Solid-core current transformer products in the UCT class of sensors from Magnelab have better than a one percent accuracy and a less than one degree phase angle.
Output is controlled by a precision resistor fixed at the industry standard of 0.333 Volt AC. The rugged epoxy encapsulated construction comes with eight feet twisted leads.
Revenue Grade version available with 0.5% linearity with less than 0.26° phase shift. See SPEC sheet for more details.
For a solid-core current sensor with a 5 amp output, see the MGS solid-core current sensor.