Is the source isolated from the measurement circuitry?

Is the source isolated from the measurement circuitry?

Yes, there are no Galvanic connections between the source and measurement circuitry. The sine wave source's circuitry is powered by its own transformer secondary and the control signals are optically coupled from the instrument's microprocessor circuitry. As a result, the source and measurement circuitry can be at different potentials, and ground loops are eliminated.