Question regarding the notation format of thermocouples in PID
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Our PID drawings show that there are two tag numbers for the thermocouples. What is the difference between TE10716 and TI10716? My personal interpretation is that TE is a component on-site that displays the values locally, whereas TI are the values displayed locally which are transmitted to the DCS via electrical signals. Is this explanation correct? I would appreciate the guidance from all experts!
TE 10716 refers only to the thermocouple element; it has no on-site display, while TI 10716 refers to the DCS display, right?
Refer to HG/T 20505-2014 for the functional indicators and graphic symbols of process measurement and control instruments
TE refers to the on-site primary temperature sensing element, while TI is the DCS display.
You can’t just look at the letters; you also need to consider circles, squares, diamonds, and horizontal lines as well
The letter E in TE 10716 merely denotes the detection element, the primary component (that is, the sensor), and has no indicative meaning. The line connecting TE 10716 and TI 10716 is a dashed line, indicating an electrical signal; in other words, TE 10716 sends an electrical signal (in millivolts) to the DCS in the control room to display the temperature corresponding to 10716.
TE on-site inspection TI DCS display
This post was last edited by xxkhc on 2017-12-4 at 16:36. The first circle is an illustration of on-site installation; T represents temperature, and E represents the sensing element； The second box with a circle and a horizontal line represents installation in the control room (or DCS); T stands for temperature, and I stands for indication. 10716 is the tag number.
The working principle of a high-temperature thermocouple is to convert temperature signals into electrical signals that can be recognized by a computer; in other words, the thermocouple functions as a device for converting temperature signals into electrical signals
TE refers to on-site temperature sensing elements such as thermocouples; TT represents temperature variation; TI is the tag number shown in the control system flow diagram