Control cables belong to electrical equipment cables, and power cables are two of the five categories of cables. The color of the insulated core of the control cable is generally black with white characters, and the low voltage of the power cable is generally color separated. The cross section of the control cable is generally not more than 10 square meters, and the power cable is mainly used to transmit power, which is generally a large cross section. The cross-section of the control cable is generally small, and the maximum is generally not more than 10 square meters. Control cable transmission control signal, the number of cores is more, according to the standard, there are more than 61 cores, but it can also be produced according to user requirements.

Main product of control cable

Cables connected from the control center to each system to transmit signals or control operational functions are collectively referred to as control cables. The early functions of the control cable are relatively simple, including: indicator light display, instrument indication, relay and switchgear operation, alarm interlock system. In recent years, due to the wide application of weak current and computer network, new functions and higher requirements have been put forward for the selection and application of control cables. In this paper, some new problems in the selection and use of control cables in recent years are discussed for reference.

The main products of the control cable are: polyvinyl chloride insulated control cable, natural - styrene butadiene rubber insulated control cable and polyethylene insulated control cable three series. In addition, there are crosslinked polyethylene insulation and ethylene propylene rubber insulation products. The oil-impregnated paper-insulated lead-covered control cables produced in the early years have been eliminated.

National standard GB50217-91

In order to ensure that the control cable in the event of insulation breakdown, mechanical damage or fire, reduce the scope of the spread, the national standard GB50217-91 "Electric power engineering cable design code" stipulates: dual protection of the current, voltage and DC power supply and trip control loop need to enhance the reliability of the two sets of systems, should use their own independent control cables.

For example, an ultra-high voltage substation split phase operation circuit breaker control loop, three phases with a cable, there has been such an accident, by the split phase operation of the pulse to trigger other phases of the thyristor, resulting in three-phase linkage, after the use of separate independent cables, there is no misoperation accident. Another example is the computer monitoring system of a power plant, because the analog low level signal line and the transmitter power line are combined with a four-core cable, which has caused 70V interference voltage in the signal line, which will obviously affect the normal operation of the low-level signal loop measured in millivolts.

Measures to prevent or mitigate electrical interference

There are mainly the following three aspects

1. A spare core of the control cable is grounded

2, the circuit that will have serious consequences for electrical interference is not suitable for a control cable

3. The metal shield is grounded with the shield layer

Qingdao Tianxing Cable Co., Ltd. is a technology enterprise specializing in the production of wire and cable in Shandong Province, with more than 150 sets of domestic excellent cable production equipment and testing equipment, excellent production technology, modern testing equipment, to ensure stable product quality and timely supply. The company's main products are power cable, mineral cable, high life wire and cable, radiation crosslinked cable, control cable, computer cable, photovoltaic cable, communication cable, data cable, low smoke halogen free cable, flame retardant series wire and cable.