Wago's 4-channel digital relay output module features compact 12 mm housing, the 750-515 reduces the cost per channel while maximizing space in the control cabinet. As a component of the fieldbus ...

In terms of programming we should understand the relay is controlled by the ESP-01 module thru port GPIO0. The relay is activated using an active-low signal i.e. a logic-low (L) signal wakes the relay ...