Functional safety and maximum availability can go together
Passive isolators with a technologi-cal advantage: fewer parts mean rare failures. For measurement and safety reasons, analog signals are routinely isolated in industrial facilities.
The requirements on plant and safety-related circuits are continuously increasing, for instance because of a growing awareness of occupational safety. Thereby, the technical require-ments on components are also being raised. However, higher functional safety is often bought by more effort and at the expense of availability. This does not have to be the case, as proven by the new ProLine P 22400 passive isolator for standard signals.
Its operating principle enables the implementation of a product that combines high functional safety with high availability in a unique way – a balancing act that would otherwise be hard to achieve.
Facts and Features
Functional safety up to SIL 3 acc. to EN 61508 with certificate from an accredited testing body
Average failure rate MTBF: 965 years
Low transmission error 0.08 % full scale
High isolation including protec-tion against electric shock by reinforced insulation up to 600 V AC/DC
Test voltage 5.4 kV AC
Minimal losses and low installation effort thanks to loop-powered operation
Mechanically stable approved by an independent test-ing laboratory, suitable for marine applications
Ambient temperature range during operation: -40 ... +85 °C
Resistant against electromagnetic interferences, meeting stringent SIL requirements
ProLine P 22400’s safety functionality is the highly precise, linear transmis-sion of 4 ... 20 mA signals.
A high level of functional safety can be achieved even in single-channel structure and without diagnostics. For instance, sensors and actuators in safety circuits can be directly connect-ed, requiring no elaborate evaluation equipment for redundant structures. At the same time, the device has a low total failure rate and provides high availability. After all, what good is a safety device that will keep turning off (switch to a safe state) and thereby regularly close down the facility it is meant to monitor?