A transmitter for use in a process control system has externally accessible actuators for permitting external adjustment of the zero and span (or full scale) settings of the transmitter. The transmitter has an explosion-proof housing which includes an interior chamber in which transmitter circuitry is located. Each of the actuators includes a movable magnet which operates a magnetic reed switch located within the interior chamber of the housing through a wall of the housing. Each of the magnets ...

A monitor of measurable environmental conditions, contained in a thin, watertight envelope with an electronic processing circuit, liquid crystal display, operating in the positive or negative mode and a two way r/f or infrared spectrum communication system. The monitor collects, stores and provides a readout of the information collected. The processing circuit has a programmable memory and the ability to monitor simultaneously multiple conditions.

A communicator for field instruments connected to a transmission line for transmitting electric signals from the field instruments to a host instrument. The communicator operates on electric power fed from an external power supply over the transmission line. The external power supply is arranged in the transmission line. Electric current consumed by the transmission line is set to a constant value.

A communicator for field instruments connected to a transmission line for transmitting electric signals from the field instruments to a host instrument. The communicator operates on electric power fed from an external power supply over the transmission line. The external power supply is arranged in the transmission line. Electric current consumed by the transmission line is set to a constant value.

Conversion circuitry for use in a process control system is adapted for coupling to a primary process control loop. Digital receiver circuitry in the conversion circuitry receives a digital signal transmitted over the primary process control loop from a field transmitter and responsively provides a digital output. A microprocessor receives the digital output and responsively provides a secondary loop control output. Secondary loop control circuitry for coupling to a secondary process control loo...

A telemetry system is described including a remote unit having a remote input unit coupled to a remote transmit unit. The remote input unit receives one or more sensor output signals and produces a sensor status signal dependent upon the sensor output signals. The sensor status signal alternates between a first state and a second state, wherein an amount of time the sensor status signal remains in the first state is dependent upon one of the sensor output signals. An amount of time the sensor st...

An apparatus for determining the unbalance of wheels mounted on a vehicle comprises at least one measuring rack for supporting a vehicle wheel, a sensor provided in the measuring rack for sensing vibrations caused by the unbalance and for issuing a sensor signal. A measurement/control unit generates unbalance signals from the source signals which represent the unbalance with respect to magnitude and direction. At least the unbalance magnitude is displayed at a display unit. A wireless signal tra...

A wireless sensor network for monitoring of a container includes a sensor disposed for monitoring of a container, at least one remote sensor interface, and a gateway. The sensor is configured to acquire data related to the container and communicate sensor data as a function of the acquired data. The remote sensor interface is configured to receive the sensor data communicated from the sensor and wirelessly transmit data relating to the received sensor data. The gateway is configured to receive d...

A telemetering system wherein a transmitting device responsive to an input signal derived from a sensor representing a metered variable, such as temperature or flow rate, is adapted to generate a corresponding direct-current signal. This signal is conveyed over a two-wire line to a receiving station through a terminal resistor across which a voltage signal is developed corresponding to the incoming current signal. The receiving station includes a DC power supply whose output is fed over the same...

The invention is primarily directed to sensor modules for mounting directly upon energized electrical power lines to monitor parameters associated with operation thereof, wherein the modules have a more compact lateral configuration than prior art modules designed for the same purpose. The modules include a first, cylindrical housing portion containing the sensing means and other electronic data processing and transmitting elements, and a second housing portion, affixed to the exterior of the fi...