When the user presses “Measure Now” on the PVA software running on the computer, a load inside the I-V Measurement Unit is connected to the PV source for approximately 1/3 of a second to gather I-V data. At the end of this time the load is disconnected. It takes approximately 3 seconds for a new I-V trace to appear on screen. Since the load is disconnected before that time, the user can disconnect PV source circuitry after the completion of an I-V measurement without drawing an arc. The PVA can be on or off, but as long as it is not actively measuring at the time (user controls this timing) it will not arc.