TC-IDD321
开/关控制：一种简单的两位控制系统，其中
被控制的设备处于完全打开或完全关闭状态
没有中间操作位置可用。
也称为“两位控制”。
气动控制：在空气中运行的控制电路
并使用机械方式，如
温度敏感双金属或波纹管
控制功能，如启动喷嘴和
挡板或开关继电器。控制器输出
通常操作或定位气动致动器，
尽管继电器和开关通常在电路中。
过程：描述可测量的
可变（例如，回风和室外空气的混合
混合空气控制回路中的气流和传热
冷却盘管中的冷水和热风之间）。
通常与传感分开考虑
元素、控制元素和控制器。
比例带：在比例控制器中，控制
受控变量所通过的点范围
必须通过才能移动终控制元件
其全工作范围。以百分比表示
主传感器量程。常用的等效物有
“节流范围”和“调节范围”，通常
以工程单位数量（度）表示
温度）。

On/off control: A simple two-position control system in which the device being controlled is either full on or full off with no intermediate operating positions available. Also called “two-position control”. Pneumatic control: A control circuit that operates on air pressure and uses a mechanical means, such as a temperature-sensitive bimetal or bellows, to perform control functions, such as actuating a nozzle and flapper or a switching relay. The controller output usually operates or positions a pneumatic actuator, although relays and switches are often in the circuit. Process: A general term that describes a change in a measurable variable (e.g., the mixing of return and outdoor air streams in a mixed-air control loop and heat transfer between cold water and hot air in a cooling coil). Usually considered separately from the sensing element, control element, and controller. Proportional band: In a proportional controller, the control point range through which the controlled variable must pass to move the final control element through its full operating range. Expressed in percent of primary sensor span. Commonly used equivalents are “throttling range” and “modulating range”, usually expressed in a quantity of engineering units (degrees of temperature).