Molten Metal Level Sensor
Non-contact sensor accurately detects molten metal level
- Operates either as "metal level low" or "metal level high" detector
- Detects change of metal level from one-half inch (13 mm) distance
- Resolution: ±0.04 inch (±1 mm) when sensor disk is 1/2 inch (13 mm) from molten metal
Applications
Paces operator additions of charge material for improved temperature control. Helps prevent dangerous overfilling of holding furnaces. Controls operation of automatic ingot loaders. Operates at temperatures up to 1400° F (760° C). Recommended for molten aluminum, zinc, tin, bismuth and similar metals.
How It Operates
Metal Level Low Mode - When molten metal is at desired level, green LED on signal light tower is on. When molten metal drops below desired level, control turns green light off, amber light on, and starts timer. If metal level does not return to pre-set height after adjustable time period, amber light turns off, flashing red light turns on, and signal horn sounds.
This mode of operation is especially useful to "pace" the operator by signalling exactly when ingot should be charged into melting furnace to minimize excessive temperature fluctuations caused by mistimed ingot additions.
Metal Level High Mode - When molten metal is below preset maximum level, green LED on signal light tower indicates furnace is ready to be refilled. When metal level reaches maximum height, green LED turns off and amber LED indicates furnace is filled. Optional: If metal level keeps rising, a pair of contact probes will turn on flashing red LED and loud signal horn indicating furnace has been overfilled.
Non-Contact Level Sensor Includes
A 5 inch diameter, high temperature rated, non-contact metal level sensor disk with radiant heat shield and cable connection box, heavy duty adjustable height sensor support bracket retractable for cleaning, detector electronics with potentiometer height setpoint adjustment, adjustable timer, flasher, dual or tri color bright LED signal light tower, and six feet of flexible conduit with low-loss cable for connecting level sensor to electronics enclosure.
Installation Notes
For maximum accuracy, sensor must be located no more than five feet from the electronics enclosure. Electronics enclosure is NEMA 3R rated and temperature inside enclosure must not exceed 150°F (65°C ); insulate enclosure from heat sources if necessary. Sensor relay output contact is SPDT (1 Form C). Sensor operates from 120 VAC power, 50/60 Hz. A 100+ dB signal horn is available as an option. Not recommended for molten magnesium or other fuming metals which emit metallic vapor that can conduct current between sensor disk and molten metal.
Video
In the above video, you can see the light bar positioned near the top of the machine. When the metal level drops to the point where an ingot can be added, the light bar turns amber. If an ingot is not added quickly enough, the light bar will turn red and be accompanied by a loud buzz.