WDP420-1NNN, Walchem pH/ORP Controller (WDP420-1NNN)

The Walchem WDP420-1NNN controller is now obsolete and the closest equivalent is the WPH620PSSNN-NN controller. The new WPH600 series has upgraded features; for reference, here is the description of the old model:

2 pulse proportional relays & 2 on/off dry contact relays & 1 dry contact dedicated alarm, 120 VAC, pre-wired with 20 ft. cables for E Class pumps, no 4-20 mA output, no electrode, no USB

Choose the new model on our WPH620PSSNN-NN page or select a model more suited to your needs from the WPH600 series controller or one of the other pH controllers.