Now that we know our minimum storage volume as well as the size of our wet well, we can determine the system’s control elevations. In a duplex pumping system, there are 5 primary elevations of concern: the pump inlet, pumps “off”, lead pump “on”, lag pump “on”, and high water alarm. The distances between these elevations are represented with the following variables: H(x) = Pump Inlet to the Pumps “Off” Elevation H(min) = Pumps “Off” to the Lead Pump “On” Elevation H(lag) = Lead Pump “On” to the Lag Pump “On” Elevation H(res) = Lag Pump “On” to the …
