Liquid Level Float Switches for Active Heated Humidifiers, Ventilators, Autoclaves and Steam Sterilizers
Active heated humidifiers, such as those used in ventilators and high flow respirators, heat water in small chambers so that the vapor is mixed into the moving air as it is passed into the patient.
A single level float switch may be used to protect the heater against burning out if water levels drop too low. A multi-level float switch can be used to maintain proper levels, so that water does not get drawn into a patient’s airway.
A thermal sensor can be incorporated into the float switch to monitor the temperature and reduce tank intrusion and assembly costs. Wiring harnesses and tank sub-assemblies can also be incorporated into the design.
Madison Company designs and manufactures stainless steel float switches that meet the required specifications for sterilizers, autoclaves, and other critical parts washers.
Madison switches are a dependable part of the water supply that feeds steam to autoclave cabinets. Through a hard-piped connection, a pressure tank is filled with water to cover the heating elements and generate steam (Fig. 1, right).
As the water level drops, a low-level float switch or sensor is used to trigger a refilling cycle. As the water level rises, an upper-level float or sensor is used to indicate that the water level is sufficient to generate more steam (Fig. 2, left).
The water is heated under pressure of 15psi or greater, to create steam at or above 225°F / 121°C, which is critical for sterilization in autoclaves and steam generators. Madison SS float switches exceed these specifications & they are rated to temperatures of 485°F/250°C and pressures up to 300psi.