Minimum Battery System Capacity
The Discover Lithium Battery and SAJ device automatically manage the battery charge and discharge rates. Using large solar arrays with battery banks that are too small can exceed the operating limits of the battery to charge and possibly lead to the BMS triggering over-current protection. Battery capacity must accept the maximum charge current of the system, or charging must be curtailed below the operating limit of the installed batteries. Derive this value by adding together the charge capacities of all inverters and solar charge controllers in the system. Additionally, battery peak capacity must support the surge requirements demanded by the load attached to the inverter. Match all inverter peak power values with the sum of all battery peak current values.
Inverter Peak = (Inverter Surge Value) / (Inverter Efficiency) / (48V: Low Battery Cut-Off)
Models | Inverter Peak (10 seconds) | Max Continuous Charge | Max Continuous Discharge | AES RACKMOUNT | HELIOS ESS |
|---|---|---|---|---|---|
H2-5K-LS3-US | 245 A (1) | 160 A | 160 A | 2 | 1 |
H2-7.6K-LS3-US | 245 A (1) | 160 A | 160 A | 2 | 1 |
H2-9.6K-LS4-US | 367 A (2) | 240 A | 240 A | 3 | 2 |
H2-11.4K-LS4-US | 367 A (2) | 240 A | 240 A | 3 | 2 |
(1) Calculated based on overload power of 11400 W (10 seconds), 97% battery max efficiency, as published in the H2 Series Hybrid Solar Inverter User Manual.
(2) Calculated based on overload power of 17100 W (10 seconds), 97% battery max efficiency, as published in the H2 Series Hybrid Solar Inverter User Manual.
(3) Discover AES RACKMOUNT 48-48-5120/48-48-5120-H Battery, Peak Power (3 seconds): 218 A RMS, 95 A DC Continuous Charge/Discharge (1 hour), as published in Discover AES RACKMOUNT Installation and Operation Manual (805-0043 Rev J).
(4) Discover HELIOS ESS 52-48-16000 Battery, Peak Discharge Current (15 seconds): 300 A RMS, 200 A Continuous Charge/Discharge, as published in Discover HELIOS ESS Installation and Operation Manual (805-0090 Rev D).