Dwyer A3005 压力开关/仪表

Dwyer A3005 压力开关/仪表

3合1指示压力计，低限和高限控制

压力表前按钮可调设定点和零值

Photohelic开关/压力计功能作为通用高度可重复的压力组合开关结合精密的压力表采用经过时间考验差压计。Photohelic开关/压力计测量控制空气和兼容气体正压，负压或差压。高/低限控制包括两个光电晶体管驱动，DPDT继电器。易于调整设定值指标控制旋钮位于压力表面上。个人设定死区是一个指针宽度-小于满量程的1％。设定点可以互锁提供可变的死区-适用于控制风扇，风门，等。压力计读数是持续的，不受开关操作影响，即使失去电源。在典型应用中，这些开关/仪表控制在高低压集点之间。当压力变化，达到任一设定点压力，限制光电晶体管的红外光由螺旋驱动遮光器被切断。由此产生的光电晶体管电子信号放大，以驱动其的DPDT随动继电器切换发生。接通和断开之间的死区满刻度为1％或更少-刚好足以保证积极的无颤动操作。塑料外壳保护所有的电子元件。固态和集成电路电子的玻璃环氧树脂印刷电路板和自熄端子板。

Photohelic开关/仪表是用来控制空调系统，洁净室，流体及气动控制系统中的压力，材料处理设备，报警或控制排烟系统，在空气结构控制压力，和显示器的呼吸和血压。

3-in-One Indicating gague, low-limit and high-limit control

set points and zero are easily adjusted on front of gauge

The Photohelic switch/gauge functions as versatile, highly repeatable pressure switches combined with a precise pressure gauge employing the time-proven Magnehelic gauge design. The Photohelic switch/gauge measures and controls positive, negative or differential pressures of air and compatible gases. Two phototransistor actuated, DPDT relays are included for low/high limit control. Easy to adjust setpoint indicators are controlled by knobs located on the gauge face.Individual setpoint deadband is one pointer width - less than 1% of full scale. Setpoints can be interlocked to provide variable deadband - ideal for control of fans, dampers, etc. Gauge reading is continuous and unaffected by switch operation, even during loss of electrical power. In typical applications, these switch/gauges control between high and low pressure set points. When pressure changes, reaching either set point pressure, the infrared light to the limiting phototransistor is cut off by the helix-driven light shutter.The resulting phototransistor signal is electronically amplified to actuate its DPDT slave relay and switching occurs. Dead band between make and break is 1% of full scale or less - just enough to assure positive, chatter-free operation. A plastic housing protects all electronic components. Solid-state and integrated circuit electronics are on glass-epoxy printed circuit boards and self-extinguishing terminal boards.<br><br>

Photohelic switch/gauges are used to control pressures in air conditioning systems, clean rooms, fluidic and pneumatic control systems, materials handling equipment, alarm or control fume exhaust systems, control pressure in air structures, and monitor respiratory and blood pressures.