MicroPirani™ and Piezo loadlock vacuum transducers (1000 to 10-5 Torr) with multiple communication options
Designed specifically for loadlock environments, the 901 Plus (901P) Loadlock Transducer (LLT) combines Piezo and Micro Pirani vacuum sensor technology. The combined output provides significantly higher accuracy, stability, repeatability and a faster response time than conventional thermal conductivity gauges.

Key features

  • Absolute pressure measurement from 1,000 to 10-5 Torr
  • 3-sensor functionality in a single transducer for a wide measurement range
  • Analog, RS232, RS485, & EtherCAT® versions
  • Optional integrated touch-screen display available for local pressure indication
  • Fast, accurate and repeatable pressure measurements reduces process cycle time
  • Three optional set points with fast response time for reliable process control

Absolute and Differential Pressure Measurement

The 901P combines both absolute and differential pressure measurement technologies to provide superior performance and functionality. The 901P provides patented, gas independent absolute pressure measurement from 50 -1000 Torr with increased accuracy over thermal conductivity sensors.

MicroPirani™ Sensor Technology

Unlike traditional Pirani gauges, the sensor element in the MicroPirani™ is made of a one millimeter square silicon chip, allowing the measurements to be made in a very small volume. As a result of the MicroPirani™ technology, the 901P can read pressures down to 10-5 Torr, two decades below a standard Pirani sensor. The sensor design minimizes the effects of convection, subsequently the 901P can be mounted in any orientation without compromising accuracy.

Piezo Differential Sensor Technology

The Piezo is a differential pressure sensor, ensuring correct atmospheric pressure measurement under varying barometric pressure conditions. Piezo technology is a direct pressure reading, allowing the measurement to be gas independent. The Piezo sensor measures from -760 to +760 Torr relative to atmospheric pressure.

Analog Pressure Output

The 901P also has an analog pressure output of 1VDC per decade that can be interfaced to external analog equipment for pressure readout or control. Other analog outputs and curves can be selected via the digital user interface. A secondary optional analog output is used to provide the differential pressure measurement.

Three Process Control Relays

The 901P has up to three mechanical relays which can be used for process control, for example interlocking isolation valves and vacuum pumps. Each set point can be assigned either to the differential piezo measurement or the combined absolute MicroPirani™ – Piezo measurement.

Compact Design

The compact design of these vacuum transducers significantly reduces the amount of space occupied by a vacuum gauge. This is particularly appealing to system designers and allows for a more compact vacuum system.

Optional Integrated Touch-screen Display

The optional integrated touch-screen display is user configurable; the user can change pressure units, orientation and has access to set point parameters as well as gas type. The display also indicates the status of the available set point relays. Displayed pressure reading from individual sensors or combined reading can be seen from >5 meters away on the high contrast display.

PDR900 Power Supply & Display

The PDR900 power supply and readout unit is a stand alone, single channel controller for use with the Series 900 digital vacuum transducers. It can be used as a stand-alone power supply readout unit or as a tool for configuration, calibration and diagnostics of system integrated transducers in OEM applications.

KRISTIAN FLODSTRÖM Product specialist Vacuum technology 010-155 03 11