
This product is suitable for electronic computers with rated voltage of 500V and cables with high requirement of anti-interference. Type K B low density polyethylene with anti-oxidation property is adopted for insulation of cable core. Polyethylene high insulation resistance, good resistance to voltage, small dielectric coefficient and temperature and the influence of variable frequency dielectric loss is small, can not only meet the requirements of transmission performance, and can ensure the service life of the cable. In order to reduce crosstalk and external interference between circuits, the cable adopts shielding structure. The shielding requirements of cables are respectively adopted according to different situations, such as the method of shielding the hinged combination, the method of shielding the hinged combination, and the method of shielding the hinged combination after the hinged combination. Shielding materials are round copper wire, copper belt, aluminum belt/plastic composite belt three. Shielding pair and shielding pair have good insulation performance. If there is potential difference between shielding pair and shielding pair, the signal transmission quality will not be affected.

Oil filled telecommunication cable identification and marking: cable outer surface sexual identification mark, mark at no more than alternate 1 m intervals, tag contents are: the diameter of wire, line number, cable type, factory name and year of manufacture, marking at no more than alternate 1 m intervals to mark on the surface, but with the tag stagger.
This product is suitable for connecting cables and electrical instrumentation and automatic control of the transmission line, it is compared with the ordinary plastic insulated control cables, insulation using fluorine plastic, product is higher than normal control cable temperature classification, oil resistance, waterproof, wear-resistant, resistant to corrosive gas, ageing resistance, best can, is mainly used in metallurgy, electric power, petrochemical and other industries with special requirements such as heat resistance.
DJYP3VP3R 聚乙烯绝缘对绞铝塑复合带分屏蔽及总屏蔽聚氯乙烯护套软计算机电缆 敷设室内、电缆沟、管道等要求静电屏蔽场合。
DJYPV22 聚乙烯绝缘对绞铜线编织分屏蔽聚氯乙烯护套钢带铠装计算机电缆 敷设室内、电缆沟、管道等要求静电屏蔽并承受较大机械外力固定场合。

3、产品标准:GB9330.2-88《聚氯乙烯绝缘和护套控制电缆》大对数HYA、市内通信电缆(主要技术指标HYAHYACHYA22HYA23HYA53执行标准:YD/T电缆芯数(规格) 电缆芯径直径 绝缘最大偏心(mm) 绝缘抗压缩力(N) 绞合节距(mm) 近端串音衰减 远端串音防卫度 备注:HY。
PLC控制是个永远学不完的行业,不同的品牌和系列,有不同的编程方法和指令,有不同的硬件控制方法。
譬如日本三菱plc和德国西门子plc,属于日系和德系,编程指令和硬件都有很大的不同。
自动化控制就是不断学习的过程。
有个好的老师。
真正开始学习,感觉自己研究10天,还不如老师2分钟的指点。
像我刚开始学习PLC,继电器研究1周多,还没有搞明白是怎么用。
有个好老师可以节省很多时间。
Flame retardant performance: under specified test conditions, specimen was burning, after removed test of ignition, flame spread only in a limited range, residual flame or residual burning characteristics of self extinguishing reaction in the limited time.
Low smoke and low halogen flame retardant control cables are suitable for the use of ac rated voltage 450/750v and below control, monitoring circuit and protection line with certain environmental protection requirements. Operating conditions (1) rated voltage U0/U is 450/750v; (2) the cable conductor allowed to work at 70 ℃ for a long time; (3) the cable temperature under installation should not below 0 ℃, allowed bending radius; recommended by (4) the cable without armor layer shall be no less than 6 times the outer diameter of the cable; (5) the cable with armored or copper belt shielding structure shall be no less than 12 times the outer diameter of the cable; (6) the soft cable with shield layer structure shall be no less than 6 times of the cable. Technical requirements for 20 ℃ dc resistance conductors shall comply with the terms of GB9330.1 insulation resistance are shown in table 3 - table 6. The fire retardant performance test of the cable conforms to the provisions of GB/T18380. If the user does not require it to meet the requirements of class C fire retardant. The cable smoke concentration shall comply with the provisions of GB/T17651, and its light transmittance shall be 60%. The halogen content should not exceed 100 mg/g. Other performance requirements are the same as GB9330.
表3导体标称截面mm2导体结构(根数/单丝直径mm)ABR0.51/0.87/0.3016/0.20.751/0.977/0.3724/0.21.01/1.137/0.4332/0.21.51/1.377/0.5230/0.252.51/1.767/0.6849。
Flame retardant cables and fireproof cables: the difference between the average person is very easy to confuse the concept of flame retardant cables and fireproof cables, although there are many more flame retardant cable applies to the advantages of chemical enterprise, such as low, low smoke, non-halogen, but in general, fire-resistant cable can replace flame retardant cable, and flame retardant cables can't take place of fire-resistant cable.

MHYV cable, communication cable for mine use, mine cable, communication cable, mine cable for mine use, MHY32 cable, PUYV cable, MHYVP cable, MHYVR cable, flame retardant coal mine in communication cable, cable, mine monitoring cable, PUYVR cable, mine telephone lines, cable for mine monitoring, mine, mine telephone cable, execution: the enterprise standard Q/TX002-2006 is suitable for the coal mine with copper together flame retardant sheath fixed and class communication cable. MHYBV(PUYBV) coal mine with poly-insulated galvanized steel wire braided armor fire retardant poly-chloride sheath communication cable 5-50
RS485 bus due to its wiring is simple, stable and reliable and widely used in video surveillance, access control intercom, building alarm and other fields, however, because there are a lot of in the process of 485 bus wiring is not completely accurate concept leads to many problems. Some wrong ideas will now be clarified.
不允许用万用表R×R×10挡测量微安表、检流计、标准电池等的内阻。
g。
测量间歇时,应防止两根表棒短路,浪费电池能量。
测量电流、电压时应注意以下七点。
a。
测量电流时,万用表串人电路,红色表棒接被测对象正极,黑色表棒接被测对象负极。
b。
测量电压时,万用表并人电路,红色表棒接被测对象高电位,黑色表棒接至低电位。
c。
测试中需转换量程时,应将表棒离开测试点,以免转换开关因接触点打火而被烧毁。
d。
若不知被测对象的大小,应先将万用表放置在最大测量量程,视指针偏转情况再逐步减小测量量程。
1. The cable conductor of long term working temperature should be allowed no more than 70 ℃, in the process of using cable should prevent high temperature radiation or contact; Cable laying ring

加“ia、I、ZRI、IZ”是本安,加“N、NA、NH”是耐火、加(T、D)是对绞形式、屏蔽:P铜网屏蔽、P1镀锡屏蔽、P2铜箔屏蔽、P3铝箔屏蔽、PL铝箔屏蔽、P22屏蔽带铠装、P2/22铜箔屏蔽带铠装,耐压等级有:300/500V、300/300V、-0.5KV、-0.75KV、450/750V。
The flame retardant control cable passed iec332-3 wire and cable bunching test, in which the ZRC cable passed iec332-3c bunching test (class C should make the total volume of combustible materials 1.5L/M and the flame time 20min). The ZRA cable passed the iec332-3a beam forming test (the total volume of combustible materials should be 7L/M, and the flame time should be 40min). Class A flame retardant performance is superior to class C flame retardant performance.
The main products of communication cables are HYA, HYAC, HYAT, HYAT53 and HYA53