The Walchem WDP420-5N1N controller is now obsolete and has been replaced by the WDP420-5N1U controller which now has integrated USB datalogging and software upgrade capability. Otherwise, both the WDP420-5N1N and the WDP420-5N1U have the same specifications with w/ 2 pulse proportional and 2 on/off control outputs and diagnostic alarm relay, hardwired, cable glands, no 4-20 mA output, two preamplifiers (190783) w/10 ft. cables, prewired.
Please click here to view and/or purchase the new replacement controller and to view literature.