In terms of the radar level-measurement technology, light oil products differ from dark ones in a lower dielectric constant, which is directly proportional to the product reflectance and inversely proportional to the electromagnetic absorption degree. That is, the higher the dielectric constant, the better reflection from the surface and the more stable level measurement; while the lower the dielectric constant, the worse reflection from the surface, the higher signal absorption, and, correspondingly, the less operation stability of the level transmitter.

A low dielectric constant of petrol makes requirements for sensitivity of the radar level transmitter higher. To ensure stable level measurement for light oil products with the same metrological characteristics, the radar level transmitters shall be more sensitive than, for instance, for oil level measurement.

ULM radar level transmitters use special unique technologies and level measuring methods that resolve arising problems and ensure equally stable operation of the level transmitter for both dark and light oil products:

Operating frequency of ULM-11 level transmitters – 94GHz. The higher the radiation frequency, the higher the surface reflection coefficient, the narrower the beam, the larger the signal portion that returns to the level-transmitter antenna, and the higher the physical sensitivity of the level transmitter.
Measuring principle. ULM level transmitters are built on a continuous-radar pattern using proprietary adaptive FMCW technologies, which allows you to perform fine tuning of the received signal and to select the desired signal with a high accuracy, even in conditions of very weak reflection, for further processing.
Spectral analysis. ULM level transmitters use proprietary algorithms of digital signal processing to determine the product level with confidence even in conditions of a very weak reflected signal.

Due to above technical solutions, the ULM level transmitters work with equal reliability and stability for both dark and light oil products, which is proved by many years of operation.

The level measuring system on the tank farm can consist of several different ULM series radar level transmitters joined in a unified system. The ULM-11 and ULM-11A1 radar level transmitters have a fully compatible command system and a unified design, which creates a technical solution as efficient in terms of a price/quality ratio as possible, based on ULM level transmitters.