Monitoring Seals for Water Penetration in Deep-Sea Engineering Using Liquid Level Sensing

In the oil and gas industry, semi-autonomous, remote-controlled underwater robots are used to construct, operate and dismantle facilities at depths of 2000 meters.

There must be a reliable way for liquid level detection and observing the seals in its deep-sea switch cabinet.

What would be the best suggestion?

Optical fiber liquid-level sensors seem to be the best solution for this matter.

Where are these sensors mounted?

Optical fibers for liquid-level sensing have been mounted vertically into a submarine electrical cabinet, where they respond when water reaches a depth of 3mm. This provides detailed indications of any potential seal failures.

How do they work?

There is a millimeter-sized sensing head at the end of the optical fiber. With the sensor and amplifier taking up separate space, these fibers are ideal for cramped situations. Their optical components are sealed against seawater marine atmospheres (protection class IP 68).

To protect the underwater switch cabinet, the customer installs three fiber optic sensors on the ground and attaches them to three amplifiers. These amplifiers emit, amplify and receive light signals. If the beams are interrupted, they will start signals or turn on the connected pump.

These sensors can also observe the inside of the PLC box. In the case of water penetration, other PLCs can take over its function in the network.