DFS 5.1多普勒流量开关
- 金属或塑料管外部的流量控制
- 5安培DPDT控制继电器
- 可调节的ON / OFF设定点
- 高流量或低流量报警模式
- 可调节的时间延迟
- 继电器状态LED
- 流量LED条形图
DFS 5.1 Doppler Flow Switch
- Flow Control from the Outside of Metal or Plastic Pipes
- 5 amp DPDT Control Relay
- Adjustable ON/OFF Set-Points
- Hi or Lo Flow Alarm Mode
- Adjustable Time Delay
- Relay Status LED
- Flow Rate LED bargraph
带非接触式传感器的流量开关
控制来自管道外部的流量。推荐用于“难处理液体”，包括废水，冷却水，浆液，污泥，化学品，粘性液体和研磨剂。Greyline DFS 5.1非常适用于泵保护或激活流量/无流量报警。
易于校准
DFS 5.1控制继电器可以设置为在0.25到10英尺/秒（0.075到3米/秒）之间的任何流速下打开和关闭。插入两个链接用于单独的ON / OFF设置点，或仅插入一个用于Hi或Lo流量警报的链接。将继电器动作时间延迟设置为0到80秒。
明亮的LED指示灯显示继电器状态，LED条形图显示流量。电子设备采用防水聚碳酸酯壁挂式外壳。
夹紧式超声波传感器安装在金属或塑料管的外侧，无需切割管道或关闭流量。它适用于直径为1/2“（12.5 mm）或更大的管道，安装时间为几分钟。没有活动部件，无需维护。屏蔽传感器电缆长度为20英尺（6米），可以向上延伸到500英尺（152米），带有可选的接线盒。
Flow Switch With Non-Contacting Sensor
Control Flow from outside a pipe. Recommended for “difficult liquids” including wastewater, cooling water, slurries, sludge, chemicals, viscous liquids and abrasives. The Greyline DFS 5.1 is ideal for pump protection or to activate flow/no-flow alarms.
Easy to Calibrate
The DFS 5.1 control relay can be set to turn ON and OFF at any flow rate between 0.25 and 10 ft/sec (0.075 to 3 m/sec). Insert two links for separate ON/OFF set points or just one link for a Hi or Lo flow alarm. Set the relay actuation time delay from 0 to 80 seconds.
A bright LED indicator shows the relay state and a LED bargraph shows the flow rate. Electronics are housed in a watertight polycarbonate wall-mount enclosure.
The clamp-on ultrasonic sensor mounts on the outside of metal or platic pipes without cutting the pipe or shutting down flow. It works on any pipe diameter 1/2″ (12.5 mm) or larger and installs in minutes. There are no moving parts and no maintenance is required. The shielded sensor cable length is 20 ft. (6 m) and can be extended up to 500 ft. (152 m) with an optional Junction Box.
多普勒流量开关规格
范围：本规范涵盖由Greyline Instruments Inc.，Largo，Florida/Long Sault，Ontario制造的非侵入式超声波多普勒流量开关。仪表应提供可调节流速下的流量控制。
A.性能规范
流量开关应使用安装在连续管道材料外部的夹持式超声波传感器进行操作，该管道材料可传导声音，包括：碳钢、不锈钢、球墨铸铁、铜、FRP、PVC、ABS或直径为1/2“至180”（12.5 m m至4.5 m）的水泥内衬管道。
应在含有100微米或更大颗粒或气体且最低浓度为75 ppm的液体上操作。
对于0.25 ft/sec（0.076 m/sec）和10 ft/sec（3 m/sec）之间的流量，控制开/关设定点应可单独调节。
B.传感器（传感元件）
流量传感器应为单头超声波不锈钢外壳。
它应安装在管道外部，不会中断流量。
传感器应能在-40°F至300°F（-40°C至150°C）的温度下连续工作，并能承受10 psi的意外淹没压力。
应包括制造商推荐的耦合剂和不锈钢管夹。
应使用20英尺（6米）的屏蔽同轴电缆对连接到单独的电子外壳上，并将防水封装连接到传感器头上。
应能够将传感器电缆延伸至500 ft（152m），无需调整，且不会降低性能或信号强度。
C.电子/控制器
应安装在壁装式防水防尘NEMA4X（IP 66）聚碳酸酯外壳内，带密封防碎窗。
电源输入为100–240VAC 50-60Hz（±10%），最大2.0W。
应包括一个5安培DPDT控制继电器。
应在高或低报警模式下运行，或单独的开/关设定值可在0.25至10 ft/sec（0.076至3 m/sec）之间单独调节。
控制器应包括一个显示继电器状态的LED指示灯和一个显示流量的LED条形图。
控制器应包括从0到80秒的继电器延时调整。
流量开关电子设备/控制器应在-10°至140°F（-23°至60°C）的温度下工作。
应设计为最大限度地拒绝射频干扰。
D.根据需要插入规范的可选功能
电源输入为12-24伏直流电（±10%），最大3.0瓦。
有50英尺（15米）长的连续屏蔽同轴对传感器电缆。
有100英尺（30米）长的连续屏蔽同轴对传感器电缆。
有一个电缆接线盒和总长度不超过500英尺（152米）的电缆，该电缆应为屏蔽同轴对，并安装在导管中，用于机械保护。
E.制造商
流量开关应为Greyline Instruments Inc.制造的DFS 5.1型多普勒流量开关，并保证一年内不会出现材料和工艺缺陷。
规格如有更改，恕不另行通知。如果您在申请中需要更多信息或建议，请联系Greyline。我们可以提供报价，并向贵公司所在地区的Greyline销售代表咨询。
DOPPLER FLOW SWITCH SPECIFICATIONS
SCOPE: This specification covers a non-intrusive, ultrasonic Doppler-type flow switch as manufactured by Greyline Instruments Inc., Largo, Florida / Long Sault, Ontario. The instrument shall provide for flow control at adjustable flow velocities.
A. PERFORMANCE SPECIFICATIONS
The flow switch shall operate with a clamp-on ultrasonic sensor mounted externally on any contiguous pipe material that conducts sound including: carbon steel, stainless steel, ductile iron, copper, FRP, PVC, ABS, or cement lined pipe from 1/2″ to 180″ (12.5 mm to 4.5 m) diameter.
Shall operate on liquids with entrained particles or gases of 100 microns or larger and minimum concentrations of 75 ppm.
The control ON and OFF set-points shall be independently adjustable for flow rates between 0.25 ft/sec (0.076 m/sec) and 10 ft/sec (3 m/sec).
B. TRANSDUCER (SENSING ELEMENT)
The flow sensor shall be single-head, ultrasonic in a stainless steel housing. It shall be installed on the outside of a pipe without interrupting flow. The sensor shall be capable of continuous operation at temperatures from -40°F to 300°F (-40°C to 150°C), and to withstand accidental submersion pressures to 10 psi.
Manufacturer’s recommended coupling compound and stainless steel pipe clamp shall be included.
Shall connect to separate electronics housing with 20 ft (6m) shielded coaxial cable pair with waterproof, potted bond to the Sensor head.
Shall be capable of extending sensor cable up to 500 ft (152m) without adjustment and with no reduction in performance or signal strength.
C. ELECTRONICS/CONTROLLER
Shall be housed in a wall-mount watertight, dust tight NEMA4X (IP 66) polycarbonate enclosure with a gasketed shatter proof window.
Have a power input of 100–240VAC 50-60Hz (±10%), 2.0 W Max.
Shall include one 5 ampere DPDT control relay.
Shall operate in Hi or Lo alarm mode, or with separate ON/OFF set points individually adjustable between 0.25 and 10 ft/sec (0.076 to 3 m/sec).
The controller shall include an indicator LED to display relay status and a LED bargraph to display flow rate.
The controller shall include relay time delay adjustment from 0 to 80 seconds.
The flow switch electronics/controller shall operate at temperatures from -10° to 140°F (-23° to 60°C).
Shall be designed for maximum RFI rejection.
D. OPTIONAL FEATURES FOR INSERTION IN SPECIFICATION AS REQUIRED
Have a power input of 12-24VDC (±10%), 3.0 W Max.
Have 50 ft (15 m) continuous length shielded coaxial pair sensor cable.
Have 100 ft (30 m) continuous length shielded coaxial pair sensor cable.
Have a Cable Junction Box and up to 500 ft (152 m) total length cable that shall be shielded coaxial pair and installed in conduit for mechanical protection.
E. MANUFACTURER
The flow switch shall be a Model DFS 5.1 Doppler Flow Switch as manufactured by Greyline Instruments Inc., and warranted against defects in materials and workmanship for one year.
Specifications are subject to change without notice. Please contact Greyline if you need more information or for advice in your application. We can provide quotations and refer you to the Greyline sales representative in your area.
流量计运作原理
仪器电子设备测量从发送声音到回声返回所需的时间。根据空气中的声速，可以高精度计算出液体表面与传感器的准确距离（0.25%范围）。
由于声速受空气温度的影响，灰线超声波液位传感器包括一个内置的温度传感器。水平/距离测量在传感器的整个工作温度范围内自动进行温度补偿。
传感器的位置应使其能清楚地“看到”液体表面，远离梯子、管道或其他障碍物。Greyline建议每10英尺深度距离侧壁1英尺（每3米深度300毫米）。来自搅拌器的假回波（在传感器下扫过）、湍流和波可以被仪器过滤和忽略。
Greyline模型的范围从简单的4-20mA液位指示发送器，到复杂的监控、控制和数据记录模型。返回greyline产品了解级别模型详细信息和规格。有关包括超声波在内的各种液位仪表技术的信息，请参阅废水液位测量技术。
测量管外脏污或充气液体的流量
多普勒效应由奥地利物理学家克里斯蒂安·多普勒于1842年提出。我们每天都能听到多普勒的例子：火车经过时的汽笛声改变音调，或者赛车驶过我们的位置时的排气噪音。
多普勒技术只适用于含有固体或气泡的液体来反射其信号。这些是“困难”的液体，可能会损坏常规流量计：泥浆、污泥、废水、磨料、粘性和腐蚀性化学品。由于传感器安装在管道外部，因此没有压降，也没有流动障碍物。
为了获得很好性能，多普勒传感器应安装在远离湍流产生装置（如弯管和三通）的地方，远离速度增加装置（如控制阀和泵）。典型精度为满刻度的±2%。多普勒仪器包括一个夹式超声波传感器、连接电缆和一个电子外壳，可以安装在附近方便的位置（500英尺/152米范围内）。传感器可以本质安全地额定安装在危险的额定位置。
需要非常精确的定时电路，但当传感器可以安装在流量均匀分布的管段上时，1%的精度非常典型。
由于超声波信号必须穿过管道到达接收传感器，因此流体中不得含有大量气泡或固体（小于2%）。否则高频声音会减弱，太弱，无法穿过管道。应用包括饮用水、冷却水、水/乙二醇溶液、液压油、燃油和化学品。
渡越时间传感器通常工作在1-2兆赫的频率。高频设计通常用于较小的管道，低频设计用于直径达数米的大型管道。
水槽和堰是专门设计的渠道形状，以表征水流。常见的类型有矩形堰、V型槽堰、Parshall水槽和Palmer Bowlus水槽。水槽或堰型的选择取决于应用：流速、渠道形状和水的固体含量。请联系Greyline Instruments以获取有关为您的应用选择合适水槽或堰的建议。
灰线明渠流量计可以通过菜单选择校准到水槽或堰。明渠流量计电子设备使用内部公式计算流量（流量=k h n，其中“k”和“n”为常数，“h”为仪器测量的压头）。通过直接输入“k”和“n”常数，可以对不常见或自定义水槽进行校准。Greyline还提供了一个PC软件程序“find k&n”，用于根据水槽或堰流图开发校准常数。
Greyline明渠流量计包括非接触式超声波传感器、连接电缆和电子外壳，可安装在附近方便的位置（500 ft/152 m内）。传感器可以本质安全地额定安装在危险的额定位置。仪器显示、汇总、传输和控制，有些型号包括数据记录/流量报告系统。
在没有水槽或堰的情况下测量明渠流量。面积速度流量计连续测量水位和流速，以计算明渠或管道中的流量。
超声波传感器安装在管道或通道的底部。为了测量水位，传感器发送超声波脉冲，这些脉冲通过水传播并从液体表面反射出来。仪器精确测量回声返回传感器所需的时间。根据水中声速，测量声级精度为±0.25%。
用连续注入水中的超声多普勒信号测量流速。这种高频声音（640kHz）从悬浮在液体中的颗粒或气泡反射回传感器。如果流体在运动，回声以与流速成比例的变化频率返回。利用该技术，仪器测量流速的精度为±2%。
greyline面积流速流量计工作在部分满管和溢流管、矩形、梯形和蛋形通道中。
可选-单独的液位和速度传感器
一个单独的向下看超声波传感器可用于高充气或湍流应用。它通过将超声波脉冲通过空气传输到液体表面来测量液位，精度为±0.25%。在水位传感器的基础上，采用水下多普勒速度传感器对水位进行测量。
HOW IT WORKS
The instrument electronics measure the time it takes from transmitted sound to return of the echo. With reference to the speed of sound in air, the exact distance of the liquid surface from the sensor can be calculated with high accuracy (±0.25% of maximum range).
Since the speed of sound is affected by air temperature, Greyline ultrasonic level sensors include a built-in temperature sensor. Level/distance measurements are automatically temperature compensated throughout the operating temperature range of the sensor.
The sensor should be positioned so that it has a clear “view” of the liquid surface and away from ladders, pipes or other obstructions. Greyline recommends 1 ft. from the sidewall for every 10 ft. depth (300 mm for every 3 m depth). False echoes from agitators (sweeping under the sensor), turbulence and waves can be filtered and disregarded by the instrument.
Greyline models range from simple 4-20mA level indicating transmitters, to sophisticated monitoring, controlling and data logging models. Return to Greyline Products for Level model details and specifications. For information on a wide range of level instrument technologies including ultrasonics, read Wastewater Level Measurement Techniques.
Doppler flow meters measure flow from outside a pipe with a clamp-on sensor. Greyline Doppler meters continuously transmit high frequency sound (640 kHz) that travels through the pipe wall and into the flowing liquid. Sound is reflected back to the sensor from solids or bubbles in the fluid. If the fluid is in motion, the echoes return at an altered frequency proportionate to flow velocity. Doppler flow meters continuously measure this frequency shift to calculate flow.
Measure Flow of dirty or aerated Liquids from Outside a Pipe
The Doppler effect was first documented in 1842 by Christian Doppler, an Austrian physicist. We hear everyday examples of Doppler: the sound of a train whistle changing pitch as it passes by, or the exhaust noise from a race car as it speeds past our location.
The Doppler technique only works on liquids which contain solids or gas bubbles to reflect its signal. These are “difficult” liquids that may damage regular flow meters: slurries, sludge, wastewater, abrasives, viscous and corrosive chemicals. Because the sensor mounts on the outside of the pipe, there is no pressure drop and no obstruction to flow.
For best performance Doppler sensors should be mounted away from turbulence creating devices like pipe elbows and tees, and away from velocity increasing devices like controlling valves and pumps. Typical accuracy is ±2% of full scale. Doppler instruments include a clamp-on ultrasonic sensor, connecting cable and an electronics enclosure which can be mounted at a convenient location nearby (within 500 ft / 152 m). Sensors can be rated intrinsically safe for mounting in hazardous-rated locations.
Very accurate timing circuits are required but 1% accuracy is quite typical when the transducers can be mounted on a pipe section with evenly distributed flow.
Because the ultrasonic signal must cross the pipe to a receiving transducer, the fluid must not contain a significant concentration of bubbles or solids (less than 2%). Otherwise the high frequency sound will be attenuated and too weak to traverse the pipe. Applications include potable water, cooling water, water/glycol solutions, hydraulic oil, fuel oils and chemicals.
Transit Time transducers typically operate in the 1-2 MHz frequencies. Higher frequency designs are normally used in smaller pipes and lower frequencies for large pipes up to several meters in diameter.
Flumes and weirs are specially designed channel shapes that characterize the flow of water. Common types are Rectangular Weirs, V-Notch Weirs, Parshall flumes and Palmer Bowlus flumes. The choice of flume or weir type depends on the application: flow rate, channel shape and solids content of the water. Contact Greyline Instruments for advice on selection of a suitable flume or weir for your application.
Greyline open channel flow meters can be calibrated to any flume or weir by menu selection. The open channel flow meter electronics use an internal formula to calculate flow rate (Flow = K Hn, where ‘K’ and ‘n’ are constants and ‘H’ is Head as measured by the instrument). Calibration to uncommon or custom flumes can be done by direct entry of ‘K’ and ‘n’ constants. Greyline also offers a PC software program “Find K&n” to develop calibration constants from a flume or weir flow chart.
Greyline open channel flow meters include a non-contacting ultrasonic sensor, connecting cable and an electronics enclosure which can be mounted at a convenient location nearby (within 500 ft / 152 m). Sensors can be rated intrinsically safe for mounting in hazardous-rated locations. The instruments display, totalize, transmit and control, and some models include data logging/flow reporting systems.
Measure open channel flow without a flume or weir An Area-Velocity Flow Meter continuously measures both Level and Velocity to calculate flow volume in an open channel or pipe.
The ultrasonic sensor is installed at the bottom of a pipe or channel. To measure water level the sensor transmits ultrasonic pulses that travel through the water and reflect off the liquid surface. The instrument precisely measures the time it takes for echoes to return to the sensor. Based on the speed of sound in water, the level is measured with accuracy of ±0.25%.
Flow velocity is measured with an ultrasonic Doppler signal continuously injected into the water. This high frequency sound (640 KHz) is reflected back to the sensor from particles or bubbles suspended in the liquid. If the fluid is in motion, the echoes return at an altered frequency proportionate to flow velocity. With this technique the instrument measures flow velocity with accuracy of ±2%.
Greyline Area-Velocity Flow Meters work in partially full and surcharged pipes, rectangular, trapezoid and egg-shaped channels.
Optional – Separate Level and Velocity Sensors
A separate down-looking ultrasonic sensor can be used for highly aerated or turbulent flow applications. It measures level by transmitting ultrasonic pulses through the air to the liquid surface with accuracy of ±0.25%. Along with the level sensor, a submerged Doppler velocity sensor is used to measure the water velocity.
