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Are you paralleling with the mains?

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Demand for electricity is increasing year on year – it is a global problem, not just related to the UK. Everyone expects to be able to have electricity as and when they need it, however, with increasing demand putting pressure on grid resources, it is inevitable that the existing supply networks will struggle to continue to meet requirements.

With this in mind, the number of independent energy producing applications that are looking at the grid/mains supply, is growing on a daily basis. These applications are primarily required to generate power for their own use when the mains supply fails, but an increasing number are choosing to supply surplus power back to the grid as a way of off-setting investment costs and to support growingenergy consumption demands. However, this can leave the private energy producers exposed to ‘islanding’ if a grid failure occurs down the line without their knowledge, effectively turning the private energy supplier into a ‘mini power station’ and potentially supplying electricity to other connected loads in the area.


Any device that is connected or responsible for exporting power to the grid should have protections and a sophisticated level of monitoring that includes the ability to automatically disconnect in the event of a grid fault, to prevent ‘islanding’. Many renewable energy assets are fitted with inverters that will disconnect the device, but this does not offer a sophisticated level of protection that most energy investors are looking for today.

Deep Sea Electronics plc have released a new, highly sophisticated but user-friendly product to protect energy assets. The DSEP100 Mains Decoupling Relay is designed to protect a wide range of devices generating power in parallel with the mains supply. These include diesel generators, solar (photovoltaic) panels, wind turbines and other renewable energy assets.

The DSEP100 works by reliably detecting mains/grid failures and disconnecting the appliance from the mains supply in line with common international requirements, eliminating the possibility of damage to the embedded generating device. The engineering framework dictates the limits/ parameters for under & over voltage, under & over frequency, vector-shift and ROCOF for over 16A/phase parallel connection. The benefit of using a separate G59/3 (DSEP100) relay, even where inverters are fitted, is to provide this higher level of protection.

Designed to assist with integration with a number of world standards including G59/3, G83/3, C10/11 & CEO10-21. The DSEP100 has many built-in sophisticated

features including:

◗ 2-stage under and over voltage protection

◗ 10 second rolling average over voltage


◗ 2-stage under and over frequency protection

◗ Vector shift protection

◗ R.O.C.O.F. protection

◗ Lockable security tab to prevent configuration changes after commissioning

◗ Zero Sequence Voltage (Neutral VoltageDisplacement) Protection to protect against Earth Leakage from mains

The DSEP100 is perfect for a wide array of paralleling applications such as: Peak Lopping; Fixed Export; Short Term Operating Reserve; No Break, Seamless or Closed Transition; Commercial and Domestic Local Power Generation. For further information, please visit the DSE.


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