Minimum Battery System Capacity
The Discover Lithium Battery and Selectronic 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 inverter-chargers and solar charge controllers in the system. Additionally, battery peak capacity must support the surge requirements demanded by the load attached to the inverter-charger. Match all inverter-charger peak power values with the sum of all battery peak battery current values.
Inverter Peak = (Inverter Surge Value) / (Inverter Efficiency) / (48V: Low Battery Cut-Off)
Single-Phase Models | Inverter Peak (20 seconds) | Max Continuous Charge | Max Continuous Discharge | AES RACKMOUNT 48-48-5120/ | HELIOS ESS |
|---|---|---|---|---|---|
SPMC480-AU | 184 A (1) | 73 ADC | 83 ADC | 2 | 1 |
SPMC481-AU | 262 A (1) | 104 ADC | 119 ADC | 2 | 1 |
SPMC482-AU | 391 A (1) | 156 ADC | 179 ADC | 3 | 2 |
(1) Calculated based on the surge power and efficiency CEC published in Selectronic SP PRO Series 2i Instruction Manual (Doc OI0003 Part 004122 Rev 42 - Feb 2023).
(2) Discover AES RACKMOUNT 48-48-5120/48-48-5120-H Battery, Peak Power: 218 A RMS (3 seconds), 95 A DC Continuous Charge/Discharge (reduced to 65 A to compensate for noise), as published in Discover AES RACKMOUNT Installation and Operation Manual (805-0043 Rev J).
(3) Discover HELIOS ESS 52-48-16000 Battery, Peak Power: 300 A RMS (15 seconds), 200 A Max Continuous Charge/Discharge (reduced to 150 A to compensate for noise), as published in the Discover HELIOS ESS Installation and Operation Manual - Australia (805-0100).