ING.-BÜRO ANDREAS RÜHMER

The pressure transmitters of the 4LD series use the chip-in-oil technology developed by KELLER, uniting a pressure measuring cell, digital temperature compensation and signal processing in a compact housing made of stainless steel or Hastelloy. The transmitters are extremely resistant to environmental influences and delivery highly accurate measurement results as a digital output signal. The I2C interface and the low supply voltages make it easy to integrate in microcontroller-based systems. The extremely low power consumption is ideal for battery-operated devices. The D line is perfect for IoT solutions.

The pressure transmitters of the 35XHT series are suitable for use in media temperatures up to 150 °C and can therefore be used in bioreactors and autoclaves that have to be sterilised regularly. They use digital compensation with a mathematical model to achieve an accuracy of 0,15 %FS – in the temperature range from 10 to 40 °C, this value even corresponds to the total error band. In addition to the digital RS485 interface, the X-line transmitters have a rangeable, analog current or voltage output. The standard model of the 35XHT series has an Ingold fitting as pressure connection.

The differential pressure transmitters of the PRD-33X series are designed for accurate measurements in low pressure ranges with very high overload on both sides. In addition to the differential pressure sensor, which may only be exposed to gases at its rear face, the devices have an additional absolute pressure sensor that measures the line pressure. Both measured values are output via the digital RS485 interface and are the ideal basis for cryogenic tank monitoring.

The 22DT series has been specially developed for use in bivalent vehicles (volume flow measurement when running on natural gas) and is homologated for the automotive industry. However, it also has other industrial applications. The NTC or PT temperature sensor located directly beneath the steel diaphragm reacts more quickly to temperature changes thanks to its special design. The pressure transmitters are protected against electromagnetic fields up to 200 V/m and output the measured values as a ratiometric 0,5...4,5V analog signal. The connections of the temperature sensor are fed out directly.