DC Cable Specifications And Safety Regulations

DC Cable Specifications And Safety Regulations

The safety requirements for power cords (Flexible Cords and Cables) are clearly stated in the CSA standard C22.2 No. 49-98 edition. In order to enable readers to understand the relevant requirements before R&D and manufacturing, the labeling, structural requirements, and safety tests are hereby provided. The three parts are explained and introduced as follows.

Labeling (Marking)

Marking on the wire ( mandatory requirement ): 610 mm on the electrical wire must appear at least once.

  1. Company name ( or CSA contract number, registered trademark/trade name ).
  2. Temperature grade (higher than the lowest temperature must be printed on the electrical wire ).
  3. Wire type, wire diameter, and number ( such as SPT-2 16AWGX3C) . Note: Non-integral ( Double Insulation ) in the CSA standard cannot be marked with the word NI on the wire. This standard is only regarded as a structural difference.
  4. Combustion level (FT1, FT2, or FT4, if the wire meets FT4 or VW-1, it is not necessary to mark FT1 or FT2, if it meets FT1, it may not be marked FT2).

Mark on the electric wire ( printing is required for the following cases )

VW-1SC means that the core wire of the wire must pass the vertical combustion test

VW-1 is a single wire (finished product) that has passed the vertical combustion test

Now UL has requested the cancellation of VW-1SC printing in 2005!

  1. For outdoor cables such as SJOOW, SOW…, the temperature class is marked with -40 ℃.
  2. SHIELDED should be printed on those with jacket cover.
  3. If the conductor is a steel wire, it should be printed with STEEL CORE.
  4. If the material is TPE (Thermoplastic Elastomer ), TPE insulation and jacket should be printed.
  5. SPT-1, SPT-2, SPT-3, and HPN have ground wires, Green conductor for Grounding Only or Green conductor with yellow stripes for Grounding Only.

Mark on the wire ( not mandatory ): When the customer has the following requirements, it can be printed.

  1. Voltage value.
  2. W type can be printed water-resistant or water-resistant 60C.

Mark on the package ( mandatory requirement ) :

  1. Company name ( or CSA contract number, registered trademark/trade name ).
  2. Date of electrical cable manufacture ( labeled at least year and month ), or other distinguishable codes.
  3. Wire type, wire diameter, and number ( such as SPT-2 16AWGX3C).
  4. Voltage value.
  5. SPT-2 uses 30AWG conductors and should be marked FOR USE IN GENERAL USE EXTENSION CORD SETS ONLY.
  6. When PXT and SPT-1 are 20AWG, it should be marked as NOT FOR RETAIL SALE TO THE PUBLIC.
  7. The product has special conditions: such as Small or large diameter cord in process or Not for general use.

Wire use range

  1. Extra-hard-usage cord : ( Such as ST series ) “Used on large power and movable equipment, with the highest level of mechanical strength.
  2. Hard-usage cord : ( Such as SJ, SPT-3, etc. series ) “Used on relatively medium power and hand-held equipment, with medium mechanical strength.
  3. Not-for hard-usage cord : ( Such as SVT, SPT-1, SPT-2, etc. series ) “Used on lighting products, it is not easy to bend during use, and it must not be a hand-held product during use. Inferior mechanical strength.
  4. Special Use Power Cords : ( such as PXWT, CXWT, PXT, TX) “Special power cords are generally used for indoor/outdoor Christmas light strings and other products.

5.Tinsel cord: Copper foil wire is used on products that are often twisted, such as charging wires for electric razors.

Wire structure (Construction)

1.Conductor:

Must use annealed copper or annealed coated copper and comply with ASTM (American Society of Testing and Material) B 3, B 33, or B 189 standards.

a Conductors ( conductor ) :

The conductor area of ​​single or stranded wire should meet the requirements in Table 3.1.

b Stranding ( strand ): Use of conductors in the power cord must be Stranded (bunch stranded) or twisted cable (ropy Lay-stranded), and the minimum and the maximum diameter of the copper conductor must be by a single Table 3.2 required.

c Lay of Strands (. lay length ): Stranded twisted rope lay and pitch of not larger than Table 3.3 in claim twisting indefinite pitch direction.

2.Insulation:

The plastic material used for the power cable depends on the temperature class and the place of use, which should refer to the requirements in Table 3.13.

3.Total lay length:

The lay length should meet the requirements in Table 3.4.

4.Bonding or Grounding Conductors :

There must be ground insulation ( usually green ), its diameter must be larger or the same diameter than the diameter FireWire ( except DRT and greater than the diameter 8AWG by the ground line, can be small two AWG number ).

5.Outer cover:

The thickness of the outer cover should comply with Table 3.6~3.10 (Round Cable) and Table 5.4 (Parallel Cable), and the outer diameter should comply with Table 3.11 (Round Cable).

Integral Type and Non-integral ( Double Insulation ) Type: Currently, Nonintegral Type includes SPT-1, SPT-2, 2 to 3 cores can be used, and Integral Type has SPT-1, -2, -3, PXT and Wires such as HPN.

 6.color code:

To facilitate the identification and FireWire connection when the plumber and end product installation (Line), neutral (Neutral), and the ground (bonding), the color of the insulating layer should be consistent with Table 3.12 requirements. For example, in the case of the three-wire type, black represents the live wire, white or light gray represents the neutral wire, green or green and yellow represents the ground wire; if the product is sold in Europe (International color coding), the color can be changed to brown for the live wire, light blue Represents the neutral wire, and green and yellow represent the ground wire. Parallel lines ( such as SPT-1, HPN… etc. ) must produce ridges, lines, or use ink to identify when the neutral line (Identified) is extruded with the wire.

7.outdoor Wire & Cable:

( Such as Type SJTW, SJTOW, SJTOOW, STW, STOW, STOOW, PXWT, and CXWT Cord) It takes a long time to apply for a verification test because, in addition to the normal test, the CSA standard C22.2 No.75 must be followed. Perform a long-term insulation resistance test (Insulation Resistance at Evaluated Temperature) for at least 24 weeks or more.

What is the difference between AWM and AWG in electrical wire description?

The AWM electronic wire standard is an earlier cable standard of UL. The familiar AWM1015, 1007, 1095, etc., all come from the binder under this standard.

Many friends ask, what does 1015, 1095, 2468, and 20288 mean? In fact, a few years ago, UL cable engineers once hoped to list all cables in the world by a number of cables. In the UL758 standard, a long work was started, which was to describe the products for each kind of wire they knew, and then bind them into a book, and AWM1015 was actually a wire described on page 1015 of the binder, And so on, each model of 2468, 20288, etc. is actually a page number, and the wire of this model can be found in the corresponding page number.

  1. AWM is the abbreviation of Appliance Wiring Materials (equipment internal wiring wire) ;
  2. 1007 and 1015 are both a style of AWM ;
  3. AWG is the abbreviation of American Wire Gauge, 22AWG is equivalent to 0.324mm2 ;
  4. 1007: 80C, 300V, single conductor, single core or stranded, PVC insulation, average insulation thickness 0.38mm ;
  5. 1015: 105C, 600V, single conductor, single core or stranded, PVC insulation, average insulation thickness 0.76mm.

The terminology of wire and cable

There will be many characters on the wire and cable logo, each representing a different meaning. Here is a brief introduction to some commonly used characters:

power cable:

Parallel-Service = Thermoplastic the SPT (Service parallel thermoplastics)

= Heater Parallel Neoprene HPN (heater parallel rubber)

S = Service Service (SO, SOW, ST, STW ) O – Oil oily W is – Wet Wet T – Thermoplastic Thermoplastics

SJ = Service Junior small service (SJO, SJOW, SJT, SJTW ) O – Oil oily W is – Wet Wet T – Thermoplastic Thermoplastics

SV = Service Vacuum Cleaner cleaner (SVT, SVO) O – Oil oily T – Thermoplastic Thermoplastics

Electronic wire:

Class I internal use; Class II external use

Group A is not subject to mechanical wear; Group B is subject to mechanical wear

W: Used in a wet environment; O: Oil-proof; F: Fuel oil-proof

FT1: Vertical burning test; FT2: Horizontal burning test; FT4: Vertical burning test ( Cable in Cable tray ); FT6: Horizontal burning and smoke test.

For example: ” CSA AWM IA 90 C 300 V FT1 ” means AWM electronic wire, used internally, not subject to mechanical damage, temperature resistance 90 C, rated voltage: 300 V, and combustion class FT-1.

Requirements for factory testing

In North American electrical product certification reports, factory tests generally require a withstand voltage test. Test pressure, i.e., high-pressure test, by applying a constant high pressure between the test point to test samples tested insulation system security products can be of. Generally speaking, North American standards require 1000 V , 1 minute or 1200 V {1000 V × ( 1 + 20% ) }, 1 second withstand voltage test for 120 V products .

What does the printing on the wire printing mean?

It is not clear about the printing on the wire, such as AWM, FT1, FT2 ETL VERIFIED, I/ Ⅱ, A/B.

AWM: Appliance Wiring Material’s  electrical wire and cable wiring

FT1: FT1 burning test, the sample of the finished insulated wire or finished cable shall be evaluated in accordance with UL1581 section 1060 ; (vertical sample) burning test. The flame-retardant grade FT1 is suitable for finished wires or cables, and the insulated cores in the finished cables are graded FT1 unless otherwise specified on the sign.

FT2: FT2 burning test, the sample of the finished insulated wire or finished cable shall be evaluated in accordance with UL1581 Section 1100; Thermoplastic and rigid insulated electric cable horizontal sample burning test. The flame-retardant grade FT2 is suitable for finished wires or cables, and the insulated cores in the finished cables are graded FT1 unless otherwise specified on the sign.

ETL VERIFIED US certification

I/Ⅱ:  Internal and external wiring

A/B: A— Not evaluated B: Appraisal vibration

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