一) 电力电缆的表示方法 ( I ) Representation method of power cable
电缆型号的表示方法 1.Indication method of cable model
规定用拼音字母和数字组合来表示电缆的类别和型号。 In order to accurately indicate the use, structure type and name of the cable, the national standard GB / T2952—1989 stipulates that the type and model of the cable are represented by a combination of pinyin letters and numbers. Models are usually represented by uppercase Chinese pinyin letters, and cable insulation and inner and outer protective layers are represented by a combination of pinyin letters and numbers, which can not only completely reflect the type and use of the cable, but also the main structure, materials, and laying occasions of the cable Such characteristics are clear.
表示阻燃系列， NH-表示耐火系列。 Note: Add the pinyin letter ZR- before the cable model to indicate the flame-retardant series, and NH- to indicate the fire-resistant series.
二) 电力电缆的分类 ( B ) the classification of power cables
塑料 )电力电缆、交联聚乙烯绝缘电力电缆 、橡皮绝缘电力电缆 、充油及油浸纸绝缘电力电缆 ，按工作类型和性质可分为一般普通电力电缆、架空用电力电缆、矿山井下用电力电缆、海底用电力电缆、防(耐)火阻燃型电力电缆等类型。 Power cables are generally divided into PVC insulated ( plastic ) power cables, XLPE insulated power cables , rubber insulated power cables , oil-filled and oil-impregnated paper insulated power cables according to their insulation types. General power cables , overhead power cables, underground mine power cables, submarine power cables, fire-resistant ( fire-resistant ) flame-retardant power cables and other types.
三)几种常用电缆及其特性 ( Three ) several commonly used cables and their characteristics
铜芯导体电力电缆 Copper conductor power cable
At present, domestic low-voltage power cables are all stranded together. The cable of this structure has poor anti-interference ability and poor lightning strike resistance. The three-phase impedance imbalance and large zero-sequence impedance of the cable are difficult to protect the line. The appliance operates reliably, etc.
交联聚乙烯绝缘电力电缆 2. XLPE insulated power cable
电缆，它是利用化学或物理的方法使电缆的绝缘材料聚乙烯塑料的分子由线型结构转变为立体的网状结构，即把原来是热塑性的聚乙烯转变成热固性的交联聚乙烯塑料，从而大幅度地提高了电缆的耐热性能和使用寿命，仍保持其优良的电气性能。 Referred to as XLPE cable, it uses chemical or physical methods to change the molecular structure of the cable's insulating material, polyethylene plastic, from a linear structure to a three-dimensional network structure, that is, to convert the originally thermoplastic polyethylene into a thermosetting crosslinked polyethylene. Plastic, which greatly improves the heat resistance and service life of the cable, while still maintaining its excellent electrical properties.
聚氯乙烯绝缘聚氯乙烯护套电力电缆 3.PVC insulated and PVC sheathed power cable
℃，电缆导体的最高温度不超过160 ℃。 The long-term working temperature of the PVC insulated and PVC sheathed power cable does not exceed 70 ℃, and the maximum temperature of the cable conductor does not exceed 160 ℃. 不超过5s ，施工敷设最低温度不得低于0 ℃ The longest duration of the short circuit does not exceed 5s , and the minimum temperature for construction and laying should not be lower than 0 ℃