TEMPERATURE SWITCHES AND TEMPERATURE SENSORS
- Construction equipment
- Agricultural machinery
- Utility vehicles
- Hydraulic power-train control systems
- Mechanical- and plant engineering
- HVAC systems
- Fuel cells
BEDIA Motorentechnik offers a great variety of different temperature sensors for a number of applications. The product line-up ranges from high-performance electromechanical switches to screw-in resistors to high-precision electronical switches and sensors. A wide range of housing options and connectors can be provided. The robust and compact construction of BEDIA temperature sensors makes them the optimal solution in various fields of application like commercial vehicles, engines, power-train control systems, wind power, compressors as well as construction and agricultural equipment.
Bimetal Temperature Switches
These high-power bimetal operated temperature switches are available either with normally closed (NC) or normally open (NO) contact configuration.
The robust round metal enclosure accommodates a resilient preloading disk, a bimetal disk and a silver contact. The compact switch system is covered by means of a plate which also carries a silver contact and is isolated from the enclosure by means of an isolating washer. The resilient preloading disk ensures excellent performance.
The resilient preloading disk keeps the contact pressure constant throughout the entire temperature range of the BEDIA switch until switching occurs. The mechanically and electrically unloaded bimetal disk snaps over at a preset temperature, with either opening or closing the contact arrangement. The bimetal will only snap back to its initial condition after the temperature has dropped significantly. Compared to other temperature controllers with relatively low hysteresis, the temperature difference between the temperature switch opening and closing is significantly higher so as to a ensure a more obvious status indication, i. e. longer switch-off times, in the event of a fault condition.
Electronical temperature switches
The electronic temperature switch of BEDIA is fitted with thin-film resistor Pt 1000 in a bridge circuit. This sensor element provides close switch point tolerances and quick response. Switch point and reset hysteresis may be selected within the admissible operating range when ordering so as to allow the monitoring of both very wide and very close temperature ranges. The switching output is protected from short-circuiting and overload.
The short-circuit current is limited by the output transistor switching off in the event of a fault. It will automatically reset as soon as the fault has been remedied.
The switch is available with ground-connected, plus-connected, or potential-free DC switching output.
The switch is open in the event of power failure or disconnection of the power supply, independent of the switching function. It is available both as normally open (NO) or normally closed (NC) switch.
Electronical Temperature Sensors
This temperature sensor is for measuring the temperature of liquid and gaseous media in engines, sets of machines, and utility vehicles.
A Pt 1000 thin-film precision resistor is used as the measuring element. The temperature-dependent resistance of the Pt 1000 is evaluated by an electronic circuit and outputted as a temperature-dependent voltage at the sensor‘s output. The interrelationship between temperature and voltage corresponds to the characteristic curve for the Pt 1000 and is thus nearly linear.
The assignment between temperature and output voltage is nearly freely selectable, the lesser temperature corresponding to the lesser output voltage. The sensor‘s lowest possible output voltage is 0.1 V and its greatest is 10 V. The output is overload-proof and short-circuit-proof.
The sensor has no mechanical moving parts and so is not susceptible to vibration and soiling.
Temperature is one of the most measured physical parameters. Despite this, precise temperature measurement is one of the most difficult tasks in motor technology. To meet the constantly increasing requirements for improved motor performance, higher efficiency, and reduced emissions, it is necessary to use reliable and precise sensors in modern motor control systems. The temperature has a decisive influence on process efficiency, energy consumption, and other parameters. Even the service life of machines, equipment, and motors is affected by temperature conditions. In many industry sectors, the most important factor is to use the information from reliable temperature measurements for control and regulation functions.
The increased requirements over the last few years regarding measurement accuracy and reliability of temperature measurements has meant that many equipment operators must reconsider the suitability and performance capacity of their temperature measurement equipment. Resistant thermometers can be used between -200 °C and +850 °C. BEDIA resistance thermometers are known to be the most precise and stable temperature sensors in their measurement properties. An important common property is that their output parameters are available in the form of electric signals that can be relatively easily transferred to measurement and control instruments for processing, storage and display. BEDIA resistance thermometers enable temperature measurements under critical application conditions.
Optimal thermal coupling of the temperature sensor to the housing ensures a rapid response behavior and high measurement accuracy despite its small installation length.