Mar 2013
Electricity Transmission
33Kv Voltage Transformer (VT) Shutter Locking Device
Mar 2013
National Grid Electricity System Operator
National Grid TO Innovation Team
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Innovation Funding Incentive
High Voltage Technology
The staged development of Voltage Transformer (VT) shutter locking device to promote safe switching activities.
The development in the short term of an interim solution utilising an approved method to access and apply a locking device to the VT Shutters for safety switching activities. Reduction in the level of exposure to the danger from working at height.

The interim development of a shutter locking device will immediately reduce Maintenance Delivery Electricity (MDE) exposure to the dangers of working at height. But only when the final solution is developed will the dangers of working at height be reduced to zero.

The development in the long term of a final solution where the VT shutter is modified to provide a locking function at ground level for safety switching activities. It is proposed the final solution will enable the lock to be applied from ground level. As a direct consequence it will reduce to zero the requirement to work above ground level.

The final development of a shutter locking device will take a prolonged time to implement due to the outage constraints the HV system places upon MDE. It is envisaged the final solution will take up to 5 years to implement fully and therefore an interim solution will be necessary to minimise MDE’s exposure to the dangers of working at heights.