Current Tranformers

 
The term current transformer was alien to me until I witnessed the testing of the UPS system in All Asia Broadcast Centre. They were performing a primary and secondary injection, where I was asked if I knew the difference between these to injection methods. I was clueless and then briefed. The explanation was somewhere along the lines of the main line being the primary and some sort of device that makes it easy to measure as the secondary, in this case a current transformer (CT).
So what is a CT? A current transformer is a type of "instrument transformer" that is designed to provide a current in its secondary which is accurately proportional to the current flowing in its primary.
The current transformers used with the Wattnode transducers produce a 333 mV alternating voltage when the rated current is measured (either 30A, or 50A). The OSI power transducers employ CT's that produce 5V output at rated value.
The current transformers used with the Wattnode transducers produce a 333 mV alternating voltage when the rated current is measured (either 30A, or 50A). The OSI power transducers employ CT's that produce 5V output at rated value.
Current transformers are designed to produce either an alternating current or alternating voltage proportional to the current being measured. Current transformers measure power flow and provide electrical inputs to power transformers and instruments. Current transformers produce an alternating current (or voltage) that is proportional to the measured current.
Insulation voltage represents the maximum insulation that current transformers provide when connected to a power source. Accuracy is the degree of certainty with which the measured current agrees with the ideal value. Burden is the maximum load that devices can support while operating within their accuracy ratings. Typically, burden is expressed in volt-amperes (VA), the product of the voltage applied to a circuit and the current.