The Walchem WPH320-142 controller is now obsolete and has been replaced by the WPH420-142U controller which now has integrated USB datalogging and software upgrade capability. Otherwise, both the WPH320-142 and the WPH420-142U have the same specifications with proportional control outputs, 120 VAC, pre-wired with 6” pigtails (wph410) or with 10’ cables (wph420), single isolated analog (4-20 mA) output, submersion flat ph electrode w/preamp (wel-phf-21).
Please click here to view and/or purchase the new replacement controller and to view literature.