What is a current transformer?
A current transformer is a type of transformer that is used to measure AC. It produces a current in its secondary which is proportional to the current in its primary.
Open and Dry type
Primary (normally high voltage) winding on inner side and thin wires with high resistance.
Secondary (normally low voltage) winding normally on inner side with very low resistance.
Power range: 110VA-3KVA
Voltage range: Any input and output voltage
Frequency range: 50Hz, 60Hz, 50/60Hz & 400Hz
a. Current transformers are used extensively for measuring current and monitoring the operation of the power grid.
b. Along with voltage leads, revenue-grade CTs drive the electrical utility’s watt-hour meter on virtually every building with three-phase services greater than 200 amperes.
c. Current transformers can be mounted on the low voltage or high voltage leads of a power transformer. Sometimes a section of a bus bar can be removed to replace a current transformer.
d. Often, multiple CTs are installed as a stack for various uses. For example, protection devices and revenue metering may use separate CTs to provide isolation between metering and protection circuits and allows current transformers with different characteristics to be used for the devices.
Open and enclosed transformers with different IP ratings and mounting are available.
Available values in market
Availability by power: 110-300V, 1.5KV, 3KV
Availability by voltage:
Primary- 25A, 40A, 50A, 200A, 250A, 300A, 1.5KA, 3KA, 4KA
Secondary-50mA-95A, 50mA-120A, 5A, 1A-50A, 50-1500A,
Availability by frequency: 50/60Hz