Electrode configuration for LiMCA

An apparatus for measuring particles in molten metal with a Liquid Metal Cleanliness Analyzer (LiMCA), having electrically insulating wall means having a passage formed therein for passage of the molten metal and particles, an inside electrode inserted in the molten metal inside the wall means, comprising:

• (a) a first and a second outside electrode inserted into the molten metal outside the wall means on either side of the inside electrode, to form a common plane with the inside electrode;
• (b) a current source-connected to the first and a second outside electrodes for feeding equal current directly from the current source to the first and the second electrodes, which current passes with the traveling molten metal through the passage to the inside electrode to create symmetrical current loops between each of the first and the second outside electrodes and the inside electrode and generates wanted pulse signals;
• (c) detection means connected to the first and the second outside electrodes and the inside electrode, for detecting wanted pulse signals generated by the current loops due to travel of particles through the passage, and for canceling electromagnetic noise that affects equally but in an opposite manner each of the current loops;
• (d) a circuit for adding the wanted pulse sianals generated by each current loop to at least reduce the electromagnetic noise;
• and
• (e) computing means for subjecting the wanted pulse signals to analysis to measure particles in the molten metal based on said wanted pulse signals.