Arc Furnaces

The RCTrms is ideal for arc furnace applications where accurate measurement of large load currents, in the 10kA to 100kA range, are required. Conductors are often large and the RCTrms can be supplied with coil lengths up to 5.0m if necessary. This offers an attractive alternative to current transformers, which are impractical and expensive.

In one such application the RCTrms is used to monitor three individual secondary currents of a  submerged arc furnace transformer.  The output of the RCTrms 4-20mA signal is connected to a PLC for continuous monitoring. The secondary windings of the transformer are connected via multiple contact clamps to the electrodes. Continuous monitoring of the secondary currents using the RCTrms is important to ensure that the secondary currents are all of the same magnitude.  An imbalance in the transformer secondary currents can be used to immediately identify a failure in the electrode contacts. Without current monitoring, the contact failure may not be identified and can lead to reduced transformer lifetime due to localized overheating of the transformer windings.