New SIL Pressure Transducer

IEC 61508 defines the requirements concerning safety-related systems in systems. This standard for functional safety describes Safety Instrumented Systems (SIS) and categorises them into Safety Integrity Levels (SIL 1 to SIL 4).

Afriso (Germany) has evaluated all series DMU piezo-resistive pressure transducers relevant for the process industry according to IEC 61508 (basic) and IEC 61511 (process industry). Two different measuring principles are used to monitor relative and absolute pressure. The robust, ceramic thick-film sensors of series DMU 01 allow for pressure measurement of almost all gases and liquids that are not aggressive to the FKM seal used in the pressure channel. This aluminium oxide sensor is also available in a flush mounting version for abrasive media such as bulk solids. The oil-immersed silicon measuring cells of series DMU 03 and DMU 04 are adapted without seals to the front-mounting process connections. The DMU 08 transducer with the same measuring principle is used for hydrostatic level measurement. All DMU pressure transducers were rated SIL 2. The safety-related characteristics are provided via the manufacturer’s declaration. As a result of the evaluation, these two sensor systems can be used in potentially explosive areas with measuring ranges from 40 mbar to 600 bar and vacuum.