Magnum Energy Integration Guide

REV
20201125
SimpliPhi Power, Inc. | 3100 Camino Del Sol | Oxnard, CA 93030, USA | [phone] | [e-mail] | SimpliPhiPower.com
| 7 |
3.2 – Charge Calculation: Charge Controller Power Bank Sizing
To optimize solar harvesting, a properly sized PHI battery bank should be able to accept the maximum PV
charge current. To determine the minimum number of PHI batteries required to optimize PV, divide the output
of the charge controller(s) by the “max continuous charge current” per PHI battery. Be sure to verify the “max
continuous charge current” for the PHI battery model that you’re using, because it may differ from C/2
depending on the model.
Charge Example A
This example uses the following calculation:
B
#PV
≥ I
PVChrgMax
/ I
BatChrgMax
This example assumes the following:
• Max. continuous charge current for PHI 3.8 48V = 37.5A
• PV charge controller max = 100A
The calculation and assumptions correspond to:
B
#PV
≥ 100A/37.5A = 2.67
In this example, a properly sized PHI battery bank based on the available PV charge has a minimum of 3
batteries. This maximizes the use of available PV while ensuring the batteries are never stressed by
overcharging. If the PHI battery bank includes fewer batteries than calculated, configure the charge controller
settings to limit the controller’s current output. These settings are described in more detail in the following
sections of this Integration Guide.
Charge Example B
This example uses the following calculation:
B
#PV
≥ I
PVChrgMax
/ I
BatChrgMax
This example assumes the following:
• Max. continuous charge current for PHI 3.8 24V = 75A
• PV charge controller max = 200A
The calculation and assumptions correspond to:
B
#PV
≥ 200A755A = 2.66
In this example, a properly sized PHI battery bank based on the available PV charge also has a minimum of 3
batteries.
In summary: When designing a system using the Discharge Calculation and the Charge Calculation, the
minimum number of batteries should be the greater of the two sizing calculation results.