Can you verify if this is ok?
Total load on the system is approximately 200A
It will be fed by a 3 phase Delta 480V 75KVA transformer to a 208/120 Y electrical panel 225A main breaker.
The transformer is rated at 90A on the primary side and 208A on the secondary side using maths below
75KVA/(1.73x480V) = 90A
75KVA/(1.73X208) = 208A
480V Main Service to 100A Service Disconnect and to transformer wired with ((3) #1 and (1) #8 gnd) and then from transformer 75KVA wired with ((4) 250 KCMIL & (1) #2 gnd) to 225A electrical main breaker. There will be also a 225A rated meter connected from the electrical panel with (4) 250KCmil & (1) #2 gnd.
According to article 450, I should cover my overcurrent protection on the primary and secondary side and also my wire size accordingly to article 240. right? Secondary ground is based on table 250.66
Total load on the system is approximately 200A
It will be fed by a 3 phase Delta 480V 75KVA transformer to a 208/120 Y electrical panel 225A main breaker.
The transformer is rated at 90A on the primary side and 208A on the secondary side using maths below
75KVA/(1.73x480V) = 90A
75KVA/(1.73X208) = 208A
480V Main Service to 100A Service Disconnect and to transformer wired with ((3) #1 and (1) #8 gnd) and then from transformer 75KVA wired with ((4) 250 KCMIL & (1) #2 gnd) to 225A electrical main breaker. There will be also a 225A rated meter connected from the electrical panel with (4) 250KCmil & (1) #2 gnd.
According to article 450, I should cover my overcurrent protection on the primary and secondary side and also my wire size accordingly to article 240. right? Secondary ground is based on table 250.66
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