Contact Pad - Rogowski Coil (High Current CT) - Furnace Monitoring

Introduction
The System was designed to provide a accurate simultaneous measurement of 
the individual Contact Pad kilo amps & summated electrode current
This has not been possible in the past.
H.V. Test cc in South Africa have developed a unique system for the 
measurement of these currents.
A number of these systems have been successfully operating on submerged arc 
closed top furnaces since 1998
System Goal
The measurement of the individual electrode contact pad currents using 
current transducers, signal processing, isolation and a monitoring system
The system can be integrated into the existing PLC furnace control system
The goal is to monitor each contact pad to determine when overloading 
& under loading occurs due to poor contact or green electrode problems.
The System can record trends predicting contact pad problems, electrode 
slipping changes and possible green electrode changes
The System
Each set of bustubes is monitored by the system and individual signals are transferred to the control room. The signals can be incorporated in the existing monitoring and recording system or a dedicated PC. The PC will present a visual picture of the furnace, the contact pads and the electrodes. When a Contact Pad is been overloaded or underloaded the screen will alarm red or green together with a audible alarm.
Next to each contact shoe, the current in KA will be reflected together with the phase current/transformer as well as the victory summated electrode current
Should the current on the contact pads vary dramatically this could be an indication of:
Poor Contact pad service pressure problems
Overslipping of the electrode and that a green electrode is eminent
Indication of furnace mix problems
Electrode Breakages
Secondary Transformer winding overloading
Cooling water temparature problems
Electrode casing problems
Cavitation in the electrode
Conclusion
We believe that this monitoring system will provide the furnace operators with valuable information allowing optimised operation of the furnace