Temperature transmitter symbol
Also called TT
A temperature transmitter turns the reading from a temperature element, a thermocouple or RTD, into a signal for the control system.
What the temperature transmitter symbol means
A temperature transmitter turns the reading from a temperature element, a thermocouple or RTD, into a signal for the control system.
How it is drawn
A field instrument circle tagged TT, connected to a thermowell in the line.
The temperature transmitter symbol in each standard
Drawn as ISA 5.1 defines it, as on most US and international legends.
ISO 10628-2 does not cover instruments. On ISO-based P&IDs they are drawn as IEC 62424 PCE requests, or to ISA 5.1 on many international projects.
German (DIN): Temperaturmessumformer. See DIN P&ID symbols.
Where you see it on a P&ID
On heat exchangers, reactors, compressors and fired heaters.
Tag codes
The temperature transmitter is commonly tagged:
- TT
- TE
- TW
Tag formats follow the project numbering procedure. For instruments, the letters follow ISA 5.1, explained on the instrument symbols page.
Related symbols
Frequently asked questions
What does the temperature transmitter symbol look like on a P&ID?
A field instrument circle tagged TT, connected to a thermowell in the line.
What is a temperature transmitter used for?
A temperature transmitter turns the reading from a temperature element, a thermocouple or RTD, into a signal for the control system. You will find it on heat exchangers, reactors, compressors and fired heaters.
What tag does a temperature transmitter have?
It is commonly tagged TT, TE, TW. The exact tag format comes from the project numbering procedure and the legend sheets.
Is the temperature transmitter symbol the same in ISA and ISO?
ISO 10628-2 does not cover instruments. On ISO-based P&IDs they are drawn as IEC 62424 PCE requests, or to ISA 5.1 on many international projects. Companies vary the details, so always check the legend sheets at the front of the P&ID set.
What is the temperature transmitter called in German?
Temperaturmessumformer. On a German R&I-Fließschema it is drawn to DIN EN ISO 10628-2 and DIN EN 62424.
- In production since 2014
- Thousands of daily users
- On MODEC FPSO projects since 2016