The ABACUS ELECTRICS IEC optical probes are bi-directional interface devices utilising infra-red light. Connecting to the serial port of a computer or hand-held terminal they permit galvanically isolated communication with utility tariff meters as specified in European Standard IEC 62056-21:2002 (formerly IEC1107:1996).

Probes are available for use with lap-top or desk-top computers, and also for use with a variety of the hand-held computers commonly used for field data collection.

The F9U probe has a USB connection and derives its power from the host computer.