STW Controllers are SIL2 Certified
Internationally the standard for the "Functional safety of electrical/electronic/programmable electronic safety-related systems" is IEC 61508. This standard contains, among many other points, the assessment of risks (safety integrity levels) and the corresponding control measures.
The term Safety Integrity Level (SIL) is defined as a relative level of risk-reduction provided by a safety function, or to specify a target level of risk reduction.
In the field of mobile equipment, personal protection and safeguarding must be given the highest priority in the planning, developing, operating, and maintaining of mobile equipment. Before equipment is put into service, it should be subjected to a hazard and risk analysis to define the safety requirements. Such a risk assessment can be accomplished thru a risk assessment chart.
The following main risk parameters are used as basic definitions for such an assessment.
C1 Minor injury
C2 Serious permanent injuries to one or more persons, death to one person
C3 Death to several people
C4 Very many people killed
Frequency of and exposure time in hazardous zone (F)
F1 Rare to more often
F2 Frequent to permanent
Possibility of avoiding the hazardous event (P)
P1 Possible under certain conditions
P2 Almost impossible
Probability of the unwanted occurrence (W)
W1 Very slight probability and only a few unwanted occurrences
W2 Slight probability and few unwanted occurrences
W3 Relatively high probability and frequent, unwanted occurrences
An example of a SIL2 requirement could be C2+F2+P2+W1 as shown in the risk graph above.
STW has several controllers in the "ESX" family that offer SIL2 hardware/software solutions. While many applications do not require SIL2 controllers STW is proud to be able to offer a solution to those that do require SIL2. Please inquire with STW if your application requires a SIL2 controller.