ISO 14617-2-2002 pdf free download.Graphical symbols for diagrams – Part 2: Symbols having general application.
3.17
characteristic quantity
measuring device) quantity whose name characterizes the device and its function
EXAMPLE The characteristic quantity for a safety valve is “pressure”; for an overcurrent relay, current”.
[IEC 60050-4461
3.18
pilot switch
monitoring device actuated In response to specified conditions of a non-electric characteristic quantity
EXAMPLE Pressure, temperature, speed, flow rate o liquid level.
[IEC 60050441)
3.19
logic negation
condition mainly used with binary logic elements where the logic state 1 (TRUE) is converted to a logic state 0 (FALSE) or vice versa
[IEC 60617-12. IEC 61082-2)
3.20
logic inversion
condition mainly used with binary logic elements where a higher physical level Is converted to a lower physical level or vice versa
[IEC 6061 7-12, IEC 61082-2)
3.21
feedback controller
device in which the control action is made to depend on the measurement of the controlled variable
[IEC 60050-351)
3.22
variability
ability of changing a property
cf. adjustability (3.23) and inherent variability (3.25)
3.23
adjustability
ability to adjust the setting of a component or device
[IEC 60050-371J
cf, variability (3.22)
3.24
pre-set adjustability
ability to adjust the setting of a component or device before normal service.ISO 14617-2 pdf download.