Abstract: An apparatus for optically connecting at least two independent half-duplex networks. The apparatus receives electrical signals from a first network, converts these signals to optical signals, and then transmits the optical signals along optical fiber to another apparatus. This apparatus converts the optical signals it receives to electrical signals and transmits the signals to the second network. The apparatus controls the flow signals to and from the networks and optical fibers without any external control signals.

Abstract: The present invention pertains to a system for controlling a fume hood with a face. The system comprises a device for controlling air flow through the fume hood based on air flow face velocity. The controlling device has a device for measuring pressure at the face of the fume hood which produces a signal corresponding to the pressure. Additionally, the system comprises a controller. The controller is remote from the fume hood controlling device but in communication with the controlling device. The present invention also pertains to a system for controlling a fume hood having a face. The system comprises a pitot tube assembly for determining a desired face velocity. The pitot tube produces a pitot signal corresponding to the face velocity. The system comprises a device for converting the pitot signal into a face velocity signal. The converting device is connected to the pitot tube. Additionally, the system comprises a processor for controlling air flow through the fume hood based on the face velocity.

Abstract: The present invention pertains to a system for controlling a fume hood with a face. The system comprises a device for controlling air flow through the fume hood based on air flow face velocity. The controlling device has a device for measuring pressure at the face of the fume hood which produces a signal corresponding to the pressure. Additionally, the system comprises a controller. The controller is remote from the fume hood controlling device but in communication with the controlling device. The present invention also pertains to a system for controlling a fume hood having a face. The system comprises a pitot tube assembly for determining a desired face velocity. The pitot tube produces a pitot signal corresponding to the face velocity. The system comprises a device for converting the pitot signal into a face velocity signal. The converting device is connected to the pitot tube. Additionally, the system comprises a processor for controlling air flow through the fume hood based on the face velocity.

Abstract: A system for maintaining a desired air flow through a fume hood having a sash. The system comprises a mechanism for controlling air flow through the fume hood based on at least one gain. The system is also comprised of a mechanism for automatically tuning the gain connected to the controlling mechanism. Additionally, the system is comprised of a mechanism for manually inputting information to the tuning mechanism so the tuning mechanism automatically provides a desired gain to the controlling mechanism based on information received from the input mechanism. Additionally, the present invention pertains to a qualitative tuning system for a processor. The present invention also pertains to a method for controlling air flow through a fume hood with a sash. The method comprises the steps of providing information concerning flow of air through the fume hood to a processor. Then, there is the step of manually inputting information concerning gain into a qualitative tuning system connected to the processor.

Abstract: A system for controlling laboratories having fume hoods comprising a network along which information is carried. The system is also comprised of a controller in contact with the network for receiving information from and providing information to the network. Additionally, the system is comprised of means for sensing a laboratory's state. The sensing means is disposed in each laboratory. There is additionally a microprocessor disposed in each laboratory for receiving information concerning the laboratory from the respective sensing means and the controller in order to maintain the laboratory in a predetermined state, and to provide information about the laboratory to the controller.

Abstract: An apparatus for optically connecting at least two independent half-duplex networks. The apparatus receives electrical signals from a first network, converts these signals to optical signals, and then transmits the optical signals along optical fiber to another apparatus. This apparatus converts the optical signals it receives to electrical signals and transmits the signals to the second network. The apparatus controls the flow signals to and from the networks and optical fibers without any external control signals.

Abstract: An apparatus for optically connecting at least two independent half-duplex networks. The apparatus receives electrical signals from a first network, converts these signals to optical signals, and then transmits the optical signals along optical fiber to another apparatus. This apparatus converts the optical signals it receives to electrical signals and transmits the signals to the second network. The apparatus controls the flow signals to and from the networks and optical fibers without any external control signals.