Overview Global Water's FC220 Open Channel Flow Monitor is a reliable and accurate instrument for measuring and totalizing open channel flows for all flumes and weirs, as well as for any gravity-type open-channel flow application. The flow meter measures water depth using any 4-20mA water level sensor's output including Global Water's highly accurate submersible pressure transducer or ultrasonic water level sensor. The flow meter's powerful microprocessor instantly calculates and displays water flow and totalizer values in user-selectable units using one of several water flow calculation modes. The Open Channel Flow Monitors have an 8-button keypad that easily guides the user through the setup menus.
Open Channel Flows For any open channel that is free flowing, there is a specific relationship between depth of water and flow rate. Whenever a given depth occurs, there will always be the same water flow. Therefore, if the flow rate is known for each depth, a depth-to-flow relationship can be constructed. The Open Channel Flow Monitor supports a large number of different types of flow calculation modes. Over 40 pre-programmed flume and weir tables are included with the open channel flow meter. For monitoring in round pipes and open rectangular channels, the Manning's Equation mode allows the user to enter their own parameters for material, slope and pipe or channel dimensions. The open channel flow monitor also allows the user to define standard flow equations, which can calculate flow for almost all flumes and weirs. Another mode lets the user enter parameters for a best fit 3rd order polynomial, which is useful for calculating flow based on empirical data and lookup tables. A 16-character name can be programmed into the FC220 water flow meters by the user to identify the installation site or show other information about the configuration.
Level Measurement Global Water's standard open channel flow monitors can measure flow depth with any 4-20mA water level sensor including the WL400 Water Level Sensor, which is a fully submersible pressure sensor constructed of stainless steel. Submersible pressure transducers should be mounted slightly below the "zero" flow depth of the open channel, upstream from the throat of the flume or weir. For open channels with no primary device, the sensor should be mounted below the lowest expected water depth. Global Water also offers a WL700 ultrasonic water level sensor that allows the Open Channel Flow Monitor to measure semi-solid flows or flows that are not suitable for a standard submersible pressure transducer. Global Water recommends that the ultrasonic sensor option only be used in areas where AC power is available. Because the open channel flow monitor accepts a 4-20mA input signal, it can be mounted up to 3000 feet away from the water level sensor.
Flow Monitor Display The Open Channel Flow Monitor displays water flow with up to 7 digits, allowing for very large flows to be displayed. The totalizer records up to 9 digits of flow volume in non-volatile memory and is password-protected from reset. Available volume units are cubic feet, gallons, million gallons, cubic meters and liters; time units include seconds, minutes, hours and days. This allows the open channel flow meter to display flow in 20 different user-defined units. Water level is calibrated and displayed in feet, inches, meters or centimeters; a water level offset function allows the measured water level to be adjusted to compensate for variations in the sensor installation.
Flow Monitor Output The FC200 Flow Monitor has four independent relay outputs for triggering external devices like water samplers and monitoring devices. The relays can be separately programmed to trigger based on volume per pulse, and threshold settings can be used to limit triggering to flows above preset levels. There is also an accurate and scalable 4-20mA output provided for monitoring the flow using data loggers and PLC devices. The flow monitor offers a programmable power-saving features that allow the supply current to be reduced for remote monitoring applications.
Features:
Easy-to-use interface with user selectable flow tables
Accepts any 4-20mA water level sensor's input
4-20mA output signal for recorders or displays
Relay outputs for alarms, sampling, or datalogging