First, the meaning of various commonly used letters
R-connecting flexible cable (wire), soft structure. V-insulated PVC. V-PVC insulation V-PVC sheath B-flat (flat). S-twisted type. A-tin or silver plating. F- high temperature P-bracketed shield P2- copper tape shield P22-steel tape armored
Y-prefabricated, generally omitted, or polyolefin sheathed FD-product category code, refers to the branch cable. The Ministry of Construction standards to be promulgated are represented by FZ, which are essentially the same YJ-XLPE insulated V-PVC insulated or sheathed ZR-flame-retardant NH-refractory WDZ-Halogen-free low-smoke flame retardant WDN-None Halogen low smoke refractory type
Second, cable knowledge
Cables are usually divided into power cables and control cables.
1, the meaning of the cable symbol:
[1]ZR-Flame Retardant, NH-Fire-Resistant, ZA(IA)-Intrinsically Safe
[2] use. Power cable default representation, K-control cable, P-signal cable, DJ-computer cable
[3] Insulation. V-polyvinyl chloride, Y-polyethylene, YJ-crosslinked polyethylene, X-rubber, Z-paper
[4] Conductors. The T-copper core defaults to the L-aluminum core.
[5] Inner sheath (sheath), V-PVC, Y-polyethylene, Q-lead, L-aluminium, H-rubber, HF-non-combustible rubber, LW-wrinkle aluminum sheath, F - Neoprene, N-butyl rubber sheath.
[6] Features. Do not need to indicate that the package type, F-phase lead-phased phase-separated jacket, D-no oil, CY-oil, P-shielded, C-filter, Z-DC
[7] Armored layer. 0-None, 2-double strip (24-steel strip, thick round wire), 3-thick round wire, 4-thick round wire (44-double round wire).
[8] The outer layer. 0-None, 1-fiber layer, 2-PVC sheath, 3-PE sheath.
[9] Rated voltage. Expressed in numbers, kV.
2, examples of commonly used cables:
VV copper core PVC insulated PVC sheathed power cable.
VV22 copper core PVC insulated PVC sheathed power cable .
YJV XLPE insulated, PVC sheathed power cable
3, the meaning of the specification
Specifications using the number of cores, nominal cross section and voltage level
1 Specification of single-core branch cable: Number of cables in the same loop*(1*nominal section), 0.6/1KV,
For example: 4*(1*185)+1*950.6/1KV
2 Multi-core stranded branch cable specification notation: number of identical loop cables* nominal cross section, 0.6/1KV,
For example: 4*185+1*950.6/1KV
Third, wire knowledge
1, the general meaning of the wire symbol:
[1] Code. B-wire (sometimes not indicated)
[2] Conductors. T-copper (default), L-aluminum, R-soft copper
[3] Insulation. V-PVC, X-rubber, F-chloroprene rubber
[4] Sheath. V-polyvinyl chloride
[5] Others. R-soft wire, P-shielded, B-parallel
2, examples of commonly used wires:
(1), BX, BLX: rubber insulated wire. Fixed laying in indoor or outdoor, bright, dark or wear pipe, as equipment installation line.
(2), BXF, BLXF: neoprene insulated wire. With BX type, good weather resistance, suitable for outdoor use.
(3), BXHF, BXLHF: Rubber insulated and sheathed wires. With the BX type, it is suitable for humid places and as an outdoor entrance line.
(4), BV, BLV: PVC insulated wire. Same type BX, but better moisture resistance and weather resistance.
(5), BVR: PVC insulated soft wire. The same type BV is only used for soft installation.
(6), BV-10 V, BLV-105: heat-resistant 105 °C PVC insulated wire. Same as Type BV, used in high temperature environments of 45°C and above.
(7), BVR-105: heat-resistant 105 °C PVC insulated soft wire. With BVR type, used in high temperature environments of 45°C and above.
Fourth, video file transmission material (such as: cable TV) knowledge
Video file signal transmission cable. There are roughly three kinds of coaxial cables, twisted pairs, and optical fibers.
Describe the commonly used coaxial cable knowledge:
1. Classification of Coaxial Cables: Coaxial cables for video file transmission are SYV75-III, SYV75-V, SYV75-7, SYV75-9, SYV75-12
2, the meaning of the letters:
SYV75-5-1 (A, B, C)
SYV75-5-41 (A, B, C)
SYV75-5-2 (A, B, C)
S stands for RF coaxial cable
Y represents polyethylene (PE) insulation
V stands for polyvinyl chloride (PVC) jacket
75 stands for characteristic impedance 75 ohms
5 represents the approximate value of the insulating outer warp
-1, -41 or -2 represents the structural form code. General -1 or -41 represents the inner conductor is single-core; -2 represents the inner conductor is multi-core
A: 64 series B: 96 series C: 128 series