Liquid Level Sensors Specifications

Help with Liquid Level Sensors specifications:

Device Classification


	Device Classification
	Your choices are...
	Sensor-Only		This includes sensors, transducers, and switches, whose output is meant for a processor, controller or data acquisition system. A display or user interface is typically not present.
	Instrument / Sensor System		An instrument or sensor system has more capability than a transducer. The unit may have a display and/or a user interface. If you desire a simple gauge, a locally programmable unit (stand-alone) or a controller / totalizer, choose this option.
	Level Gauge		Level gauges provide a direct, visual measurement of liquid volume. Because they provide a direct measure, there are no intermediate components that can provide a faulty reading.
	Search Logic:		All products with ANY of the selected attributes will be returned as matches. Leaving all boxes unchecked will not limit the search criteria for this question; products with all attribute options will be returned as matches.

	Level Measurement Type
	Your choices are...
	Continuous Level		Device measures level within a specified range, output gives a continuous reading of level.
	Point Level / Multi-Point Levels		Devices mark a specific level and are generally used as a high alarm or switch. Multiple-point sensors can also be integrated in one device to add a low alarm, or to serve as a stepped version of a continuous level.
	Search Logic:		All products with ANY of the selected attributes will be returned as matches. Leaving all boxes unchecked will not limit the search criteria for this question; products with all attribute options will be returned as matches.

	Number of Switch Points		The level sensing device has a series of switches along the probe. When the material is present this causes the switch to activate.
	Search Logic:		User may specify either, both, or neither of the "At Least" and "No More Than" values. Products returned as matches will meet all specified criteria.

	Measuring Range:		The level range that devices can measure.
	Search Logic:		User may specify either, both, or neither of the limits in a "From - To" range; when both are specified, matching products will cover entire range. Products returned as matches will meet all specified criteria.

	Maximum Operating Pressure		Maximum pressure environment device is rated for.
	Search Logic:		All matching products will have a value greater than or equal to the specified value.

	Material Temperature Range		Maximum material temperature device is rated for.
	Search Logic:		User may specify either, both, or neither of the "At Least" and "No More Than" values. Products returned as matches will meet all specified criteria.

	Liquid Specific Gravity		Maximum specific gravity of liquid being monitored.
	Search Logic:		All matching products will have a value less than or equal to the specified value.

	Field Adjustable Measurement Ranges?		Different ranges can be selected while devices are in the field.
	Search Logic:		"Required" and "Must Not Have" criteria limit returned matches as specified. Products with optional attributes will be returned for either choice.

Output



	Your choices are...
	Analog Voltage		The output is an analog voltage signal.
	Analog Current		Output signal is a current value indicating level; include transmitter outputs such as 4-20mA, 0-50 mA, etc.
	Frequency / Modulated Frequency		Frequency or modulated frequency output (e.g., sine wave, pulse train, AM, FM, etc.)
	Search Logic:		All products with ANY of the selected attributes will be returned as matches. Leaving all boxes unchecked will not limit the search criteria for this question; products with all attribute options will be returned as matches.

Meter Technology


	Meter Technology
	Your choices are...
	Differential Pressure Sensors		Differential pressure sensors measure head pressure in a vessel based on the height of the media.
	Ultrasonic / Sonic		Ultrasonic or sonic devices measure the length of time it takes for a reflected sound wave to return to a transducer. Transmitted time is proportional to level.
	Radar / Microwave		Device emits a microwave pulse toward process material; the pulse is reflected back by surface of material and picked up by receiver. Level is inferred from the time of flight.
	Optical		Optical devices use optic sensors and the principle of optical reflection to detect the presence or absence of fluid. Typically, light emitting diodes (LEDs) are used as the light source.
	Pressure Membrane		Pressure membrane meters have a pressure-sensitive switch. They transmit pressure to an internal sensor via an organic or thin-metal membrane.
	Electrical Conductivity / Resistance		Electrical conductivity or resistance-based devices use a low-voltage power source applied across separate electrodes. A conductive liquid which contacts both probes completes a conductive circuit.
	Capacitive / RF Admittance		Capacitive or RF admittance devices use a radio frequency (RF) technique that is based on differing dielectric constants. The impedance from the RF signals changes whenever the material approaches the sensing region.
	Air Bubbler		Air bubblers feed a gas (usually air) at constant volumetric rate through a bubble tube submerged in a liquid. The amount of pressure needed to force the bubble from the bottom of the tube is equal to the hydrostatic pressure at that point.
	Mechanical / Magnetic Floats		Mechanical devices or magnetic floats use sealed reed switches in a stem with a permanent magnet installed in the float. As the float rises or falls, the switch is activated.
	Rotation Paddle		Device uses a small electric motor drives a paddle that rotates freely in the absence of material. When the paddle is impeded by material, the motor senses this and typically triggers a switch or switches.
	Radio Frequency		Radio frequency (RF) devices emit a high-frequency/low-power radio signal from a probe. When the material contacts the probe, the bridge becomes unbalanced and a comparing circuit realizes the change. This causes a relay output to change state.
	Vibrating / Tuning Fork		Tuning forks use various technologies (typically piezoelectric) to vibrate a probe and then constantly monitor the presence or absence of that vibration.
	Other		Unlisted, specialized, or proprietary technology.
	Search Logic:		All products with ANY of the selected attributes will be returned as matches. Leaving all boxes unchecked will not limit the search criteria for this question; products with all attribute options will be returned as matches.

More Specs


	Communication Interface
	Your choices are...
	Serial Interface		Serial interfaces use a serial communication protocol such as universal serial bus (USB), RS232, or RS485.
	Parallel Interface		Parallel interfaces use a parallel communication protocol such as general-purpose interface bus (GPIB).
	Other Interface Type		Devices use other, unlisted communication interfaces (e.g., modems, RF transmitters).
	Search Logic:		All products with ANY of the selected attributes will be returned as matches. Leaving all boxes unchecked will not limit the search criteria for this question; products with all attribute options will be returned as matches.

	Mounting
	Your choices are...
	Side Mount		The device mounts on the side of the vessel which contains the media to measure.
	Top Mount		The device mounts on top of the vessel which contains the media to measure.
	Bottom Mount		The device mounts at the bottom of the vessel which contains the media to measure.
	Search Logic:		All products with ANY of the selected attributes will be returned as matches. Leaving all boxes unchecked will not limit the search criteria for this question; products with all attribute options will be returned as matches.

	Display:
	Your choices are...
	Visual or Audio Output		The display has a non-electrical visual indicator such as simple float, or an audible click.
	Analog Meter / Indicator		The display has an analog meter (typically with a needle), or uses LED indicators.
	Digital Readouts		The device displays numerical or application-specific readouts.
	Video Display Terminal (VDT)		Video display terminals (VDT) include cathode ray tubes (CRT) and flat panel displays (FPD).
	Search Logic:		All products with ANY of the selected attributes will be returned as matches. Leaving all boxes unchecked will not limit the search criteria for this question; products with all attribute options will be returned as matches.

	User Interface:
	Your choices are...
	Analog Front Panel		The interface has analog inputs such as potentiometers, dials, or switches.
	Digital Front Panel		The device is set up or programmed through a digital front panel.
	Computer Controllable		The device can be controlled remotely via a computer interface.
	Search Logic:		All products with ANY of the selected attributes will be returned as matches. Leaving all boxes unchecked will not limit the search criteria for this question; products with all attribute options will be returned as matches.

	Features
	Your choices are...
	Rated for Sanitary Applications		Devices are rated for sanitary applications such as those found in the pharmaceutical and food processing industries.
	Handles Slurries / Suspended Solids		Devices can handle slurries or suspended solids such as sewage and wastewater.
	Built-in Alarm / Indicator		Devices have a built-in audible or visual alarm that is more than a switch or relay closure.
	Programmable		Devices can be programmed for different ranges, materials, outputs, etc.
	Recorder / Totalizer Functions		Devices are data loggers which record/totalize and integrate measured values.
	Controller Functions		Devices have or take sensor inputs, provide control functions (e.g., limits, PID, logic), and output a control signal.
	Search Logic:		All products with ANY of the selected attributes will be returned as matches. Leaving all boxes unchecked will not limit the search criteria for this question; products with all attribute options will be returned as matches.