JC-OM700-EE Wireless Expansion Joint Sensor

Product Introduction

JC-OM700-EE Wireless Expansion Joint SensorBy modifying the existing mechanical vernier caliper of the GIS/GIL expansion joint or adding a digital expansion joint displacement sensor, the compensation amount of the expansion joint can be monitored online. The wireless expansion joint sensor uses a high-speed ARM chip as the main control and a high-precision displacement sensor to real-time sample and calculate the displacement data of the measured object. The data can be uploaded to the upper computer through wireless LoRa and wired RS485.

Main configuration list of the system

JC-OM700-EE Wireless Expansion Joint SensorProvided a reliable online monitoring solution for GIS/GIL equipment. This product adopts high-precision displacement sensing technology, combined with ARM processor, which can accurately measure the displacement changes of expansion joints. In terms of communication, it supports LoRa wireless and RS485 wired dual-mode transmission to meet the networking needs of different on-site environments. The product design emphasizes practicality, has low operating power consumption, and can support long-term stable operation. For special working conditions, multiple protection models are available, including versions that are suitable for low temperatures, dust-proof, and corrosion-resistant. The system has been practically applied in multiple power engineering projects, and the installation method is compatible with existing mechanical verniers, which helps to achieve continuous monitoring of equipment status. Compared to traditional manual inspections, this monitoring method can provide more timely data feedback and provide reference for equipment maintenance.

construction objectives

GIL is a gas insulated metal enclosed transmission line, mainly composed of equipment such as pipeline busbars and expansion joints. Among them, the pipeline busbar is an important component of GIL, and its length is generally several kilometers. The expansion joint, as an accessory equipment of the pipeline busbar, is mainly used for length adjustment and compensation during the installation of GIL equipment, as well as compensation for changes in the compensation amount of the pipeline busbar cylinder with seasonal and environmental temperature changes after operation. The length of the GIL pipeline busbar will vary with the change of environmental temperature. If the GIL expansion joint cannot adjust the compensation amount due to installation or manufacturing process problems, it may cause deformation and leakage of the connection part of the GIL equipment due to expansion stress. When the displacement of the expansion joint is large, it cannot be detected in a timely manner, which may lead to hidden dangers. In severe cases, it may cause insulation breakdown of the equipment. Therefore, monitoring the compensation amount of the GIL expansion joint is an important project for the daily operation and maintenance of GIL equipment.

State Grid Corporation of China stated in 12.2.1.3 of the 2018 version of the anti accident measures that "GIS manufacturers should provide engineering expansion joint configuration plans during equipment bidding, data confirmation, and other stages, and should be included in the review content of the Engineering Design Joint Committee. The plan includes adjustment parameters such as the type, quantity, location, and corresponding detailed table of "expansion joint (status) expansion amount - environmental temperature" for each expansion joint. Expansion joints should be installed at different foundations for outdoor installations and expansion joints for indoor installations.

In the early design of GIL pipe gallery expansion joint compensation monitoring, the compensation amount of expansion joints was mainly based on the inspection of operation and maintenance personnel and maintenance personnel. The maintenance personnel recorded the compensation amount of expansion joints in real time according to the installation of vernier calipers on site, and compared it with experience and past data to determine whether the compensation amount of expansion joints was reasonable. However, these methods cannot achieve real-time monitoring of the compensation amount of expansion joints and cannot fundamentally solve hidden dangers; Moreover, due to the high height of the expansion joints in the middle and upper parts of the pipe gallery, manual inspection is difficult. Therefore, designing an online monitoring system for the live operation status of the expansion joints is of great significance for real-time online monitoring of the compensation amount of the expansion joints.

technical route

Using the existing mechanical vernier caliper in the GIL pipeline gallery, manual inspection is required. It is now necessary to add online displacement monitoring sensors to monitor the compensation amount of the expansion joint online.

Expansion joint expansion displacement sensor is a new type of digital displacement sensor, which is a linear device belonging to metal induction. The function of the sensor is to convert various measured physical quantities into electrical quantities. By fully combining the advantages of angle sensors and linear displacement sensors, it has become a sensor with small installation size, compact structure, large measurement stroke, and high accuracy, with a stroke ranging from a few hundred millimeters to tens of meters.

Online monitoring of expansion joint compensation can be achieved by modifying existing mechanical vernier calipers or adding digital expansion joint displacement sensors.

technical indicators

Power supply method: lithium battery or 12V power supply

Service life: Over 5 years

Static power consumption:<=10uA

Working environment: -25~60 ℃; Average humidity ≤ 90% (no condensation)

Sampling frequency: default 30 minutes

Wireless modulation method: LORA or RS485

Wireless transmission distance: ≤ 500 meters

Installation method: snap on type

Dimensions: Customized

Technical Solution

The expansion joint compensation device can use LORA wireless communication or RS485 wired communication, and can be powered by batteries. The monitoring device is designed with low power consumption, and the wireless collector of the monitoring system uses LORA wireless communication or RS485 communication below, and MODBUS or IEC 61850 communication above.

Network architecture diagram of expansion joint compensation monitoring device

On site installation diagram

Installation diagram of pull rope sensor on site Installation diagram of pull rod sensor on site

Soft works and patents

Soft Work 4 Invention 4 Appearance Design 1

Inspection Report

Production, testing, shipping, and on-site installation photos

Production testing and shipping

on-site installation

Project Case

1. 1000kV Sutong GIL comprehensive pipe gallery project

2. 500kV Suzhou Mudu Substation

3. State Grid Jiangsu Ultra High Voltage Company's UHV Center 800kV Gusu Converter Station Equipment Management Platform

4. 500kV Sunan UPFC Station

5. Shanxi Jincheng 220kV Jinding Substation