A lot of people are very familiar with analog and digital data transmission industrial process used in these two words, I do not know what that means. Just literally do not know what they represent what it means. Often it needs to be transmitted on the two data industry, in order to observe the collected data and a device operation state. For a parameter is only two possibilities, if not necessarily the analog switch, and today we took a look at two terms in the end what it meant.
So what is analog? What is a switch?
The amount of analog is a continuously changing, such as temperature, from 0 to 100 degrees, a pressure from 0 to 10Mpa, 1 to 5 m from the liquid level, the valve opening of the motor from 0 to 100%, etc., these amounts are analog.
It indicates that the physical switch has only two states, on and off switching state, the relay is opened and closed, the solenoid valve on and off, etc., or switch the state of energization representatives referred to 0 and 0 1 represents the power off. For example: a button, a switch, relay, an overcurrent relay pressure, belong to this type of contactors, relays, solenoid valve input and output. In other sentence statement saying: switch is a real object, but analog is a virtual object, such as drawing and so on the computer.
Control systems, because the CPU is binary, each bit of data only "0" and "1" states, and therefore, as long as the switch can be represented by the inside of a CPU, for example, "0" indicates open, "1" indicates oFF. The accuracy and the analog is typically required to 8-16 is represented by an analog.
The most common is the analog of 12, i.e. 2-12 accuracy, the highest accuracy of about 4.5 parts per million. Of course, in the actual control system, but also by the accuracy of the analog accuracy limitations of the analog / digital converter and the instrument is generally not possible to reach so high.
Binary input switch including the amount and the opening, is a digital signal, only two states 0 and 1. Binary input from an external device contact protection for a protective device. Out amount of protection provided by the contact to the outside, supplied to the external apparatus, such as a switch tripping off amounts only two opposite operating state, for example, high and low, and de-energize the relay coil, electric shock on and off, PLC may direct input and output switch signal. Some PLC (e.g. Siemens S7 series) will be referred to as a digital switch.
For this continuous analog change physical quantity, such as voltage, temperature, pressure and speed, etc. PLC, can not directly process the analog, input module requires an AD converter with an analog, converts the analog input signal is proportional to digital. Digital (e.g., PID controller output) required by the PLC analog output module DA converter converts them to corresponding digital proportional voltage or current, for external actuator (e.g. control valve or electric drive) use.
These are the analog switch and the meaning of technical grade things count information gateway support 4 digital inputs, 8 analog inputs compatible with a variety of industrial sensor acquisition requirements. In the industrial sector, digital and analog transmission accurately, allowing enterprises in real time, accurate understanding of changes in the operation of the data collection process and equipment, while facilitating remote management, reduce the workload.