A method of measuring liquid level in a tank. An electromechanical liquid level gauge (ESG) is provided including a processor, a displacer suspended on a wire from a grooved drum having a servo motor coupled thereto to rotate the drum for balancing the displacer. A change in liquid level causes a change in a counterforce to move the ESG out of balance. The processor monitors a torque sensor output, and controls movement of the motor using a programmed apparent weight (AW) setpoint to raise or lower the displacer based on an AW derived from the torque. An associated memory stores a density compensated fixed immersion depth level gauging algorithm. The algorithm implements obtaining a density reading for the liquid, continuously corrects an immersion depth of the displacer for changes in density to provide an essentially fixed immersion depth, and calculates the liquid level from the density reading and immersion depth.

A method includes measuring tensions on a measuring wire coupled to a displacer of a servo gauge. The servo gauge is configured to raise and lower the displacer using a drum around which the measuring wire is wound. Different measured tensions are associated with different segments of the measuring wire. The method also includes calculating or adjusting a measurement associated with material in a tank using the measured tensions to account for a change in a length of the measuring wire. Calculating or adjusting the measurement could include calculating one or more first length adjustments for one or more segments of the measuring wire that are wound around the drum, calculating one or more second length adjustments for one or more other segments of the measuring wire that are unwound from the drum, and combining the first and second length adjustments to identify a final length adjustment.

A floatable flood detector has a watertight housing that carries internally a wireless transmitter and a fluid sensor. In the presence of sensed fluid, an alarm message can be transmitted by the transmitter to a displaced monitoring unit. The sensor has a portion exposed to the fluid of interest outside of the housing. The antenna is carried, at least at a fluid level, relative to the floating housing.

Technology relating to a sump pump monitor is provided herein. A sump pump monitor includes a water level sensor to measure a level of water in a pit of the sump pump, an overflow sensor to detect whether an overflow of the water is present in the pit of the sump pump, and a power monitor to monitor electric power delivered to the sump pump. The power monitor is also to transmit one or more signals indicative of an operational issue associated with the sump pump based on the level of the water, the overflow of the water, and the electric power.

A level gauge system for mounting on a roof of a semi-closed storage tank includes an automatic tank level gauge for determining a level reading for a liquid including at least one liquid component in the tank. A processor includes a memory storing pressure correction factors or a pressure correction factor equation for correcting the level reading for a measured gas pressure above the liquid in the tank. The processor is programmed for implementing choosing a selected pressure correction factor from the pressure correction factors or the equation based on a received current gas pressure above, and applying the selected pressure correction factor for automatically correcting the level reading provided by the tank level gauge to generate a corrected level reading which compensates for the current gas pressure above effects on the roof and on the level gauge.

A device for measuring the level of a material (e.g., a liquid) in a tank is disclosed. An example device includes a non-buoyant flexible member and a plurality of sensor nodes distributed along the length of the flexible member. The sensor nodes are configured to indicate a change in orientation. A buoyant float provides a generally U-shape configuration for the flexible member, and causes an increasing number of the sensing nodes to depart from a substantially vertical orientation as the level of the material rises within the storage tank. A monitor is configured to monitor a signal indicating the change in orientation of the sensor nodes. As such, the device may be implemented to conveniently and accurately measure the liquid level in the tank.

An automatic hysteresis compensated method of level measuring a liquid in a tank includes providing an electromechanical liquid level gauge including a controller with a processor, a displacer on a wire from a measuring drum with a motor, where the processor controls a movement of the motor and executes a level gauging algorithm. A measured force displacer position (FS) profile is provided including a move-down FS curve determining Fd, Sd corresponding to a displacer center when moving down and a move-up FS curve to determine Fu, Su corresponding the displacer center when moving up. The algorithm provided a time derivative of F is essentially zero, initiates performing a down/up dip of the displacer moving the displacer down/up to below/above the liquid level, then moving the displacer up/down passing Su/Sd, then moving the displacer to return to Sd/Su, and determining the current liquid level from Fd/Fu upon the return to Sd/Su.

A system for monitoring a floating roof of a liquid storage tank and a method for use of the system are described. The system includes linear position measuring devices to determine the vertical location and orientation of the floating roof within the storage tank and one or more transmitters to relay such information to a monitoring, recording, or control device, or to a remote computer network location. Typically, three measuring devices are used, positioned at or near the top of the storage tank and generally equally spaced around the perimeter of the tank. The system and method are useful to monitor the position and inclination of a liquid storage tank floating roof, such as may be used in the petrochemical, chemical and other industries where such storage tanks are in use.

A micrometer system and water holding cup and related for use in connection with a hydrostatic level-measuring system for measuring with precision, a level normal to gravitation of physical surfaces, the micrometer system comprising: a micrometer; an elongated micrometer probe tip at a lower extremity of the micrometer; a micrometer dial for extending and retracting the probe tip in response to a dialing thereof; a micrometer alignment section fixed to the micrometer, and a substantially rigid support structure for supporting the a micrometer alignment section at a fixed height above the physical surfaces when a footing of the support structure is rested upon the physical surfaces. The cup comprises mirroring on a bottom surface thereof; at least one reference feature on the mirroring surface for providing to a user, a visual reference for at least one micrometer grade marker reflected by the mirroring surface, for dialing a micrometer.

A toilet monitor uses a toilet tank water level sensor producing a toilet tank water level measurement signal. A processor detects rate of change of the measurement signal and conditionally produce a responsive actuation signal in response to the detected rate of change. A transducer connected to receive the actuation signal and transmit information, provide a humanly-perceptible indication, generate a data log and/or control an electronic water supply valve.