WDP420-5NNU Walchem (WDP420-5NNU)
The Walchem WDP420-5NNU controller is now obsolete and the closest equivalent is the WPH620HSSNN-NN controller. The new WPH600 series has upgraded features; for reference, here is the description of the old model:
pH/ORP controller, w/ 2 pulse proportional and 2 on/off control outputs and diagnostic alarm relay, hardwired, cable glands, no 4-20 mA output, no electrode, integrated datalogging and config file import/export via USB flash stick.
Choose the new model on our WPH620HSSNN-NN page or select a model more suited to your needs from the WPH600 series controller or one of the other pH controllers.