Current transformer of PT line, based on steel tape wound toroidal core, current transformers of PPT line, based on nanocrystalline tape wound toroidal core and current sensors of PS line, based on high permeability ferrite toroidal cores, are used for galvanic separated AC measurements.
The primary winding is usally set up of one put-through conducting wire, which leads through the inner transformer opening. The secondary winding is buld-in. With the change of primary winding put-through number, you can change the conversion ratio and its current range.
The specification of linearity, current range and conversion slope are valid with the recommended resistor applied to the secondary winding. If needed, it is possible to change the value of resisor significantly and thereby adjust the conversion slope or maximum current. (However, too large load resistance may impair the linearity of the conversion.)
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