The Walchem WDB300-1N5 controller is now obsolete and has been replaced by the WDB400-1N5U controller which now has integrated USB datalogging and software upgrade capability. Otherwise, both the WDB300-1N5 and the WDB400-1N5U have the same specifications with four powered relays (two blowdown & two feed/alarm), 120 VAC, prewired, no 4-20 mA output, two standard electrodes (up to 250 psi).
Please click here to view and/or purchase the new replacement controller and to view literature.