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#41232 - 08/19/04 12:16 PM Cable terminology
RickC Offline
Junior Member

Registered: 08/19/04
Posts: 1
Loc: Richmond Hill, ON
What do the R and W stand for in RW90 rated cable

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#41233 - 08/19/04 02:04 PM Re: Cable terminology
cpal Offline

Registered: 05/17/04
Posts: 165
Loc: Cohasset MA
the following is a part of the insulation information available from the UL Marking Guide for Wire and Cable. You can download the entire publication at
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It is resonablly comprehensive.

you can get a feel for types of insulations by referring to Articles 310.12 Marking, and Table 310.13 Conductor Application and Insulations .

In general R = Thermoset (type of insulation), and W indicates suitable for wet locations

Hope this helps

charlie P

NEC® Article 310, Table 310-13
A — Asbestos (obsolete; now must be glass fiber or similar material)
FEP — Fluorinated ethylene propylene insulation
H — 75oC (Note: Lack of “H” indicated 60oC)
HH — 90oC
L — Lead sheath
N — Nylon jacket
PF — Perfluoroalkoxy insulation
R — Thermoset insulation
S — Silicone (Thermoset) insulation
T — Thermoplastic insulation
U — Underground use
W — Moisture resistant
X — Cross-linked synthetic polymer insulation
Z — Modified tetrafluoroethylene insulation
Examples: RHW

[This message has been edited by cpal (edited 08-19-2004).]


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