The Walchem WCT400-54NN controller is now obsolete and has been replaced by the WCT400-54NU controller which now has integrated USB datalogging and software upgrade capability. Otherwise, both the WCT400-54NN and the WCT400-54NU have the same specifications with bleed & feed, hardwired, cable glands, isolated 4-20 mA output, no electrode.
Please click here to view and/or purchase the new replacement controller and to view literature.