www.thedriller.com/articles/86525-constant-pressure-controller-for-single-phase-pumps
Constant Pressure Controller for Single-phase Pumps
September 1, 2004
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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