tie power source to both essential and non-essential loads but only supply power to the backup side when grid fails. Maybe this thinking is flawed based on my understanding that the backup side of the inverter can only deliver the max. rated backup power, say in the case of a Goodwe 5048 ES Inverter, 4.6KW. Thus, I would have to ensure that even when grid is available, anything connected to the backup side of the inverter cannot draw more than 4.6KW, or it will trip the inverter. One significant drawback I can see with an ATS would be a short interruption to the supply to the essential loads in the case of grid failure. 

According to the Goodwe manual, the inverter is rated at 4.6KW max to the grid side and the same to the backup side. Anyone have an idea if these values are simultaneous outputs or is the total output of 4.6KW shared between the grid and backup outputs?

 

Howdy, what ATS did you end up installing?

On 2019/06/29 at 8:57 PM, AlexTZA said:

Maybe I'm overthinking this or missing something important, but is there any reason I would absolutely not want to use an Automatic Transfer Switch (ATS) or maybe more simply, interlocking contactors with a hybrid inverter?

If you don’t like the idea of controlling things with your cell phone then you shouldn’t  go for ATS😁. I have installed contactors on essentials and non-essentials so that if the grid is down I can do my own load shedding according to my solar & battery capacity. 

On 2022/07/22 at 1:29 PM, 0 |>\/\/3|<|<3Я said:

Howdy, what ATS did you end up installing?

Hello - a bit of a delay in answering haha, but I never installed any transfer switch. The Goodwe, as with most hybrids, can deliver a decent amount of grid bypass current (I think it's around 9 kVA) over and above the 4.6kw rated backup output so it's not really necessary if working with grid available.