TC152
死区：受控系统未采取纠正措施且未使用能量的受控变量范围。另见“零能带”。偏差：设定值与受控变量在任何时刻的值之间的差值。也称为“偏移”。DDC：直接数字控制。另请参见数字和数字控制。数字：一系列开关脉冲，用来传送信息。摩尔斯电码就是一个早期的例子。处理器（计算机）使用数字语言运行。数字控制：一种控制回路，其中基于微处理器的控制器根据传感器输入和设定点参数直接控制设备。编程控制顺序确定设备的输出。降速：由热负荷或冷负荷变化引起的两位控制系统中控制点和设定点之间的持续偏差。增强型比例-积分-微分（EPID）控制：一种控制算法，通过允许设计者输入启动输出值和误差斜坡持续时间以及增益和设定点，增强了标准PID算法。这些附加参数的配置使PID输出在启动时平稳变化到控制点，超调或欠调可以忽略不计。电气控制：一种在线或低压运行的控制电路，使用机械手段，如温度敏感双金属或波纹管，来执行控制功能，如启动开关或定位电位计。控制器信号通常操作或定位电动执行器，或直接或通过继电器切换电气负载。电子控制：一种在低压下工作的控制电路，使用固态元件放大输入信号并执行控制功能，如操作继电器或提供输出信号以定位执行器。控制器通常提供基于固态组件逻辑的固定控制例程。终控制元件：用于改变操纵变量值的装置，如阀门或阻尼器。由致动器定位。狩猎：参见骑自行车。

Deadband: A range of the controlled variable in which no corrective action is taken by the controlled system and no energy is used. See also “zero energy band”. Deviation: The difference between the setpoint and the value of the controlled variable at any moment. Also called “offset”. DDC: Direct Digital Control. See also Digital and Digital control. Digital: A series of on and off pulses arranged to convey information. Morse code is an early example. Processors (computers) operate using digital language. Digital control: A control loop in which a microprocessorbased controller directly controls equipment based on sensor inputs and setpoint parameters. The programmed control sequence determines the output to the equipment. Droop: A sustained deviation between the control point and the setpoint in a two-position control system caused by a change in the heating or cooling load. Enhanced proportional-integral-derivative (EPID) control: A control algorithm that enhances the standard PID algorithm by allowing the designer to enter a startup output value and error ramp duration in addition to the gains and setpoints. These additional parameters are configured so that at startup the PID output varies smoothly to the control point with negligible overshoot or undershoot. Electric control: A control circuit that operates on line or low voltage and uses a mechanical means, such as a temperature-sensitive bimetal or bellows, to perform control functions, such as actuating a switch or positioning a potentiometer. The controller signal usually operates or positions an electric actuator or may switch an electrical load directly or through a relay. Electronic control: A control circuit that operates on low voltage and uses solid-state components to amplify input signals and perform control functions, such as operating a relay or providing an output signal to position an actuator. The controller usually furnishes fixed control routines based on the logic of the solidstate components. Final control element: A device such as a valve or damper that acts to change the value of the manipulated variable. Positioned by an actuator. Hunting: See Cycling.