摘要
仪表设计规范中,要求仪表电缆屏蔽层做单端接地,不允许做多点接地。随着数字通信技术的发展和全厂等电位连接的全面实施,多点接地屏蔽能力在电缆信号的电磁兼容性上比单端接地强得多。通过分析单端接地和多点接地的不同,对FF和Profibus两种现场总线的屏蔽接地要求进行了对比,对现场总线及通信信号屏蔽接地的做法和要求提出了新的建议和思路。
According to the design code of instrument,the cable shield is required to be grounded as single-point grounding,while multi-point grounding is not permitted.With the development of digital communication technology and the implementation of equipotential grounding in the whole plant,multi-point grounding is proved to be much better shielding than that with single-point grounding in the electromagnetic compatibility.Through analyzing the difference on grounding ways of single-point and multi-point,the requirements on shielding grounding for the two fieldbus of FF and Profibus are compared.Some proposals and new ideas on the choice and requirement on fieldbus and shield grounding for communication grounding are put forward.
作者
王华
陈鹏
Wang Hua;Chen Peng(Hualu Engineering & Technology Co.Ltd.,Xi'an,710065,China)
出处
《石油化工自动化》
CAS
2019年第5期13-18,共6页
Automation in Petro-chemical Industry
关键词
屏蔽接地
等电位连接
接地系统
电磁兼容
单端接地
多点接地
现场总线
shielding grounding
equipotential grounding
grounding system
electromagnetic compatibility
single-point grounding
multi-point grounding
fieldbus
