A device for controlling an electric field at a high voltage component comprising: - an inner deflector electrically connected to a live high voltage part of the high voltage component; - a resistive layer having a nonlinear current-voltage characteristics adapted for electric field controlling purposes, and arranged along said high voltage component, and which at one position is connected to the inner deflector and at one end electrically connected to a grounded part of the high voltage component; - an insulating layer arranged on said resistive layer and extending at least from said one position towards said one end of the resistive layer while ending without reaching said one end of the resistive layer ; and - a semi-conducting or conducting layer arranged on the insulating layer and extending at least from said one position towards said one end of the resistive layer and past the end of the insulating layer , thereby defining an outer triple point at the intersection of the resistive layer , the insulating layer , and the semi- conducting or conducting layer characterized in that - the resistive layer has first, second, and third adjacent sections as seen from said one position towards said one end, wherein - a portion of the first section extends below said inner deflector and is in contact with, and extend above, the inner deflector , and is located at an end of the inner deflector , - the second section has, in a part thereof, a gradually increasing thickness in the direction towards the outer triple point , and - the third section is extending from the outer triple point to an end of the resistive field grading layer . - an inner deflector electrically connected to a live high voltage part of the high voltage component; - a resistive layer having a nonlinear current-voltage characteristics adapted for electric field controlling purposes, and arranged along said high voltage component, and which at one position is connected to the inner deflector and at one end electrically connected to a grounded part of the high voltage component; - an insulating layer arranged on said resistive layer and extending at least from said one position towards said one end of the resistive layer while ending without reaching said one end of the resistive layer ; and - a semi-conducting or conducting layer arranged on the insulating layer and extending at least from said one position towards said one end of the resistive layer and past the end of the insulating layer , thereby defining an outer triple point at the intersection of the resistive layer , the insulating layer , and the semi- conducting or conducting layer - the resistive layer has first, second, and third adjacent sections as seen from said one position towards said one end, wherein - a portion of the first section extends below said inner deflector and is in contact with, and extend above, the inner deflector , and is located at an end of the inner deflector , - the second section has, in a part thereof, a gradually increasing thickness in the direction towards the outer triple point , and - the third section is extending from the outer triple point to an end of the resistive field grading layer . <EOS>