1. 电缆主绝缘的绝缘电阻测量 1. The insulation of the cable main insulation resistance measurements 1.1试验目的 1.1 test purpose 初步判断主绝缘是否受潮、老化，检查耐压试验后电缆主绝缘是否存在缺陷。 Preliminary judge whether the main insulation be affected with damp be affected with damp, aging, and check whether cable main insulation defects after pressure test. 绝缘电阻下降表示绝缘受潮或发生老化、劣化，可能导致电缆击穿和烧毁。 Insulation resistance drop said be affected with damp be affected with damp or insulation aging, degradation, may result in cable breakdown and burning. 只能有效地检测出整体受潮和贯穿性缺陷，对局部缺陷不敏感。 Can effectively detect the overall be affected with damp be affected with damp and penetrability flaw, is not sensitive to local defects. 1.2测量方法 1.2 measuring method 分别在每一相测量，非被试相及金属屏蔽（金属护套）、铠装层一起接地。 Measured respectively in each phase, the subjects and metal mask (metal sheath), armoured layer ground together. 采用兆欧表，推荐大容量数字兆欧表（如：短路电流>3mA）。 By megohmmeter, recommend the large capacity digital megohmmeter (such as: short circuit current > 3 ma). 0.6/1kV电缆测量电压1000V 。 0.6/1 kv cable to measure the voltage 1000 v. 0.6/1kV以上电缆测量电压2500V 。 More than 0.6/1 kv cable to measure the voltage 2500 v. 6/6kV以上电缆也可用5000V，对110kV及以上电缆而言，使用5000V或10000V的电动兆欧表，电动兆欧表最好带自放电功能。每次换接线时带绝缘手套，每相试验结束后应充分接地放电。 6/6 kv cable also can use 5000 v, for more than 110 kv cable, using 5000 v or 10000 v electric megohmmeter, electric megohmmeter with self-discharge function best. Every time in connection with insulating gloves, test after the end of each phase should be fully grounding discharge. 电动兆欧表 Electric megohmmeter 1.3试验周期 1.3 the test cycle 交接试验 Commissioning test 新作终端或接头后 After the new terminal or joint 1.4注意问题 1.4 pay attention to the problem 兆欧表“L”端引线和“E”端引线应具有可靠的绝缘。 "L" and "E" lead by megger end should have reliable insulation. 测量前后均应对电缆充分放电，时间约2－3分钟。 Both before and after the deal with cable fully discharge, measured time about 2 to 3 minutes. 若用手摇式兆欧表，未断开高压引线前，不得停止摇动手柄。 If use manual megohmmeter, before disconnect high-voltage wire, must not stop shaking the handle. 电缆不接试验设备的另一端应派人看守，不准人靠近与接触。 Cable does not connect the other end of the test equipment should be sent to guard, are not allowed to be close to and contact. 如果电缆接头表面泄漏电流较大，可采用屏蔽措施，屏蔽线接于兆欧表“G”端。 If the cable joint surface leakage current is larger, can use shielding measures, shielded wire connected into megohmmeter "G". 1.5主绝缘绝缘电阻值要求 1.5 the main insulation insulation resistance value 交接：耐压试验前后进行，绝缘电阻无明显变化。 Transition: before and after the pressure test, insulation resistance has no obvious change. 预试：大于1000MΩ Pilot test: greater than 1000 m Ω