FOSREM team replaced the previous FOS1 sensor with the new FOS5LL with a 15 km long fiber loop. The old one was working since July 2017 and give us a lot of data. The new FOS5LL (Long Loop) is ten times more accurate, has a long 15000 m fiber optic loop and 1.5 m diameter. It’s working in a closed-loop configuration with 1310nm light.
The FOS-5 sensor contains a complete fibre-optic Sagnac interferometer with 250 mm diameter fiber-optics loop, analog to digital conversion circuits, FPGA based digital processing unit for close-loop operation, power conversion and management parts. All of these are placed in a robust case, meeting the IP67 requirements.
This internal digital processing unit provides rotation speed (Omega) value directly in digital form. The FOS-5 has an RS-485 interface for data and USB interface for diagnostic. The connection provides data transmission and power supply from PCU over only one, standard M12 cable within the distance of 500 meters.