TCAs stands for; Traffic alert and Collision Avoidance System. It can be translated as traffic warning and Collision Prevention System in Turkish. The purpose of this system is to show you traffic within a certain region and warn you when necessary. This warning can come in two ways.
1-TCAS WARNING :
It warns you of traffic at a distance of +/- 1600 feet and + / – 7 NM.(Indicated by yellow.) When you receive a TCAS alert, you should inform the ATC if it is active and follow the necessary steps to avoid a possible collision .
It warns you of traffic at a distance of +/- 900 feet and +/- 3 NM.(Indicated by Red) a beep sounds during the TCAS alarm. You can mute this sound by double-clicking on the TCAS text in your EHSI panel. When you receive a TCAS alarm, you must take the necessary steps as soon as possible to avoid a possible collision . Because your time is very limited. You must alert the control immediately . It is very important that you alert control very quickly in areas with heavy traffic . Because you can cause a new problem.
The TCAS computer is in the avionic compartment . The lower TCAs horizontal antenna is located at station 385 on the upper fuselage of the aircraft and the lower TCAS horizontal antenna is located at station 385 on the lower aircraft (antenna placements Boeing 737-600/700/800/900 the example is given by acceptance. It should be noted that as the aircraft type changes, the antenna residential area will change.
The TCAS computer uses the information it receives from other aircraft to calculate whether target aircraft within the TCAs control area pose a collision hazard. In order for the TCAS computer to communicate with other aircraft, these aircraft must also have a TCAS system. Two TCAS computers use shared data for coordinated maneuvering and to avoid possible collisions.
An example that you can see live on a youtube channel on this topic ;