SJT:
Are you talking about what I call a 'cowboy' strap? 1/4-20 hdwe on bottom to secure pipe, and a 'available' mounting hole at the top to secure the strap to rod, or structure.
That strap is only listed for pipe support IMHO.
As to supporting a luminaire from a raceway that is used for wiring, that's a 'no-no', unless the raceway is specifically listed for support. (ie: strut assembly, vs EMT)
