For refinery engineers, chemical plant operators, power generation teams, boiler and steam system designers, and EPC specifiers who need high-pressure, high-temperature point-level protection with mechanical certainty, the Omnitrol 666 / 668 (C) delivers compact, chamber-mounted displacer switching engineered for extreme duty environments.
Unlike electronic switches that can drift or fail under heat, vibration, and pressure cycling, the Omnitrol 666 / 668 (C) uses proven mechanical displacer technology, welded “C”-style chambers, and field-proven magnetic snap-action switching to ensure fail-safe level protection for liquids, including low-specific-gravity hydrocarbons, solvents, and steam condensate.
Ideal where space is limited, reliability is critical, and electronics are not preferred, this model provides a field-proven solution for pressurized vessels, blow-down drums, steam systems, condensate pots, and hazardous media tanks.
Provides excellent performance on low-SG liquids and high-pressure services where space is limited for installation.
Proven reliability in harsh environments with no electronics required—ideal for safety systems, utilities, and critical applications.
Full isolation from tank internals ensures safe operation in pressurized or corrosive media without internal penetration.
Safe deployment in refineries, chemical plants, and hazardous vapor environments with UL and CSA certified explosion-proof housings.
Flexibility for outdoor, classified, and corrosive areas while meeting electrical safety codes for Weather-proof and Explosion-proof configurations.
Ensures process protection for high/low level alarms, pump shutdown, and safety interlocks through mechanical snap-switch actuation.
Single-point mechanical displacer level switch
Short welded “C” body
Liquid level, high or low alarm / trip
Graphite standard; stainless steel optional
External side & bottom connections (1” NPT std; flange/weld options)
Weather-resistant, Explosion-proof /Vapor Proof/Rain Tight
Designed for high-pressure / high-temp process service (See specific datasheet for class & limits per model)
Field-proven magnetic coupling + snap switch output
Single setpoint
If you have questions not covered here, please contact the Cognesense support team for assistance.
Contact Us ↵Mechanical displacer switches offer fail-safe action, no drift, and immunity to heat and EMI — ideal for safety and steam service.
Hydrocarbons, condensate, light solvents, process water, and most refinery/chemical liquids — including low-specific-gravity fluids.
No — the 666/668(C) is a single-point switch.
Yes — all mechanical components are external, enabling safe isolation and maintenance.
Yes — its pressure-rated chamber and mechanical design make it ideal for steam drums, blow-down systems, and condensate vessels.
The displacer system is engineered to sense very small density changes, outperforming floats and ultrasonic devices in LPG/NGL and solvent service.
The Omnitrol 666/668(C) chamber-mounted level switches deliver rugged mechanical reliability, compact pressure-rated construction, and superior performance in low-SG and hazardous service environments. When safety, simplicity, and durability matter most, especially on pressurized vessels, this switch offers proven protection without electronics, drift, or complexity.