Wire & Cable Markings: Understanding Terminology & Standards

Wire and Cable Markings
UNDERSTANDING THE TERMINOLOGY
PR ESEN TED BY K EN N ETH R I ED L , I N TERTEK
OC TOB ER 2 0 1 7
Copyright © 2017
Intertek Testing
Services NA
Wire and Cable Construction: The Basics
• Conductor – Allows for flow of current
• Insulation – High resistivity/Low conductivity
• Jacket – provides protection for cable core
Wire
Cable
1X8AWG CABLE
CROSS-SECTION
Conductor
Insulation
Jacket
4X14AWG CABLE
CROSS-SECTION
Conductors
Insulation
Jacket
Conductors
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•
•
•
•
•
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Many types
Copper
Aluminum
Copper-Clad Aluminum or Copper-Clad Steel (mainly coaxial cable)
Solid
Stranded: ASTM B8 (Classes AA, A, B, C, D), Others
Uncoated, or Coated to protect, improve conductivity – Tin, Lead, Nickel,
Silver
• Cross-Sectional Area in AWG or mm2 (or kcmil or MCM for large
conductors)
Insulation
• Prevents loss of current and directs its flow – critical for safety
• Usually Polymeric or rubber/polymer blend
• Many types – Thermoplastics and Thermosets - EP (Ethylene
Propylene), PE (Polyethylene), PVC (Polyvinyl Chloride), PTFE
(Polytetrafluoroethylene), etc.
• Tables in UL1581 (Reference Standard) provide summary of types
and physical property (tensile and elongation) requirements
• Will break down and conduct at some voltage level – thus voltage
ratings for cables (Dielectric Voltage Withstand Testing)
Jacket
• Provides protection for the components found within the cable
during installation and use
• Can provide mechanical, chemical, weather (UV) and in some cases
flame resistance
• Usually polymeric or rubber/polymer blend
• Many types – as with insulation
Other Components
• Armor – for additional mechanical protection
• Shield - to prevent external noise from disrupting the cable signals
and to prevent energy in the cable core from causing external
interference
• Braid - on power cables to reduce hazard from insulation leakage,
ensure voltage stresses are held within the insulation
• Fillers – to round out shape of cable
• Rip Cords – To assist with jacket removal
• Strength members – to add tensile strength to overall cable
FIBER OPTIC CABLE
Rip Cord
Optical Fiber
“Loose” Buffer Tube
Central Strength Member
Inner Jacket
Outer Jacket
Why Do We Need Cable Markings?
• Many different cable types and uses
• Variations in materials and constructions to optimize wire or cable
for use in specific installations
• Markings allow the designer, installer, and inspector (AHJ) to
determine at a glance the relevant characteristics of a cable and
confirm that it’s appropriate for the installation
What Determines the Marking Information?
• The Standard!
• WC standards are written for specific uses/applications
• The standard the wire or cable was evaluated to has specific
requirements for markings
• These are based on the constructional and test requirements in the
standard
• These markings need to be placed on the actual wire or cable
and/or the spool or reel or package
What Parameters Do the Markings Tell Us About?
Very Important:
• Voltage Rating
• Insulation Temperature Rating
• Manufacturer
• Conductor Gauge Size
• Flammability Rating
• Evaluation by a Third-Party Lab (ETL, UL, CSA)
What Parameters Do The Markings Tell Us About?
Additional Capabilities:
• Low Temperature Use (usually -40°C)
• Sunlight Resistance, Wet Rating, Direct Burial in earth
• Oil and Gasoline Resistance
Other Capabilities:
• Cable Tray, Exposed Run (-ER), Submersible Pump Cable
• For Communications Cable: Data Transmission Performance
(Category Cables, i.e. ‘CAT6’, ‘CAT5E’, etc.)
How Many Markings Are There?
• Many!
• Markings are dependent on the WC Standard used, and there are
many WC Standards
• Difficult to Cover Them All
• We’ll choose those that cover some of the most common markings:
UL758, UL83, UL44, UL62, UL444, UL1651, UL1063
Recognition versus Listing
• A recognized component is intended to be used within an end
product that will have its own evaluation
• The performance capabilities of a recognized component are
generally limited, so the evaluation for recognition is also more
limited
• Conditions of acceptability in the evaluation report constrain how
the recognized component may be used
• Examples: Switches, relays, motors
Listed Products
• A listed product is a complete product or system, that can function
on its own.
• Safety listings are based on full evaluations to safety standards
Recognized versus Listed Wire and Cable
• With regard to safety, almost all wire and cable is listed
• Most notable exception: UL recognizes Appliance Wiring to UL758
• Intertek lists all wire and cable, including AWM: no recognition
• Verified programs also exist for performance verification; mainly for
data and communications cable to verify transmission performance
UL 758: Appliance Wiring Material (AWM)
• Covers both single insulated conductors (wires) and multi-conductor
cable, with or without optical fiber
• From Scope of UL758: AWM covered are only “for use as factory-installed
wiring either within the overall enclosure of appliances and other
equipment (internal wiring) or as external interconnecting cable for
appliances (external wiring) or for further processing as components in
multi-conductor cables.”
• AWM is intended for factory-install in other listed products, not field
wiring
• AWM cannot be installed in buildings or used as NEC-type cabling
• The end-product the AWM is used with is evaluated (listed) separately
UL 758: Appliance Wiring Material
• Many different types/constructions of AWM
• UL has assigned “style numbers” to distinguish the various types of
AWM
• A given style number is generally produced by many manufacturers
• All style numbers divided into sections from 1 through 5
UL 758: Appliance Wiring Material
Style sections 1 through 5 are defined by:
• Whether the AWM is single conductor wire or multi-conductor
cable
• Whether insulation and jacket compound is thermoplastic or
thermoset
• Thermoplastic – can be repeatedly heated and resoftened
• Thermoset – once cured, cannot be resoftened
UL 758: Appliance Wiring Material
From UL.com:
UL 758: Appliance Wiring Material
• UL has organized all of the AWM styles within its UL.iQ family of
databases
• iq.ul.com
• Select the Appliance Wiring Material Database
UL 758: Appliance Wiring Material
• AWM Database on UL’s Website:
UL 758: Appliance Wiring Material
UL’s AWM database can be searched based on:
• Style attributes (voltage rating, temperature rating, insulation type,
etc.): Returns styles that meet the criteria
• Manufacturers: Returns list of companies that produce that style
• UL E-File Number: Returns list of styles covered under that file
number
• Style Page: Returns page documenting features of that style
• Updates: Returns style sheets that have been updated
UL 758: Appliance Wiring Material
UL 758: Appliance Wiring Material
• Testing and constructional requirements for AWM types are defined
in UL 758 Tables 3.1 to 3.9.
• These are the “roadmaps” for AWM
• Optional tests/ratings are defined in Table 3.9: Flammability, crush,
sunlight resistance, oil and gasoline resistance, wet ratings
• Optional ratings may be important depending on the environment
the AWM is being used in
UL 758: Appliance Wiring Material
• Markings: UL 758 Section 50 (AWM) and Section 51 (Tag, Reel or
Carton)
• Standard does not require marking of the AWM itself
• If the AWM is marked: minimum of ‘AWM’, an identifier for the
manufacturer (either name, symbol or file number) and, if multiple
factories, a marking to identify the manufacturing facility
• Markings for gauge size, number of conductors, etc., are acceptable
if not confusing/misleading
• If an AWM Cable contains a conductive polymeric shield this shall
also be marked on the jacket
UL 758: Appliance Wiring Material
• Tag, Reel or Carton: Many Markings Requirements
• ‘AWM’, intended use of the AWM (internal or external, end-product
name, exposure to gasoline, oil or sunlight), temperature rating,
minimum voltage rating
• Manufacturer name or symbol, distinctive manufacturing location
marking, size and number of conductors (see exceptions in
standard)
• Conductor material, insulation and jacket materials and
thicknesses, month and year of manufacture
• Refer to standard for others
UL 83: Thermoplastic-Insulated Wires and Cables
• Harmonized with CSA C22.2 No. 75, NMX-J-010-ANCE (Mexico)
• Scope covers single-conductor thermoplastic-insulated wire and
cable with 600V rating; certain types have jackets as well
• Thermoplastics can be repeatedly softened by heat, reshaped, and
hardened by cooling
• Standard is written for PVC insulation; other thermoplastics
acceptable if they meet the constructional and test requirements of
the standard
UL 83: Thermoplastic-Insulated Wires and Cables
• General Purpose Wire aka Building Wire
• Covered under NEC Article 310, ‘Conductors for General Wiring’
• Uses defined in the NEC
UL 83: Thermoplastic-Insulated Wires and Cables
• This standard uses ‘Wire Type Designations’ to identify the wire and
define the construction and conditions of use
• These designations follow a specific convention, with letters and
numbers identifying characteristics of the wire or cable
• The designation thus defines some of the attributes of the wire, and
how it can be used
UL 83: Thermoplastic-Insulated Wires and Cables
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T = Thermoplastic Insulation
R = Thermoset Insulation (UL 44)
X = Cross-linked polymeric insulation (UL 44)
H = 75°C Temperature Rating (If no ‘H’ then temp. rating is 60°C)
HH = 90°C Temperature Rating (for dry conditions only)
N = Nylon Jacket
W = Moisture/Water Resistant
U = Underground Use
-2 = Acceptable for use at 90°C in both dry and wet conditions
UL 83: Thermoplastic-Insulated Wires and Cables
• S = Silicone Insulation (UL 44)
• Z = Ethylene Tetrafluoroethylene Insulation
UL 83: Thermoplastic-Insulated Wires and Cables
• Constructional and Test Requirements for the various wire types are
summarized in Table C1 of Annex C
• There are many requirements, though not all apply to every wire
type
• Some tests are long term: Weather Resistance = 30 days,
Long Term Insulation Resistance = 12 weeks (minimum)
Capacitance and Relative Permittivity = 14 days
UL 83: Thermoplastic-Insulated Wires and Cables
• Examples of UL83 Wire Type Designations and their meanings:
TW =
Thermoplastic Insulation, 60°C Dry/Wet Temperature Rating,
Wet Rating
THW = Thermoplastic Insulation, 75°C Dry/Wet Temperature Rating,
Wet Rating
THHN = Thermoplastic Insulation, 90°C Dry Temperature Rating,
no wet rating, Nylon Jacket
THWN-2 = Thermoplastic Insulation, 90°C Dry/Wet Temperature
Rating, Wet Rating, Nylon Jacket
UL 83: Thermoplastic-Insulated Wires and Cables
Required Markings on the Wire/Cable, From Section 6.1:
• Manufacturer’s Name or symbol
• The type designation (if the product complies with the requirements for
more than one type, all types may be shown)
• Conductor Size
• Conductor Stranding Type, if not ASTM Class B or C
• Aluminum conductors marked ‘AL’
• If compact-stranded copper conductors are used, marked ‘Compact
Copper”
• Voltage Rating
UL 83: Thermoplastic-Insulated Wires and Cables
Optional Markings on the Wire/Cable:
• Low Temperature (-40°C, if meets requirements)
• Flame Test Markings (For products that meet the appropriate
requirements, such as FT1, VW-1, FT4, etc.)
• Cable Tray Use (CT, must comply with large-scale, vertical tray flame
test)
• Weather (Sunlight) Resistance = SR, Sunlight Resistant, Sun Res
UL 83: Thermoplastic Insulated Wires and Cables
More Optional Markings on the Wire/Cable:
• Oil Resistance:
60°C Oil Resistance = PRI, OIL RESISTANT I, OIL RES I, OIL RESISTANT
75°C Oil Resistance = PRII, OIL RESISTANT II, OIL RES II
• Gasoline and Oil Resistance (To get gasoline rating, must have oil):
60°C Oil Resistance + Gasoline Resistance = GR I
75°C Oil Resistance + Gasoline Resistance = GR II
UL 83: Thermoplastic-Insulated Wire and Cable
Required Markings on Package:
• Manufacturer’s Name or Symbol
• Type Designation
• Conductor Size
• ‘AL’ if aluminum conductors
• ‘Compact’ if compact conductor stranding used, ‘Compact Copper’
if conductors are compact copper
• Voltage Rating
UL 44: Thermoset-Insulated Wires and Cables
• Harmonized with CSA C22.2 No. 38, NMX-J-451-ANCE (Mexico)
• General Purpose Wire aka Building Wire – NEC Article 310
• Covers single-conductor and multiple-conductor thermosetinsulated wires and cables, with voltage ratings of 600V, 1000V,
2000V, and 5000V
• Thermoset compounds, once hardened, cannot be softened and
reformed (Hardening can be performed by cross-linking, denoted
XL)
• Acceptable thermoset insulation materials covered by Clause
4.2.1.2 and Table 19, and include XLPE, EP, Silicone, CPE, others
UL 44: Thermoset – Insulated Wires and Cables
• Like UL83, this standard also uses ‘Wire Type Designations’ to identify
the wire and define the construction and conditions of use
• Some UL 44-Specific Designations:
R = Thermoset Insulation
X = Cross-linked Insulation
S = Silicone Insulation (Thermoset)
75 or 90 after W indicates temp rating for both dry and wet
UL 44: Thermoset-Insulated Wires and Cables
• Examples
RHH = Thermoset Insulation, 90°C dry temperature rating, no wet
rating (600V and 2kV only)
R 90 = Thermoset Insulation, 90°C dry temperature rating, no wet
rating (600V, 1kV, 2kV, 5kV)
XHHW-2 = Cross-Linked Thermoset Insulation, 90°C Dry/Wet
Temperature Rating, Wet Rating
RWU 75 = Thermoset Insulation, wet rating, underground use,
75°C Dry/Wet
UL 44: Thermoset-Insulated Wires and Cables
• Exceptions: Sometimes, the identifying letters and numbers don’t
seem to fit
SIS = ‘Stranded Insulated Switchboard’ Wire. Not silicone insulation,
as the ‘S’ might indicate, but actually cross-linked polyethylene
• Sometimes wires are dual-listed, after being tested to the more
stringent set of requirements
Example: SIS sometimes carries XHHW designation as well.
UL 44: Thermoset-Insulated Wires and Cables
• The various wire types covered are shown in Table One
• Many tables in standard to define constructional parameters:
conductor diameters and resistances, insulation and jacket
thicknesses and tensile properties, IR values, etc.
• Annex B is a summary of constructional and test requirements for
all wire types covered in the standard
• Marking requirements similar to those of UL83
• Optional ‘CT’ marking for Cable Tray use: if wire meets vertical tray
flame test or FT4 flame test and is single circuit conductor ≥ 1/0 or
equipment grounding conductor ≥ 4AWG
UL 62: Flexible Cords and Cables
• Harmonized with CSA C22.2 No. 49, NMX-J-436-ANCE (Mexico)
• Not all cord types shown are approved in US, Canada and Mexico
• National differences indicated by superscript above cord type:
c = Canada only
m = Mexico only
u = United States only
Also c,m and c,u and m,u
UL 62: Flexible Cords and Cables
• Covers cords and cables rated 600V maximum
• Most commonly known for service cords (thermoplastic and
thermoset insulation) for the connection of portable (movable)
appliances, machines, tools
• This standard also covers elevator and hoistway cables, heater
cords, range and dryer cords, decorative lighting cords, tinsel and
lamp cords, electric vehicle cable and special-use cords
• For US, These cord types are covered under NEC Article 400 –
Flexible Cords and Flexible Cables
UL 62: Flexible Cords and Cables
• This standard also uses type designations to identify flexible cords
and cables and define their constructions and conditions of use
• These designations use letters and numbers to identify the
characteristics of the cord or cable
• The designation thus defines some of the attributes of the cord,
and how it can be used
• Some exceptions, where designations may not fit the letter/number
type convention
UL 62: Flexible Cords and Cables
• H = Heater Cord
• E = After first letter indicates thermoplastic elastomer insulation
and jacket
• NI = Non-integral; indicates separate insulation and jacket
components in parallel cords
• O = oil resistant (jacket only), OO = oil resistant (insulation and
jacket)
• P = Parallel conductor cord (conductors not twisted)
UL 62: Flexible Cords and Cables
• S = Extra-Hard Usage Flexible Cord (rated 600V), when not followed by J,
V, or P
• SJ = Hard Usage Flexible Cord (rated 300V)
• SV = Not-Hard Usage Flexible Cord (rated 300V, aka ‘vacuum cleaner
cord’
• T = After first letter indicates thermoplastic insulation and jacket
• -1, -2, -3 = for parallel cords, indicates relative insulation thickness,
thinnest to thickest
• W = Wet-rated and sunlight resistant
• -R = After cord designation, indicates rough service for power supply
cords
UL 62: Flexible Cords and Cables
• Examples:
NISPT-1 = Non-integral (separate) insulation and jacket, parallel cord,
thermoplastic insulation and jacket, thinnest insulation for parallel
cord type
HSJO = Heater cord, hard usage, oil resistant jacket
SOOW = Extra-hard usage, oil-resistant insulation and jacket, wetrated and sunlight resistant
SVT = Not-hard-usage, thermoplastic
DRT = Canada-only, dryer and range cord, thermoplastic
UL 62: Flexible Cords and Cables
• Tables and Figures in UL62 are very important – they help define
the constructions and the test requirements
• Examples:
Table 8 = Insulation Materials
Table 15 = Thermoset Service Cords
Table 20 = Thermoplastic Service Cords
Figure 1 = Dimensions of two and three conductor parallel cords
UL 62: Flexible Cords and Cables
• Markings covered in Section 6
• All cords require on product: Manufacturer ID, type designation, max
temperature rating, number of conductors and sizes, voltage rating
• Additional Markings: low temp, shielded, “-R”, flame test
• Optional Markings (Section 6.3): Compound designations, part number,
etc.
• Package marking covered in Section 6.4
• Hoistway, RV, mobile home cords: Refer to Section 6 for specific marking
requirements
UL 444: Communications Cables
• Harmonized with CSA C22.2 No. 214
• Covers single or multiple conductor cables for communication
circuits, including coaxial cable (single conductor with dielectric and
shield)
• May contain optical fiber
• Rated 300V maximum (not marked), 60°C to 250°C
• Covered by Article 800 of the National Electrical Code
UL 444: Communications Cables
• Flame Test Classification: Very Important Required Marking
Highest to Lowest, these are based on the flame test performed:
CMP = plenum, complies with NFPA 262 (Steiner Tunnel), suitable for
use in environmental air-handling spaces
CMR = riser, complies with UL1666, suitable for running in shafts
between building floors
CMG = General Purpose, complies with UL1685 Vertical Tray (FT4/IEEE
1202) (i.e. method 2 in UL1685)
UL 444: Communications Cables
• CM = General Purpose, cross-connect; complies with UL1685
vertical tray (UL Flame Exposure, i.e. Method 1 in UL 1685)
• CMX and CMUC (under carpet) = complies with VW-1 small-scale
test
• CMH = complies with small-scale vertical flame test/FT1 in UL/CSA
2556
• Flame test criteria include flame spread distance, smoke
release/density, cable damage (large scale) or continued burning of
wire, flaming of cotton, damage to indicator flag (small scale)
UL 444: Communications Cables
Other Required Markings:
• Conductor Size, quantity of each size if sizes mixed
• Manufacturer Identification
• Temperature Rating for cables rated over 60°C
• ‘CMX Outdoor’ if meets 300 hour weatherometer (UV) and cold impact
test
• ‘Audio Only’ for cable (not coax) that uses 15 – 6 AWG copper conductors
• ‘Sunlight Resistant’ or ‘sun res’ if cable meets 720 hour sunlight
resistance test
UL 444: Communications Cables
Optional Markings:
• ‘Shielded’ if cable contains shields
• Temperature rating for 60°C rated cable
• ‘CI’ for cables that comply with circuit integrity flame test per
UL2196 (maintain operation under burning conditions for two
hours; used for emergency communication and alarm systems)
• ‘-LP (XX)’ for cables that comply with heating test in Clause 7.24 of
UL444 - conduct rated current while bundled in conduit without
exceeding insulation temperature rating (XX = 0.5A to 1.0A)
UL 1063: Machine-Tool Wires and Cables
• US-Only Standard
• Covers Type MTW wires and cables for use with machinery as defined in
NFPA 79 (Industrial Machinery, Chapter 12) and NFPA 70 (NEC, Articles
310 and 670)
• Usage includes machine tools, industrial machines for plastics, wood,
material handling, assembly, packaging, test/inspection
• Type MTW wires rated 600V, 90°C dry, 60°C wet
• Moisture and oil resistant; comply with flame test
• Thermoplastic insulated conductors (PVC) without jacket (Construction
A) or with nylon jacket (Construction B)
UL 1063: Machine Tool Wires and Cables
• Overall PVC jacket used with multiconductor cables
• Flame test is small-scale vertical flame per UL1581 Section 1060 or
UL1581 Section 1080 (VW-1) + UL 1581 Section 1100 (small-scale
Horizontal Specimen FT2)
• Markings on Wire: Manufacturer; factory id (if produced at more
than one factory); ‘MTW’; ‘600V’; Gauge size if conductor size does
not correspond to AWG or kcmil sizes in UL1063 Table 6.2; ‘flexing’,
‘Class K’, ‘constant flexing’, or ‘Class M’ depending on gauge size, if
conductors are appropriate for flexing service per Table 6.6,
stripes/colors per Section 29 to identify equipment-grounding
conductors, grounded and ungrounded circuit conductors
UL 1651: Optical Fiber Cable
• US-Only Standard (CSA equivalent is C22.2 No. 232)
• Covers single and multiple fiber cables for communications,
signaling, and control
• Does not cover cables containing current-carrying conductors
• Covers safety only, not optical performance
• Uses defined under Article 770 in the NEC
UL 1651: Optical Fiber Cable
Cable types are based on flame classifications:
• OFNP, OFCP = plenum (nonconductive, conductive) (NFPA 262)
• OFNR, OFCR = riser (nonconductive, conductive) (UL 1666)
• OFN, OFC = general purpose (nonconductive, conductive) (UL1685:
UL Test or FT4/IEEE 1202, smoke measurements NA)
• OFNG, OFCG = general-purpose (nonconductive, conductive) (UL
1685: FT4/IEEE 1202, smoke measurements NA)
UL 1651: Optical Fiber Cable
Markings on Cable:
• Type Designation
• Manufacturer
• ‘Limited Combustible’ for OFNP or OFCP if cable complies with NFPA 90A
(Installation of Air-Conditioning and Ventilating Systems)
• ‘-LS’ optional (limited smoke), for cables that comply with smoke
requirements in UL1685
• ‘sun res’ or ‘sunlight resistant’ for cable that complies with 720 hours of
UV testing
• Temperature Rating for cables rated over 60°C
Summary
• Many different wire and cable markings, because there are many
different wire and cable constructions and uses, and many different
wire and cable standards
• Markings are dependent on the standard used to evaluate the wire
or cable
• The standards and the relevant electrical codes (NEC, CEC) are the
best sources of information for interpreting the markings
Thank You For Attending!