The Walchem WPH420-3NNN controller is now obsolete and has been replaced by the WPH420-3NNU controller which now has integrated USB datalogging and software upgrade capability. Otherwise, both the WPH420-3NNN and the WPH420-3NNU have the same specifications with proportional control outputs, 120 VAC, pre-wired wph420 with 10’ cables, with (2) e90495 connectors for ew pumps, no 4-20 mA output, none.
Please click here to view and/or purchase the new replacement controller and to view literature.