Ultrasonic Liquid Flow Meter with Thermal Energy/BTU Capability
Features LARGE LCD display, shows the Instantaneous Flow Rate, Total Flow, in user selectable units. One of the first Ultrasonic flow meters with data logger. Both 24 VDC and universal AC power capability
- Medium: Any acoustically conductive fluid with less than 5% air bubbles or solids
- Pipe size: ¼” to 240”
- Flow rate: Supports velocities up to 40 f/s or 12 m/s
- Temperature: - 20 - 110 ℃
- Transducer material: Aluminum and 304 SS
- Cable length: 15’
- Accuracy: ±1% from 0.15 to 40 f/s (0.05 to 12 m/s)
- Resolution: 0.01 ft/s (0.00025 m/s)
- Response time: 150 ms measuring cycle typical
- Transducer Frequency: 1 MHz
- Clamp-on transducers: encapsulated design IP68
- Enclosure Grade: IP65
- Display LCD Screen
- Power Supply: Set up to use either 24VDC or a 86-240 VAC Universal Power Supply. Only one at a time. Consumes 500 mA max
- Output: 4-20mA + 0-10K Hz + Standard ModBus RTU Communication protocol
- Ultrasonic flow meter with data logger
- Note: For 1 to 5 VDC output, add 250 Ohm resistor to 4 to 20 mA loop
NOTE: Menu 90 shows Signal Strength and Menu 00 shows main flow rate and total. Frequently, fine tuning may be had by invoking Menu 90 and making small movements of one of the transducers to get the highest signal. Numbers over 80% are considered very good. Also, set the Filter Coefficient (We could call this the time constant or response time), with Menu 40 to 1 second to make the meter respond quickly. Then, put back to 4 seconds and save with Menu 26 and hit enter twice.
§3.1.6 Validating meter function.
Entering a pipe outer diameter (Menu 11) of zero, results in the display to show the flow velocity: 1.2345678m/s (4.0504ft/s) [use down arrow to view], flow rate= will vary, and display “R”status on Menu 00. Inputing a set value in M44 will change the totalizer output. Use this function to test of the flow meter and network software without having to connect the transducers. If they are connected the flow rate may be + or -
Acoustic Coupling Grease Specifications:
Dow Corning Product Name: MOLYKOTE™ BR-2 Plus High Performance Grease
This material is designed to remain in a gel like form to increase the acoustic coupling of the ultrasonic transducers to the pipe. This material works from -57 to 204 Degrees C which is above the specs of the transducers.
Here is a source to buy it: MSC # 31735293
In a "pinch" one could use KY Jelly from the drug store but it is runny. The goal is to have a material that will not have bubbles in it and provides good sonic coupling. Air bubbles are the "enemy" of ultrasonic transducers. Using traditional Silicone sealant, such as that used for sealing windows, could also be used in an emergency but you MUST assure there are no air bubbles.
MAG Meter Complimentary Product line
Ultrasonic Meter Transducer Installation requirements: On this flow meter, as well as of all flow meters, it is CRITICAL that the pipe remains full at all times. This meter requires that the flow remain relatively consistent. Note 10 diameters clear of obstruction upstream and 5 diameters down.
Simple Overview how Ultrasonic Flow Meters Work
How to make a Batch Controller with an Ultrasonic Flow Meter:
Video showing How to connect 4-20 mA on the Ultrasonic Flow Meter
Simple External Datalogger instructions, showing how this can work on ANY flow meter with a 4-20 mA output. PDF showing Datalogger Instructions here
Clamping system for pipes larger than 10" OD. Install by securing ends with clamps WITHOUT the transmitter and then stretch the nylon coated SS wire over the transmitter. BE SURE to grind a CLEAN area for the transmitter to conduct the sound AND use the Acoustic Coupling Grease on the transmitter/pipe interface.
Note how strap is used.
Important notes on the use of Clamp On Meters of all brands:
While it is compelling to utilize these meters because of their ease of installation it is critical that the pipe material, thickness and ID are well known. Many times older pipes can have significant corrosion reducing the inner diameter to such a level that the sonic energy can not penetrate. Frequently banging on the pipe with a double jack can remedy and remove large "mushroom like" growths it can not remove long term built up scale that tends to absorb energy. Banging on some piping systems is NOT an option because it can break or cause a leak. We can not guarantee that a Clamp On Meter is ideal for the installation if the internal condition of the pipe is unknown. We will be happy to provide consultation to give ideas on how to measure flows in such conditions but can not be held to task should the internals of the pipe not be verifiable. Generally we will not refund the purchase price on a system where the pipe condition is difficult to obtain.