The ornamental design for a powercable accessory, as shown and described.
FIG. 1 is a front perspective view of the power cable accessory according to an embodiment of our design;
FIG. 2 is a front elevation view thereof;
FIG. 3 is a rear elevation view thereof;
FIG. 4 is a right side elevation view thereof;
FIG. 5 is a left side elevation view thereof;
FIG. 6 is a top plan view thereof;
FIG. 7 is a bottom plan view thereof; and,
FIG. 8 is a rear perspective view thereof.
The pairs of closely adjacent, spaced wavy dash-dot broken lines represent a symbolic break in the length and form no part of the claimed design. The appearance of any portion of the article between the dash-dot lines forms no part of the claimed design. The dash-dash broken lines are directed to portions that form no part of the claimed design.