EDS · Dual mode sewer flowmeter
E-Flow 3
Contactless radar measures velocity and depth in normal flow. When the sewer surcharges, ultrasonic and sealed pressure sensors take over, with no gap in the record.
E-Flow 3 is an area velocity flowmeter built for harsh, demanding sewer environments. Four sensors share one body at the pipe obvert. In normal flow a pair of contactless radars measures velocity and depth from above the water, so there is nothing in the flow for grease, rag and silt to foul.
When the sewer surcharges and the free surface is lost, a dual 1 MHz ultrasonic Doppler velocity sensor and a sealed 316 stainless steel pressure transducer take over seamlessly. One sensor body, one record, from dry weather flow through to full surcharge.
Peak wet weather flow, overflow volumes and surcharge duration drive inflow and infiltration programs, capacity assessments and regulatory reporting. They are also exactly when a conventional wetted sensor is most likely to be fouled. E-Flow 3 keeps measuring through the whole event.
Specifications
E-Flow 3 in detail.
Velocity
| Method | Contactless 24 GHz radar in normal flow, dual 1 MHz contact ultrasonic in surcharge |
|---|---|
| Range | 0.05 to 20 m/s, recommended above 0.2 m/s |
| Accuracy | Ultrasonic 1 % of reading ± 0.005 m/s; radar 2 % of reading ± 0.01 m/s |
| Resolution | 0.001 m/s |
| Dead zone | Ultrasonic unidirectional 0 to 0.002 m/s, bidirectional ± 0.03 m/s; radar ± 0.05 m/s |
| Velocity radar | 24 GHz continuous wave Doppler, 24° × 12° antenna |
| Ultrasonic | Dual 1 MHz Doppler, 5° beam |
Depth
| Method | 120 GHz FMCW radar in normal flow, sealed pressure transducer in surcharge |
|---|---|
| Range | 0 to 10 m |
| Accuracy | 0.2 % of full scale ± 0.001 m |
| Resolution | 0.001 m |
| Depth radar | 120 GHz FMCW, 14° × 10° antenna |
| Pressure transducer | 316 stainless steel, sealed, with dynamic pressure compensation |
Electrical and communications
| Supply | 8 to 15 VDC, 12 VDC nominal |
|---|---|
| Current | 150 mA at 12 VDC |
| Interface | RS485, two wire |
| Protocol | Modbus RTU slave, register map supplied |
| Response time | 10 s, with configurable damping |
| Firmware | Remote update over RS485 with an EDS logger |
| Configuration | EMS-Flow, from the surface through an EDS logger |
Mechanical and environmental
| Housing | Alloy and engineering plastic composite |
|---|---|
| Sealing | Electronics fully potted, unaffected by temperature cycling |
| Cable | Integral, length to suit the maintenance hole |
| Mounting | Pipe obvert on an EDS bracket, sensor face upstream |
| Water temperature | 0 to 60 °C, accurate to 0.5 °C |
| Service | Sewage, trade waste and combined flows, permanent or temporary |
Ordering
| E-Flow 3 U | Unidirectional. Ultrasonic mode reports absolute velocity. |
|---|---|
| E-Flow 3 B | Bidirectional. Signed velocity and flow; identifies reverse flow and backing up. |
| Bracket | Obvert mounting bracket, sized to the pipe diameter |
| Cable | Integral, length specified at order |
Accuracy is stated under reference conditions. Radar velocity needs a free surface with enough texture to return a signal; below 0.2 m/s the sensor prefers ultrasonic velocity where it is available. Specifications may change without notice. Full details are in the E-Flow 3 datasheet.
Put E-Flow 3 in your network.
Tell us the pipe size, the depth and what you need from the data. We will size the bracket and cable, recommend the logger and telemetry, and can install and commission for you.