Custom Search
|
|
|
||
 TABLE 9-1.
FULL-LOAD LINE AMPERES FOR THREE-PHASE* TRANSFORMERS OR LOADS
For single-phase transformers or loads , multiply the above three-phase values
by 1.73.
Example 1: A 5 kVA single-phase transformer has a secondary line current of
12 x 1.73 = 20.8 amperes at 240 V when operating at full load.
Example 2: Assume the load to be metered is fed by a 500 kVa transformer at
208 volts on the secondary. If the load is metered on the secondary side of
the transformer, the ammeter will see a max current of 1,388 amps. Thus a
current transformer with a ratio of 400 to 1 (2,000/5) should be used.
9-29
|
 
|
|
|
||
