Current Transformers
APPLICATION
Low voltage current transformers are intended for supplying meas-uring instruments and protection circuits of electrical power devices with a maximum operating voltage of 0.72 kV and frequency
of 50 Hz (or 60 Hz after prior arrangement with the manufac-turer). Transformers of power utility installations. The transformers are manufactured for secondary currents 1A and 5A. The range of primary currents depends on the transformer and can range from 1 A up to 6,000 A.
OPERATING CONDITIONS
The transformers are designed for operation in indoor equip-ment in climatic conditions: temperate (N3) or tropical (T3). The long–term thermal rated current and limits of deviations of these transformers correspond to an extended current range of 120% of Ipn within the ambient temperature range from 248 K (-25°C) to 328 K (+55°C). It is possible to produce some transformers with a 150% or 200% current range by special arrangement with the manufacturer.
DESIGN
The low voltage current transformers are single-phase, low power transformers, operating in quasi short-circuit conditions and trans-forming the current flowing through the primary circuit to the current in the secondary circuit with a level of accuracy specified in relevant standards. Their insulation class is E or A. The windings of the cur-rent transformers are enclosed in the housings made of heat and fire resistant material.
The current transformers are produced for different types of primary circuits: busbar or cable. The range of primary currents is from 1 A up
to 6000 A. Transformer types: IMW, IMP, IMS, IMR2 and ISW (with the exception of ISWc) have offer the option of a sealing cover for secondary termianals. Transformers are permanently marked with the rated ratio on both sides of the casing. They have slides allow-ing assembly to the base and screws or holder for mounting on the current circuit.
MOUNTING
Low voltage current transformers can be mounted on:
- current busbars
- TS35 mounting busbars
- solid cables or cores of multicore cables
- plates
The current transformer can be mounted in any position. In order to mount a given type of transformer it should be drawn onto the busbar, next it should be fastened with the holders or mount-ing bolts to be found on both sides of the transformer. Mounting of the transformer on a plate, depending on the type, is made possible by two or four slides with which the device is furnished. A special base allows mounting on the TS35 mounting busbar. When mounting a transformer equipped with its own busbar, it should be fastened to the current circuit with the supplied bolt termianals with which the transformer busbar is furnished.
Low voltage current transformers cannot be used as support elements for current busbars (they cannot replace support insula-tors).
 Download the Low Voltage Current Transformers catalog in *.pdf format
Download the Electronic Products and Relays catalog in *.pdf format
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