Instruments: [Question of the Week] Week 26, 2011: What is isolation? Under what circumstances should isolation be used for measurements?
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This post was last edited by siena2008 on 2011-7-12 at 10:44. Topic: What is isolation? When should isolation be used for measurements? Isolation is a method that involves using isolation fluid or diaphragms to prevent direct contact between the medium being measured and the instrument components, thereby protecting the instrument and enabling accurate measurement. For corrosive media, when the material of the measuring instrument does not meet the corrosion resistance requirements, isolation can be used to protect the instrument. For viscous media, media containing solids, toxic media, or media that may vaporize, condense, crystallize, or precipitate at ambient temperature, isolation can also be employed to enable measurement.
It involves separating the medium from the measuring instrument using an isolation fluid. For heavy oil media and toxic and harmful media, isolation is required.
Signal isolation, between the field and the control cabinet
Isolation is a method that uses isolation fluid and isolation diaphragms to prevent the medium being measured from coming into direct contact with the instrument components, thereby protecting the instrument and enabling accurate measurement. For corrosive media, when the material of the measuring instrument does not meet the corrosion resistance requirements, isolation should be used to protect the instrument. For viscous media, media containing solids, toxic media, or media that may vaporize, condense, crystallize, or precipitate at ambient temperature, isolation can be employed to enable measurement.
This post was last edited by denghl on 2012-12-21 at 21:16. The function of isolation is, in terms of systems, to separate dangerous currents from the system and prevent it from being subjected to excessive loads that could cause fluctuations. For field instruments, it serves to avoid sparks resulting from electrical short circuits, which could lead to explosions when in contact with flammable gases. For example, in the case of field transmitters, isolation can also be understood as preventing corrosive or highly viscous media from affecting the diaphragm box; to reduce measurement inaccuracies, isolation sleeves can be used.
Isolation of the medium from the sensor to protect the sensor
A blow-type differential pressure level gauge can also serve as an isolation protection mechanism when measuring the level of highly corrosive liquids.
The last edit to this post was made by denghl on 2012-12-21 at 21:20; isolation is used when the medium does not allow direct contact between the measuring elements
This post was last edited by denghl on 2012-12-21 at 21:21. Isolation is a method of using isolation fluid or diaphragms to prevent the medium being measured from coming into direct contact with the instrument components, thereby protecting the instrument and the measurement process. For corrosive media, viscous media, media containing solids, toxic media, or media that may vaporize, condense, crystallize, or precipitate at ambient temperature, isolation can be implemented to enable measurement.
Isolation between the field signals and the control cabinet?
Reply to 10# FNlongD: This isolation should be for measurement purposes; of course, the system also has isolation safety barriers