5
Hauser
Prosonic T - FMU 130, 131, 230, 231, 232
Safety Conventions and Symbols
In order to highlight safety-relevant or alternative operating procedures in the manual,
the following conventions have been used, each indicated by a corresponding icon in
the margin.
Explosion Protection
Symbol
Meaning
Device certified for use in explosion hazardous area
If the Prosonic T has this symbol embossed on its nameplate, it can be
installed in an explosion hazardous area.
Explosion hazardous area
Symbol used in drawings to indicate explosion hazardous areas. Devices
located in and wiring entering areas with the designation “explosion
hazardous areas” must conform with the stated type of protection.
Safe area (non-explosion hazardous area)
Symbol used in drawings to indicate, if necessary, non-explosion
hazardous areas. Devices located in safe areas still require a certificate
if their outputs run into explosion hazardous areas.
Electrical Symbols
Symbol
Meaning
Direct voltage
A terminal to which or from which a direct current or voltage may be
applied or supplied.
Alternating voltage
A terminal to which or from which an alternating (sine-wave) current or
voltage may be applied or supplied.
Grounded terminal
A grounded terminal, which as far as the operator is concerned, is
already grounded by means of an earth grounding system.
Protective grounding (earth) terminal
A terminal which must be connected to earth ground prior to making any
other connection to the equipment.
Equipotential connection (earth bonding)
A connection made to the plant grounding system which may be of type
e.g.neutral star or equipotential line according to national or company
practice.
