Current and voltage transformer
a) Voltage transformer Voltage transformers have only one iron core with a secondary winding connected. If an open delta circuit is necessary, additional winding can be provided for single-pole isolated transformers. For single pole insulated transformers, the end of the primary coil is grounded as “N” inside the secondary terminal box and must not be removed during operation b) Current transformer The current transformer is designed to transform the primary rated current flowing through the primary coil. The secondary coil must generally be short-circuited at all times, otherwise dangerous high voltages may occur at the secondary terminals. Secondary connected devices are connected in series. Current transformers may be equipped with one or more independent magnetic cores with equal or different characteristics for measurement, metering and/or protection purposes.
“Transformers convert high currents or voltages into measurable and uniform currents or voltages. These are then proportional and phased to the primary signal. They are intended to supply electrical measuring instruments, meters, relays or other electrical devices. Furthermore, the The connected measurement and protection are electrically isolated against live parts.