Northern Connectors Souriau MBG Plastic Circular Connectors - Manual (Page 21)

21
MBG Series
Glossary of terms
• Clearance
Per the IEC 60664-1 it is the shortest
distance between two conductive parts
even over the air.
• Creepage distance
Per the IEC 60664-1 it represents the
shortest distance along the surface
of the insulating material between two
conductive parts.
• Working voltage
Per the IEC 60664-1 it is the highest r.m.s. value of A.C. or D.C.
voltage across any particular insulation which can occur when the
equipment is supplied at rated voltage.
• Rated impulse voltage
Impulse withstands voltage value assigned by the manufacturer to
the equipment or to a part of it characterizing the specifi ed withs-
tand capability of its insulation against transient overvoltage.
• Working current
It is the maximum continuous and not interrupted current able
to be carried by all contacts without exceeding the maximum
temperature of the insulating material.
• Transient voltage
Extract from the IEC 60664-1: Short duration overvoltage of
a few millisecond or less, oscillatory or non-oscillatory, usually
highly damped.
• CTI (Comparative Tracking Index)
The CTI value is commonly used to characterize the electrical
breakdown properties of an insulating material. It allows users
to know the tendency to create creepage paths. This value
represents the maximum voltage after 50 drops of ammonium
chloride solution without any breakdown.
• RTI (Relative temperature Index):
Extract from ULs website:
“Maximum service temperature for a material, where a class of
critical property will not be unacceptably compromised through
chemical thermal degradation, over the reasonable life of an
electrical product, relative to a reference material having a
confi rmed, acceptable corresponding performance defi ned RTI.
- RTI Elec: Electrical RTI, associated with critical electrical
insulating properties.
- RTI Mech Imp: Mechanical Impact RTI, associated with
critical impact resistance, resilience and fl exibility
properties.
- RTI Mech Str: Mechanical Strength (Mechanical
without Impact) RTI, associated with critical
mechanical strength where impact resistance,
resilience and fl exibility are not essential”
Air gap
Creepage distance