Contents
How is the safety of an intrinsically safe circuit affected?
Where intrinsically safe apparatus is interconnected by wiring, the safety of each piece of apparatus is affected by the performance of the other pieces of apparatus in the circuit. The safety technique relies on the system being correctly designed and intrinsic safety becomes a system concept.
What are the requirements for an intrinsic safe system?
The essential requirements of an intrinsically safe system are: • The system must work. • The apparatus in the system must be ‘certified’ or ‘simple’. • The compatibility of the apparatus must be established. • The level of protection of the system established.
Why is intrinsic safety important in instrumentation cables?
j) Intrinsic safety permits the use of conventional instrumentation cables, thus reducing costs. Cable capacitance and inductance is often perceived as a problem but, in fact, it is only a problem on cables longer than 400 metres, in systems installed in Zones 0 and 1, where IIC gases (hydrogen) are the source of risk.
How are intrinsic safety techniques used in the real world?
Intrinsic safety technique required the use of equipment and wiring which is incapable of releasing sufficient electrical or thermal energy under normal or abnormal conditions.
What are the safety components of an exveritas circuit?
Use of safety components (zener shunt, diodes for blocking and inductance control, resistors with capacitance) and safety component rating and de-rating (zeners). All delegates on our intrinsic safety training course will receive a free licence for ExVeritas unique on line intrinsic safety assessment tool.
Why are inductors and capacitors important to safety?
Consequently, the standard provides curves and tables to help to determine with a safety factor, the maximum acceptable voltages and currents, in particular when capacitors and inductors are implemented because they store energy.