The new BERU RIS sensor (Radiator Identification Sensor) is used for detection and function testing of a catalytic coated radiator. In addition, it measures the temperatures on the cooler and passes these on to the engine control unit.

Electronic control systems which pick up a wide variety of different parameter with highly accurate sensors are being used increasingly in motor vehicles. BERU sensors are developed in co-operation with the automotive industry and are adapted exactly to the respective application in the vehicle. The emphasis is on functional safety under extreme operating conditions.

The sensors which are represented here are special developments for the automobile industry and its systems suppliers.

You will find the sensor range for the International Aftermarket (IAM) in the latest Sensor Catalogue or in the BERU Product Finder.

Temperature sensors

Function:

Temperature sensors are used for the exact measurement of ambient temperatures.

Measuring principle:

The sensor measures the temperature with a temperature-dependent resistor, e.g. a hot wire (NTC) or a thin-film platinum measuring resistor. The characteristic is stored in a control unit and therefore allows calculation of the temperature.

Variants:

• Radiator Identification Sensor (RIS)
• High temperature sensor (HTS)
• Miniaturised sensors

Speed sensors

Function:

Sensors for measuring speeds.

Area of application:

Engine control (crankshaft, camshaft), gear (drive and power takeoff speed), ABS systems (wheel speed).

Measuring principles:

Inductive transmitter
A measuring method in which a coil measures changes in the magnetic flow created by a tooth/gap geometry. The rotational movement of the gear wheel induces a voltage in the coil. The necessary magnetic field is supplied by the integrated permanent magnet. The transmitter wheel speed determines the amplitude and frequency of the induced alternating voltage.

Hall transmitter
Electronic measuring principle with the "Hall Effect". The sensitive element of the speed governor is a static or dynamic "Hall-IC" which gets its bias from a permanent magnet (back bias). The "Hall" evaluates the magnetic flow density in the hall plates and assigns them switching states (high/low) with an evaluation circuit. If a gear wheel moves past the sensor, the sensor signal projects the tooth geometry. The signal amplitudes are largely independent of the speed and distance from the gear wheel which gives it a clear advantage over inductive systems. In addition, the high integration of the Hall sensors enables intelligent sensors which have self-calibration functions for example.

Variants:

• Inductive sensors with and without permanent magnet
• Hall sensors with direction of rotation detection
• Hall sensors with 2-wire interface

Distance sensors

Function:

Distance sensors measure distances, positions and angles in modern automobiles with high accuracy.

Areas of application:

Coupling systems, brake systems, gear shifts or actuators.

Measuring principles:

The following measuring principles play a role in the automobile industry: potentiometric, inductive, magnetostatic. The distance sensor developed by BERU is a magnetostatic sensor. It measures distances up to 50 mm with an analogue „Hall Effect“ sensor. This sensor can be set to the respective measuring tasks by programming.

Variants:

• Sensors with PWM interface
• Sensors with analogue output
• Sensors with linearisation (support points)
• Sensors with redundant signal

Media sensors

Function:

Media sensors can detect and distinguish between different media. The water sensor, for example, monitors the water level in fuel filters and therefore protects against corrosion. Bio diesel sensors measure the mixing ration of bio diesel and mineral diesel, and together with the engine control unit, enable compliance with the emission limit values even in bio diesel operation.

Areas of application:

Water detection in fuel filters, fuel differentiation.

Measuring principles:

The water/diesel sensor measures the conductivity of the medium between two electrodes and sends the switching signal (open collector) when the water level reaches the electrodes. The bio diesel sensor uses the different dielectric constants of diesel and bio diesel, measures these as a change in capacitance in the measuring capacitor and transforms them into an analogue voltage signal.

Variants:

• Water sensor
• Bio diesel sensor

Other BERU products with sensor applications can be found on the pages:

• Pressure Sensor Glow Plug (PSG)
• Lambda probes
• Tyre pressure control systems