DASI III and DASI IV

Offshore Hydrocarbon Mapping plc (OHM) is a leading provider of remote electromagnetic sensing services designed to detect the presence of offshore oil and gas. Their equipment generates information on the resistive structure of the subsurface. Because hydrocarbon accumulations are generally very resistive, this method can indicate the presence of oil and gas in deep water situations.

At the request of OHM ETA conducted a review of the power distribution system for their existing DASI III system which included the design of an upgrade to the high voltage (HV) system from 1.8 kV to 4.5 kV. ETA then designed and supplied the HV Line Insulation Monitoring (LIM) system for this upgrade.

Building on the success of the DASI III system OHM was constructing a new system, DASI IV. For this project ETA were contracted to supply a variable HV (up to 4.5 kV) power distribution system including control monitoring and protection circuits. This was fitted into a fully lined and air conditioned 20 ft ISO container which was subdivided to provide a storage space at one end.