Level – Point – Sigmahellas

POINT LEVEL MONITORING & CONTROL

The most common application for point level control is to monitor the maximum and minimum levels of a tank to prevent overflowing or reaching an empty level with one or two sensors that activate or deactivate a pump when the liquid reaches the critical level.

A variety of options for point level control are available.

Capacitive switches

Capacitive switches can detect both conductive and nonconductive objects such as water and other liquids, plastics, wood, glass and a variety of other materials without contact. Capacitive proximity switches are ideal for product detection because of their ability to detect nonconductive targets.
The capacitive switch is designed so that an electrostatic field is formed between the active electrode and the earth electrode. Any object entering this field will increase the capacitance. The increase in capacitance depends on the following factors:
The distance and position of the object in front of the active electrode
The dimensions of the object
The dielectric constant of the object
When the increase in capacitance is large enough, an oscillation is set up. This oscillation is detected by the evaluation circuit, which then changes the state of the output circuit. The switch can be installed vertically or horizontally to detect

the product level.

Capacitive switches that have been used successfully in many applications, are: M30 in plastic housing, push button setup, DC or AC switching output
M30 in metal housing for high temperature applications (up to 250C or 482 F), Switching output, DC M30 in plastic housing, potentiometer setup, DC or AC/DC switching output
M18 in plastic housing, potentiometer setup, DC or AC switching output

Low Profile (flat rectangular) with Easy Setup,plastic housing, Switching output, DC, Ideal for Sight Glass Applications.

LEDs provide visual indication of output status and Special mounting adapters are also available for the M30s, for easy installation/removal, etc.

mounting adapters

Ultrasonic sensors/switches

Ultrasonic sensors provide a cost effective sensing method with unique properties not possessed by other sensing technologies. By using a wide variety of ultrasonic transducers and several different frequency ranges, an ultrasonic sensor can be designed to solve many application problems that are cost prohibitive or simply cannot be solved by other sensors. Ultrasonic sensors continuously emit high frequency sound pulses inaudible to the human ear which travel away from the sensor, hit the surface of the target and are reflected back to the sensor. The sensor electronics measure the time taken by the signals to return after being reflected by the target surface.

Since the speed of sound is affected by air temperature, our ultrasonic sensors include a built-in temperature sensor. Level/distance measurements are automatically temperature compensated throughout the operating temperature range of the sensor.

Classic applications include proximity sensing, object presence or absence, obstacle detection for automated vehicles, distance measuring, level measuring, etc etc

highlights

Direct measuring value output in mm/cm or % via LED display
Temperature compensation for accurate measuring with fluctuating temperature
accuracy with temperature drift internal compensation, ± 1%
Numerical sensor setting via LED display for a complete pre-setting of the sensor
1 or 2 pnp or npn switching outputs for all controls
Analogue output 4-20 mA and 0-10 V for two signals in one device (optional), reverse polarity protection
Operating voltage 9-30 V for application in various supply networks
Additional teach-in-function for a traditional setting of detect points
Automatic synchronisation for simultaneous operation of up to ten sensors in confined spaces
Automatic switchover between current and voltage output for simple operation
Housing material brass sleeve, nickel-plated, plastic parts, PBT, TPU (stainless steel optional)
protection rating IP67
vibration & shock complies to IEC 60068-2-27

Different operating modes and device configurations enable our ultrasonic sensing systems to be used in most conceivable automation applications
detection ranges