At the last Johannesburg branch technology evening Extech Safety Systems sales director, Gary Friend, gave a presentation on intrinsic safety – a preferred protection technique for many instrumentation installations. The presentation started with an overview of the Piper Alpha disaster in the UK to highlight the importance of intrinsic safety. Then, the origins and principles of IS were examined, including hazardous area zoning and the implications for dust. Gary covered the three principles of Exi design, area classifications and levels of protection. He then examined the principles and compared the use of zener barriers versus galvanic isolators and provided insight into how loop approvals are done and cable lengths calculated. The presentation ended with a brief look at IS for Foundation Fieldbus, serial devices and Ethernet.

The presentation was accredited for CPD points. The validation number is SAIMC_CPD_S_035.

Forthcoming events

* August – Ster Kinekor on cinema automation.

* September – Endress+Hauser on energy management.

* October – Gilroy’s.

* November – year-end (TBC).

Queries: Debbie Scott, 0861 776237, wnip@iafrica.com