Tripp Lite Basic PDU, 30A, 10 Outlets (C13), 208/240V, L6-30P, 12 ft. Cord, 1U Rack-Mount Power (PDUH30HV) https://www.amazon.com/dp/B010KNVZ0A/ref=cm_sw_r_apan_glt_fabc_M01RZPH6QX9GBH7145SZ?_encoding=UTF8&psc=1
Depending on your (growth) goals and your electric capacity, your electrician can install multiple 30Amp outlets. You'll plug a PDU into the outlet. And you'll plug up to 4 Antminer S9s into the PDU. Here's the PDU, and here's the cords: https://www.amazon.com/gp/product/B010KNVZ0A/ref=oh_aui_detailpage_o03_s01?ie=UTF8&psc=1
https://www.amazon.com/gp/product/B0027JTJ22/ref=oh_aui_detailpage_o03_s00?ie=UTF8&psc=1