The Collaborative International Dictionary of English v.0.48:

low-voltage \low-voltage\ adj.
   1. (Electricity) subjected to or capable of operating under
      relative low voltage, usually considered as no greater
      than 250 volts. Contrasted with high-voltage.
      [WordNet 1.5] low-warp loom

WordNet (r) 3.0 (2006):

low-voltage
    adj 1: subjected to or capable of operating under relative low
           voltage [syn: low-tension, low-voltage] [ant: high-
           tension]