LPGmass
Hauser
3
Document information
Symbols used
Electrical symbols
Symbol
Meaning
Direct current
Alternating current
Direct current and alternating current
Ground connection
A grounded terminal which, as far as the operator is concerned, is grounded via a
grounding system.
Protective ground connection
A terminal which must be connected to ground prior to establishing any other
connections.
Equipotential connection
A connection that has to be connected to the plant grounding system: This may be a
potential equalization line or a star grounding system depending on national or
company codes of practice.
Symbols for certain types of information
Symbol
Meaning
Permitted
Procedures, processes or actions that are permitted.
Preferred
Procedures, processes or actions that are preferred.
Forbidden
Procedures, processes or actions that are forbidden.
Tip
Indicates additional information.
Reference to documentation
A
Reference to page
Reference to graphic
Visual inspection
Symbols in graphics
Symbol
Meaning
1, 2, 3,...
Item numbers
1.
,
2.
,
3.
…
Series of steps
A, B, C, ...
Views
A-A, B-B, C-C, ...
Sections
-
Hazardous area
.
Safe area (non-hazardous area)
Flow direction