What are transmitters?
Transmitters are instruments that capture the process variable and transmit it remotely to an indicating receiver, recorder, controller, or a combination of these.

There are several types of transmission signals:

Pneumatic transmitter
A pneumatic transmitter is a mechanical device that converts mechanical displacement to proportional pressure variations.
These transmitters are based on a nozzle-shutter system, which converts the movement of the measuring element into a pneumatic signal.

pneumatic transmitter

pneumatic transmitter

Pneumatic transmitters generate a linearly variable pneumatic signal of 3-15 psi for the 0-100% measurement range. In countries that use the decimal metric system, the 0.2 – 1 bar signal is also used.

Electronic transmitter
They are generally more accurate and quicker to respond than mechanical ones. This is due in part to the precision of the electronic circuits and in part to the very small movements that are needed in the elastic elements to obtain the electrical change.

Electronic transmitters generate the standard 4-20 mA DC signal at distances of 200 m to 1 km, depending on the type of transmitting instrument. You can still find transmitters that send the signals 1-5 mA DC, 10-50 mA DC, 0.5 mA DC, 1-5 mA DC, 0-20 mA DC, 1-5 V DC, used before normalization to the indicated 4-20 mA dc signal
electronic transmitter transmitters

Digital transmitter
Digital transmitters emit a digital signal consisting of a series of bit-shaped pulses. Each bit consists of two signs, O and 1, and represents the passage (1) or not (O) of a signal through a conductor.

One of the main advantages of this type of transmitter is that its output signal can be received directly by a processor.

digital transmitter

Hydraulic transmitter
The instrument that captures the behavior of fluid and transmits it. These transmitters are occasionally used when high power is required. for this type of transmission there is a great variety since its use is for specific applications there are transmitters with a measurement of 0-2.5 to 0-600 bar in their input signal as for their output signal we have different from 4-20ma, 0- 5 VCD, 1-6vcd, 0-10vcd, 0.5-4.5vcd.

hydraulic transmitter

Telemetric transmitter
in its literal meaning it is a distance measurement.
It is used to remotely monitor and control through a radio signal the start and stop of a pump or pumps in a well, open or close the valve of a tank, know how much water a tank has, monitor the process pressure, its temperature, the electrical variables of the motors/pumps and mainly to attend faults immediately.

It uses frequency hops which means that it has several random transmission channels to avoid external interference and cause poor reception of information. They also transmit in their own encryption code to prevent anyone from causing damage or malfunction in the system.