The UX90-004 includes an internal two-axis AC magnetic field sensor that is designed to pick up the presence of an AC field when the logger is attached to the motor housing. In the event that the motor housing is not accessible (with a submersible pump, for example) an external current switch can be used to provide a contact closure to the external input of the logger that represents a motor "ON" state. Note that the current switch must be clamped around only one motor hot lead in order to work correctly.
Attached is a wiring dagram that shows how to connect the UX90-004 Motor On/Off Logger to a motor using the CSV-A8 Current Switch.
UX90-004 & CSV-A8