FT250 4DEMF MK2
The FT250 MK2 is a second generation subsea four dimensional electric and magnetic field measurement tool. The system collects data to allow three dimensional profiles of magnetic fields and induced voltages within the water column over time. The main use for this tool is for studying the magnetic and electrical fields emitted by subsea power cables to investigate their effects on marine life. It can also be used to monitor power load within a cable remotely and locate burried power cables.
The system has various deployment options the most common being a seabed towed sled (supplied as part of the system) and can either collect the data internally for download later (by WiFi on deck after recovery) or send it in real time to a surface vessel or buoy for onward transmission and processing.
The system works on ultra-low power technology ensuring that the sound to noise ratio is very low enabling the system to record down to ≤10pTrms/√Hz at 1Hz and ±5mV respectively. With up to four 3D magnetometers fitted it allows the system to be used as a gradiometer as well as providing magnetic readings.
- Water depth measured to ±0.1m
- Water temperature measured to ±0.01°C
- Vehicle inclination to ±1° in X and Y axis
- Vehicle acceleration to ±0.1g in X, Y and Z axis
- Noise levels down to ≤10pTrms/√Hz at 1Hz
- Frequency response from DC to 3kHz (-3dB)
- Measuring range from ±70µT to ±1000µT dependent on target
- High resolution internal logging or real time connection to the surface control system
- Rated for use in up to 6000m water depth
- Stability (potential drift at constant temperature and environment) +/- 1mV (24 Hrs) @ 5μA load
- Accuracy (Vs SCE in 3% NaCl @20°C) ±5mV
- Temperature coefficient of -0.65V/ °C
- Operating temperature range -5°C to 70°C
Submarine Cable Signature
This system measures the electrical and magnetic signatures of submarine cables.
As well as measuring the magnetic and eletrical signature of the cable the system can also be used to locate a cable and estimate burial depth.
There are lots of options for the deployment of this system, the normal way is to use the itegrated sled, it can also be used on a seabed frame.