The MonoDrive constant pressure controller for single-phase pumps from Franklin Electric allows users to convert a single-phase conventional pump system to a constant pressure system with a replacement of a three-wire control box. It is designed for use in residential applications with a Franklin Electric 3⁄4 HP or 1 HP, single-phase, three-wire pump that already is in place. Installation is intended to be easy - remove the three-wire control box and install the MonoDrive. Franklin Electric, Card No. 178