High voltage transmission switching apparatus with gas monitoring device

摘要

A high voltage switching apparatus 10 is described containing an arc-quenching gas containing sulphurhexafluoride in a vessel 12 that is monitored by a gas monitoring device 20. A temperature transducer 34 is attached to the exterior of the vessel 12 to sense the temperature of the gas. A gas line 24 leads from a control panel 18 to an enclosure 22 of the device 20. The device 20 has a front display panel with a digital communication terminal 42 for connecting to a computer to load and download data to and from the device 20 relating to the density of the gas within the vessel 12. The device 20 includes a data input module 44, a control module 46, a relay module 48, a display module 50 and a DC power supply module 52 mounted in an enclosure 22. The enclosure 22 has an internal heater 56 for maintaining the temperature within the enclosure above 20 DEG C. The control module 46 has a microprocessor 70 that is program controlled to poll the transducers and calculate the present density of the gas and determine if the density has sufficient deviation to warrant the activation of a series of relays. Additionally, the microprocessor 70 is programmed to record the events that occur to the device as a historical record that may be later downloaded.