The Essex Engineering Model 2407 Alternator is a unit that provides for the on-off sequencing of various devices such as pumps, blowers, etc.

The unit is extremely flexible with all of the set up parameters being customer settable via plug jumpers and/or switches mounted within the unit.  These include first on/first-off or first-on/last-off selection; sequencing in increasing or decreasing order; unit operation as DUPLEX, TRIPLEX or QUADRAPLEX; operation as alternator, contact in/contact out or level control unit with latch-up mode.  In the level control mode devices such as float switches can be used as inputs and will provide a level control system turning on the outputs in sequence and holding them on WITHOUT the use of external latching relays.  When the STOP level float opens, all outputs will be turned off.

Front panel controls provide the operator with the ability to manually select the alternate mode of operation.  When indexed to INTERVAL, the unit will alternate the sequence of operation when the last level is de-energized.  When indexed to OFF, alternation will not occur, except for use of the manual pushbutton on the instrument face.  When indexed to EXTERNAL, the unit can be alternated by the use of an external device such as a time clock, pushbutton, etc.

The input indicator LED's will light as the various input contacts close allowing exact monitoring of the various levels.  The output indicators will light as each output is required.  If an output device, such as a pump, is indexed OFF and a contact input is provided to the Alternator, the corresponding output LED will flash at a slow rate indicating the unit is inoperative and allowing the sequence to skip this unit.  This feature will provide smooth uninterrupted sequencing of outputs by not having to wait for the next level to activate because a unit is inoperative.

Also included are lead unit outputs to provide relay switching capability for analog signals, or remote indication of lead unit.