The Nusonics Model CM-800 Transit-time Ultrasonic Flow Meter can measure highly accurate flow rates in a wide range of fluids. Since the CM-800 utilizes transit time technology, it does not depend on the presence of particles to make an accurate measurement, like a Doppler flow meter. It will operate with high accuracy in a wide range of clean liquids. The flow meter can tolerate up to 2% by volume of particle or bubbles in the process stream without affecting the performance. Primary applications are in HVAC control systems, municipal water systems, oil/fuel oil and clear chemical streams. The CM-800 has a number of advanced features, including:
The ultrasonic flow meter consists of two major elements; the transmitter electronics and a pair of transducers mounted on the pipe. The transmitter portion contains the circuitry which converts the transducer signals to an accurate flow measurement. These electronics are provided in a Nema 4X enclosure or an optional explosion-proof Nema 7 enclosure. The transmitter assembly may also be equipped with a heater/thermostat, which permits operation of the flow meter in cold ambient conditions as low as -60° C (-76° F).
The ultrasonic transducers are provided in four different wetted configurations (HVAC, 1/2″, 1″ and 2″). All wetted transducers are mounted recessed from the pipe wall to avoid obstruction or pressure drop in the flow stream. Transducer pairs are mounted via an integral flange to weld bosses which are aligned on opposite sides of the pipe. The standard material of construction for 1″ and 2″ transducers is CPVC. Economical HVAC transducers, rated to 300 psig, have a removable design and can be easily changed without system shutdown. Optional metal transducers are available for higher temperature and special conditions. Generally, 1/2″ titanium transducers are utilized on pipes up to 6″, 1″ CPVC transducers from 8-24″, and 2″ CPVC transducers for all lines larger than 24″.
Most flow meters are provided with a factory calibrated flow tube with the transducers tested, calibrated and ready for service. Flow tube installation options include ANSI or AWWA flanges, NPT threads, victaulic groove or weld-in-place. As an alternative, Mesa can provide flow meters in a kit form for installation of the transducers onto an existing pipe.
For pipes that do not allow easy welding of flow tube kit bosses, saddle mounted transducer assembly is available. This assembly is very useful for installing the sensor mounting hardware on concrete, cast iron, fiberglass and plastic pipes.
|Range||0.3 to 50 ft/sec|
|Pipe Diameter||2″-200″ (50 mm to 5080 mm|
|Accuracy||+/- 1/2 to 1% of flow reading above 1ft/sec (0.3m/sec)|
|+/- 1 to 2% of flow reading 0.3 to 1 ft/sec (0.9 to 0.3m/sec)|
|Operating Specs Transducers|
|Liquid Temperature||-40 F to 302 F (-40 C to 150 C)|
|Liquid Pressure||CPVC: 250 psig @ 27C|
|Metal: 1000 psig @150 C|
|Sensors||NEMA 7 connection heads standard|
|Sensor Material||1″ & 2″ CPVC; 1/2″, 1″, 2″ titanium, others materials available|
|Cable Length (Max)||1000 ft. (310 m)|
|Analog isolated current output 4-20 mA forward and reverse into 1000 ohm load max. Fault relay, SPST, 130 volt, 0.5A resistive max. 0-5 volt pulse output. RS232 standard/RS485 optional|
|Environment and Power|
|Enclosures||NEMA 4X standard, 10 lb. Optional: NEMA 7 explosion proof, class 1, groups C&D|
|Power||115 or 230 VAC +/- 10%, 50-60 Hz 24VDC optional|
|30 position keypad, 4 x 20 LCD display powered by the transmitter, supplied with 7′ coil cable and connector.|
|All functions for setup and measurement available through RS232/RS485 interface.|