Non invasive tank level sensors have been limited to Ultrasonic up til now. Ultrasonic sensors operate at around 100kHz. If under the tank have the signal may be blocked by solids or material in the water. If above the tank, they are susceptible to foam and general interference from reflection. They are just not suitable for Black Water or Grey Water.
Phased Coherent radar operates at 60gHz and penetrates foam with great accuracy. Up until now, Radar has been an expensive choice and used in very high value applications. But the introduction of Phased Coherent Radar to EV's opened the door for inexpensive tank sensor applications.
In pulsed coherent radar, a series of short-duration radio frequency pulses are transmitted towards the water line from above. These pulses are reflected back and received by the radar system's antenna. The received signals are then processed and analyzed to determine the depth.
The term "coherent" refers to the radar system's ability to maintain a constant phase relationship between the transmitted and received signals. This coherence allows for more accurate measurements and improved signal processing techniques, such as coherent integration, which enhances the radar's sensitivity and range resolution.
Pulsed coherent radar systems are commonly used in various applications, including military surveillance, air traffic control, weather monitoring, and automotive radar systems. They offer advantages such as high accuracy, long-range capabilities, and the ability to distinguish multiple targets in close proximity.
Video Showing Phased Coherent Radar raw signal
and corresponding tank level
as sensor is moved above water.
This is the most advanced software development we have developed as there are 3 independent IC's. fresh libraries had to be created.
This wired sensor:
- 10-30V DC input power
- CAN output signal
- 0-5V output for Victron Tank 140 and Simarine
- Bluetooth 5.3 Adv output
- Deadband 30mm
- Max Depth 2000mm
- Repeatability 2.5mm
Safiery declares that this sensor is compliant with the European commission radio equipment directive 2014/53/EU article 3.1 and 3.2.
The base of the Sensor has 2 sets of holes:
- SAE 5 bolt hole
For Plastic Tanks:
- Glue Sensor to top of tank. The SAE bolt holes form the basis for the bonding.
- 2m long cable 6 core
- CAN Hi Lo
- Power in 10-30V+ and Neg
- Vout 0-5V
- Feature In (used for simple calibration)
- Feature in to ground: 0%
- Feature in to Hi: 100%