MI 2893 / MI 2892 / MI 2885
Connection setup
152
Figure 129: Current clamps selection for indirect current measurement
Over-dimensioned current transformer
Installed current transformers on the field are usually over-dimensioned for “possibility to add new
loads in future”. In that case current in primary transformer can be less than 10% of rated transformer
current. For such cases it is recommended to select 10% current range as shown on figure below.
Figure 130: Selecting 10% of current clamps range
Note that if we want to perform direct current measure with 5 A clamps (secondary current
measurement), primary transformer ratio should be set to 5 A : 5 A.
WARNINGS!
The secondary winding of a current transformer must not be open when it is on a live circuit.
An open secondary circuit can result in dangerously high voltage across the terminals.