The meaning of the cable specification model

Model meaning:

R-Flexible cable (wire) for connection, soft structure.

V-Insulation PVC. V-PVC insulation 　　 V-PVC sheath

B-Flat (flat).

S-twisted pair type. A-tin or silver plated.

F－High temperature resistance

P-braided shield 　　 P2-copper tape shield 　 P22-steel tape armor

Y—prefabricated type, generally omitted, or polyolefin sheath

FD—product category code, refers to branch cables. The Ministry of Construction standards to be promulgated are denoted by FZ, which are essentially the same

YJ—cross-linked polyethylene insulation

V—Polyvinyl chloride insulation or sheath

ZR—flame retardant

NH—Refractory

WDZ—halogen-free low-smoke flame retardant

WDN—halogen-free low-smoke refractory

For example: SYV 75-5-1 (A, B, C)

S: Radio frequency Y: Polyethylene insulation V: Polyvinyl chloride sheath A: 64 series B: 96 series C: 128 series

75: 75 ohm 5: wire diameter is 5MM 1: represents single core

SYWV 75-5-1

S: RF Y: Polyethylene insulation W: Physical foaming V: Polyvinyl chloride sheath

75: 75 ohm 5: The outer diameter of the cable is 5MM 1: Represents single core

For example: RVVP2*32/0.2 RVV2*1.0 BVR

R: Flexible wire VV: Double-sheathed wire P shield

2: 2-core multi-stranded wire 32: Each core has 32 copper wires 0.2: Each copper wire has a diameter of 0.2MM

ZR-RVS2*24/0.12

ZR: Flame-retardant R: Flexible wire S: Twisted pair

2: 2-core multi-stranded wire 24: Each core has 24 copper wires 0.12: Each copper wire has a diameter of 0.12MM

Model Name

RV copper core vinyl chloride insulated connection cable (wire)

AVR tinned copper core polyethylene insulated flat connection flexible cable (wire)

RVB copper core PVC flat connection wire

RVS copper core PVC stranded connecting wire

RVV copper core PVC insulated PVC sheathed round connecting flexible cable

ARVV tinned copper core PVC insulated PVC sheathed flat connecting flexible cable

RVVB copper core PVC insulated PVC sheathed flat connecting flexible cable

RV－105 Copper core heat-resistant 105oC PVC insulated PVC insulated flexible connecting cable

AF－205AFS－250AFP－250 Silver-plated polychloroethylene fluoride plastic insulated high temperature resistant －60oC~250oC connecting flexible wire

2. The meaning of specification notation

Specifications are expressed by core number, nominal cross section and voltage level

①Single-core branch cable specification representation: the number of cables in the same loop* (1*nominal section), 0.6/1KV,

Such as: 4*(1*185)+1*95 0.6/1KV

②Specification of multi-core stranded branch cable: number of cables in the same loop * nominal cross section, 0.6/1KV,

 Such as: 4**185+1*95 0.6/1KV

③Specification method of multi-core branch cable with same sheath: number of cable cores×nominal section-T, such as: 4×25-

Estimation of current carrying capacity of insulated wires

The relationship between current-carrying capacity and cross-section of aluminum core insulated conductor

Conductor section (mm 2) 1 1.5 2.5 4 6 10 16 25 35 50 70 95 120

Carrying current is a multiple of section 9 8 7 6 5 4 3.5 3 2.5

Carrying capacity (A) 9 14 23 32 48 60 90 100 123 150 210 238 300

Estimation formula: multiply by nine by 2.5 and go up and minus one. Thirty-five times three and five, both in groups minus five. The conditions are changed and the conversion is added, and the high temperature 10% copper upgrade. The number of piercing pipes is two, three, four, and eight or seventy-six percent full load current.

Explanation: (1) The formula in this section does not directly indicate the current carrying capacity (safe current) of various insulated wires (rubber and plastic insulated wires), but "cross-section multiplied by a certain multiple", which is obtained through mental calculation. It can be seen from Table 53: The multiple decreases with the increase of the cross section. "Two-and-a-half times down by nine, going up and down by one" refers to aluminum core insulated wires of various cross-sections of 2.5 mm’ and below, and their current carrying capacity is about 9 times the number of cross-sections. For example, 2.5mm' wire, the current carrying capacity is 2.5×9=22.5(A). The multiple relationship between the current-carrying capacity and the number of cross-sections of wires from 4mm’ and above is to line up along the wire number, and the multiples are successively reduced by l, namely 4×8, 6×7, 10×6, 16×5, 25×4. "Thirty-five times three and five, two pairs into groups minus five points", it is said that 35mm" the current carrying capacity of the wire is 3.5 times the number of sections, that is, 35 × 3.5 = 122.5 (A). For wires of 50mm' and above, the multiple relationship between the current-carrying capacity and the number of cross-sections becomes a set of two wire numbers, and the multiples are reduced by 0.5. That is, the current-carrying capacity of 50 and 70mm' wires is 3 of the number of cross-sections. The current carrying capacity of 95, 120mm" conductor is 2.5 times of its cross-sectional area, and so on. "Conditions have changed, plus conversion, high temperature 10% copper upgrade."

The above formula is determined by the aluminum core insulated wire and the open coating at an ambient temperature of 25°C. If the aluminum core insulated wire is exposed to the area where the ambient temperature is higher than 25℃ for a long time, the current carrying capacity of the wire can be calculated according to the above formula calculation method, and then a 10% discount is enough; when the copper core insulated wire is not used, Its current-carrying capacity is slightly larger than that of the aluminum wire of the same specification. According to the above formula, the current-carrying capacity of one wire larger than the aluminum wire can be calculated. For example, the current carrying capacity of 16mm’ copper wire can be calculated as 25mm2 aluminum wire