www.thedriller.com/articles/84716-pump-controller-for-constant-pressure
Pump Controller for Constant Pressure
February 1, 2006

The CSA-listed Balanced Flow NEMA 3R pump controller from Goulds Pumps now is available in 2- and 3-HP (230V) models. The system is engineered to provide consistent pressure even as system flow requirements vary.
Goulds Pumps, Card No. 228