Hedges
I See Electromagnetic Fields!
- Joined
- Mar 28, 2020
- Messages
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I have a fairly big grid-backup system.
Four SI-6048US wired 2s2p. Pass-thru from grid is 112A 120/240V
Continuous rated inverter output 4 x 5750W = 23kW, surge 4 x 11kW = 44kW for 3 seconds
Each has 2/0 cable to 48V battery. Battery is way undersize at 400 Ah, but inverter settings support up to 100,000 Ah.
With one or more inverters and/or one or more battery strings in parallel, busbar doesn't carry full current through it's cross section. On negative side, my busbar has 3 holes with battery in middle and 2 inverters on either side. Positive side two cables branch off to fuses.
11kW x 4 / 42V / 90% x 112% = 1300A. Split two ways, 650A for 3 second surge; continuous would he half that.
(112% is my ripple factor, battery current follows sine wave because capacitors can't supply. RMS current is 12% higher than average)
I have about 12kW of AC coupled Sunny Boy. If off-grid (so doesn't overload relay), can support 48kW of Sunny Boy. With PV array split and oriented for morning and afternoon sun, about 80 kW STC of PV would be a good fit.
If you want a larger system, go three phase. Each cluster is 3x SI-6048US and its own battery. Then you connect several clusters.
Four SI-6048US wired 2s2p. Pass-thru from grid is 112A 120/240V
Continuous rated inverter output 4 x 5750W = 23kW, surge 4 x 11kW = 44kW for 3 seconds
Each has 2/0 cable to 48V battery. Battery is way undersize at 400 Ah, but inverter settings support up to 100,000 Ah.
With one or more inverters and/or one or more battery strings in parallel, busbar doesn't carry full current through it's cross section. On negative side, my busbar has 3 holes with battery in middle and 2 inverters on either side. Positive side two cables branch off to fuses.
11kW x 4 / 42V / 90% x 112% = 1300A. Split two ways, 650A for 3 second surge; continuous would he half that.
(112% is my ripple factor, battery current follows sine wave because capacitors can't supply. RMS current is 12% higher than average)
I have about 12kW of AC coupled Sunny Boy. If off-grid (so doesn't overload relay), can support 48kW of Sunny Boy. With PV array split and oriented for morning and afternoon sun, about 80 kW STC of PV would be a good fit.
If you want a larger system, go three phase. Each cluster is 3x SI-6048US and its own battery. Then you connect several clusters.
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