Using Keller’s LEX 1 Instrument for Advanced Digital Pressure Measurements

Keller UK's new, advanced digital pressure measuring instrument is precise, flexible and integrated with Max.-/Min.-function for testing and calibration purposes. The LEX 1 instrument is controlled by a microprocessor and includes two operating keys. Users can utilize the left key to switch on the instrument and choose the pressure units and functions, while the right key can be selected to display the minimum and maximum values and to perform the selected function of the respective unit. The pressure is determined two times per second and then gets displayed. The display on the top denotes the exact pressure, while the display on the bottom shows the minimum and maximum pressure since the last RESET.LEX 1 Ei is also provided as an intrinsically safe version.

The measured pressure can be displayed on a personal computer or laptop using the KELLER converter cable and the READ30 software. The READ30 software enables users to record the graphic display and pressure signals on the computer. Approximately 128 instruments can be attached to a Bus-system.

Dead weight testers are important criteria for pressure, wherein the pressure is calculated by the primary values of time, length and mass. On the other hand, primary criteria in national laboratories demonstrate a vagueness of their pressure references with 70 to 90 ppM or near to 0,01%.

Keller employs commercial dead weight testers to calibrate the transmitters. Manometers demonstrate a precision or uncertainty of 0,025 %. KELLER uses the term "precision" for values less than these levels which is the capability of a manometer or pressure transmitter to be at each pressure point within 0.01 % FS in terms of these commercial criteria. Full-scale output of the manometer can be configured to complement any standard of choice by rectifying the gain through a calibration software.

Specifications

The specifications of the LEX 1 digital manometer are provided in the table below: