Abstract: A monitoring port assembly for a fluid treatment system, such as for use in an ultra-violet water treatment system. The port assembly comprises a sensor port cup having a port for access to an interior of the fluid treatment vessel. The port is offset from the central axis of the sensor port cup. A cylindrical body, having an offset through-hole to receive a sensor assembly, is disposed within the sensor port cup for rotational movement about the central longitudinal axis between an operational position where the offset through-hole is aligned and coincident with the port, and a servicing position where the offset through-hole is displaced relative to the port. Sensors can be safely and conveniently removed from or installed into a port in the fluid treatment vessel by rotating the cylindrical body from the servicing to the operational position.

Abstract: A fluid treatment system in which the fluid to be treated is irradiated with ultraviolet light (UV). The system includes a sensor with capabilities for detecting multiple fluid treatment parameters, such as UV intensity level and fluid flow. The sensor contains a combination of a UV sensing means such as a photodiode, a flow sensing means such as a vibration sensitive microphone, and associated electronics for processing and transmitting data pertaining to the fluid treatment parameters. The system can also include or alternatively include an intelligent driver that powers a UV lamp and has the novel capabilities to receive, process, respond to, and display multiple fluid treatment parameter signals from one or more sensors without the need for additional signal processing and/or control devices. Specifically, in a preferred embodiment, the power being delivered to the UV lamp will be adjusted as warranted by the intelligent driver's analysis of at least one fluid treatment parameter, such as flow condition.

Abstract: An apparatus for starting and operating UV lamps, comprises an AC line powered circuit and a UV lamp. The circuit has a variable frequency AC source, providing AC current to the UV lamp and a ballasting inductor, connected in series with the UV lamp. The inductor and the lamp form a nonresonant coupling sub-circuit where a flow of current from the AC source through the UV lamp is limited by the ballasting inductor. The circuit does not develop dangerously high output voltages if the UV lamp is disconnected or burnt out, as would be the case with resonant output circuits, unless additional circuit protection was implemented. The impedance of the ballast inductor varies with the current frequency, enabling it to act as a current control element with changes in the output frequency. An open loop control circuit of the present invention maintains the lamp current at a relatively constant level without the complexity imposed by closed loop current control methods.