ABB DB021BE是一种模拟量输入模块，它是分布式控制系统的一部分。这种模块适应市场需求，具有可靠性高和抗干扰能力强的特点。

它是一种模拟量输入模块，也就是A/D模块，能将现场由传感器检测而产生的连续的模拟量信号转换成PLC的CPU可以接收的数字量。这种转换一般多为12位二进制数，数字量位数越多的模块，分辨率就越高。

It is an analog input module that is part of a distributed control system. This module adapts to market demand and has the characteristics of high reliability and strong anti-interference ability.

It is an analog input module, also known as the A/D module, which can convert continuous analog signals generated by sensors on site into digital quantities that can be received by the CPU of the PLC. This type of conversion is usually a 12 bit binary number, and the higher the number of digits, the higher the resolution of the module.