We claim the ornamental design for a powered appliance support strap, as shown and described.
FIG. 1 is a front perspective view of a powered appliance support strap connected to an example shoulder strap;
FIG. 2 is a front perspective view of the powered appliance support strap of FIG. 1;
FIG. 3 is a rear perspective view of the powered appliance support strap of FIG. 1;
FIG. 4 is a front view thereof;
FIG. 5 is a rear view thereof;
FIG. 6 is a left side view thereof;
FIG. 7 is a right side view thereof;
FIG. 8 is a top view thereof; and,
FIG. 9 is a bottom view thereof.
The broken lines represent portions of the structure that forms no part of the claim. The broken lines in the drawings comprise contour lines and form no part of the claimed design.