APstorage Installation / User Manual
19
3. Installation
3.6 PV System to APstorage Pairing
1.
Identify the largest maximum single load power rating (kW) that you want to backup, and
select the absolute minimum number of PCS units required to meet the 2017 NEC
690.10->710.15(A) requirements. The maximum allowed number of ELS-5K units that can be
connected in parallel is 2.
2. Based on the estimated backup loads for the user defined time period, calculate the required
energy storage (kWh) capacity and the minimum number of battery required.
3. Refer the Table 1 to calculate the maximum PV system power (PV system 1) to connect to the
backup side, if the total PV system power is larger than Max PV system power, connect the
excess power (PV system 2) to the grid side.
Table 1: Maximum PV system power for storage system for backup operation
ELS-5K units
Battery units
Max PV system power (kWac)
1
1
3.75
1
>=2
7.5
2
2
7.5
2
3
11.25
2
>=4
15
