Fault Current Limiting Devices

The load side fault level is the same as the line side fault level or any other value lower than the calculated ohm s law prospective fault current.

Fault current limiting devices.

The fcl enables the substation to run with all three 33 11 kv transformers connected to the 11 kv bus bars with a fault level of 11 3 ka. This is another way of saying use a series rated system. Current limiting reactors are connected in series with the power system essentially to damp the short circuit fault current. Current limiting reactors are now widely used to control fault currents in both utility and industrial power systems.

Fault current limiting abb s fault current limiters are the efficient solution for short circuit current challenges in newly installed and existing electrical networks. Fault current limiters fcls are special power system devices used to mitigate and lower high short circuit currents to much more manageable levels for existing protection equipment like circuit breakers cbs. Use a current limiting overcurrent protective device ahead of the old switchboard. It is unknown how the downstream overcurrent protective device will perform in conditions where the fault current exceeds its interrupting rating even in conditions where a current limiting feeder is applied.

You check the equivalent rms let through current of a 1200a class l fuse and find it reduces the 45 119a available down to 21 000a. The i s limiter can be used in various applications providing a very high and fast fault current breaking capability at high operating currents. The term includes superconducting solid state and inductive devices. This can be determined through testing known as series rating but is not permitted for consideration within ul 508a.

The primary advantages of a current limiting reactor are. The growing energy demand and the need for stable power supply are some of the major challenges faced by consumers power producers and network operators. In a power transmission network without complete disconnection. During normal operation a continuous current flows through the reactor.

This fault current limiter was installed in uk power network s 33 11 kv substation in newhaven east sussex england in 2013.