The ornamental design for a connector for powercable, substantially as shown and described.
FIG. 1 is a front view of a connector for power cable embodying our new design, a top view and a bottom view thereof being identical images, a back view thereof being a mirror image;
FIG. 2 is a right side view thereof; and,
FIG. 3 is a left side view thereof.
The broken line portion of the figure drawings is included to show portions of the article that forms no part of the claimed design.