The Walchem WBL310-5N5 controller is now obsolete and has been replaced by the WBL410-5N5U controller which now has integrated USB datalogging and software upgrade capability. Otherwise, both the WBL310-5N5 and the WBL410-5N5U have the same specifications with five powered relays (one blowdown & four feed/alarm), 240 VAC, hardwired, no 4-20 mA output, standard electrode (up to 250 psi).
Please click here to view and/or purchase the new replacement controller and to view literature.