November 2013
Know Your Symbols

Know Your Symbols

07 November 2013

Much like the highway system, the electrical industry has adopted standard symbols that provide instant recognition of concepts and warnings, in place of pedantic written descriptions. These symbols appear on electrical test equipment, often as pop-ups in the display. For operators who have not been provided with requisite familiarity, they can be mistaken for alarms. Generally, they are advisories to direct the operator’s attention and guide proper usage. By no means a complete glossary, but some of the common symbols are as follows:   CautionCaution: doesn’t mean that anything is necessarily “wrong”, but directs the operator’s attention to some relevant condition. For instance, an indicator of some problem with the test setup may have lit, but can be overlooked in studying the measurement readings. The caution symbol reminds the operator to change focus and look around.   ShockRisk of shock: doesn’t mean that the operator is in imminent danger, but is a reminder that a voltage is present and industry standard safe working practice is in order, relevant to the type of test being performed and instrumentation used.   Double Insulation Double insulated: indicates Class II electrical products, where the operator is protected by double insulation in lieu of a grounding conductor in the line cord.   Line PowerLine power: may seem like a no-brainer, but it’s not. For convenience, many electrical testers have dual operation, from either battery or line (plug in) power. There is a considerable difference in safety requirements between the two, and it’s helpful that the operator be kept aware of the possibilities.   CE CE Mark: equipment complies with current EU directives regarding its ability to both emit and receive “noise” interference to and from adjacent electrical equipment.   C tick   C-tick: don’t worry about this one, unless you’re in an Australia market!     Do Not Dispose   Do not dispose of in normal waste stream: this is for the environment; product contains chemicals or materials that should not enter ground water or landfill, but should be disposed of discreetly.   Ground   Indicates a ground connection.     USB Universal serial port (USB).   CAT Rating“CAT Rating”: this is an important IEC directive that indicates equipment’s level of safety from arc flash/blast, and where it can and cannot be used. Be familiar with this one!