Magnum Energy Integration Guide

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Battery Bank Sizing with Magnum Equipment
Please make sure to go through these steps to make sure you have properly sized your system to
avoid damaging your battery. There are 4 ways of properly calculating the battery bank size for a
given system as outlined below:
1. Match Overcurrent Protection Device (Breaker Sizes)
∑
≥
   
∑
  
2. Match Inverter Surge Rating to Maximum Current Rating of Battery
∑
≥
   
∑
  
&
∑
≥
   
∑
  
3. Match Charge Controller to Battery Bank charge capacity
∑
≥
  
∑
 
4. Calculate the required battery bank capacity based on actual loads
∑
  
(

)
∑
   
(

)
𝑥 100% ≤ 80%
For the following battery bank size calculations, the below system assumptions apply:
 1 Magnum MS4448PAE Inverter
o Recommended External DC Breaker Size: 175A DC
o Nameplate Capacity: 4300 Watts continuous / 90A DC
o Surge Capacity: 7500 Watts for 5 seconds / 156A DC
o Chargers
 Capacity: 55A DC per Charger
 2 parallel chargers: 110A DC
1. Match Overcurrent Protection Device (Breaker Sizes):
 A Magnum MS4448PAE inverter requires externally obtained DC breaker.
Magnum recommends (1) 175A DC breaker
 The LFP-5 has a 125A breaker

(
125𝐴 + 125𝐴
)
≥
(

)
  
 (
 
175𝐴)
 The LFP-10 has a 150A breaker

(
150𝐴 + 150𝐴
)
≥
(

)
  
 (
 
175𝐴)
 A single eVault 18.5 has a 250A breaker

(
250𝐴
)
≥
(

)
  
 (
 
175𝐴)