The Essex Engineering Model 2411 Duplex Pump Controller is designed specifically for controlling the filling and emptying of tanks or basins by means of two pumps.  It accepts standard input signal levels of 1-5VDC, 4-20 mADC and special ranges from a continuous level or pressure transmitter.

The incoming analog process signal is displayed on the front of the instrument via a 3-1/2 digit LED readout.  This same display is also used to set the various turn-on and turn-off points for the control and alarm functions.

Two outputs are available to activate remote relays.  Each has an independent turn-on/turn off setting of 0 to 100% of full scale.  A unit indicator lamp is illuminated when its output is energized.  Turn-on and turn-off points are set by means of their associated 25-turn potentiometers on the face of the instrument.  Each point is set via the read and select pushbuttons which will illuminate a red bar adjacent to the potentiometers being calibrated.  The lean unit is indicated via green LED's which are adjacent to the 1 Lead - 2 Lead selector switch.  The switch provides manual override of the alternation cycle.

Fill/empty action is field selectable for each control point via slide switches within the unit.  Three alarms, two of which have an LED indicator, are provided.  These are high and low level with the signal loss causing the low level LED to flash when activated.   The 2411 Controller may be field programmed, via internal DIP switches, to de-energize the control outputs when any alarm condition occurs.  External inputs are available to deactivate the control and/or alarms or provide alternation via a push button or time clock contact.

Standard with the unit is a time delay, field adjustable from 0.2 to 60 seconds, to inhibit control and alarm action on power up.  This allows system parameters to stabilize before the controller initiates a response.  Optional time delay boards are also available to provide various timing functions.