Our USB Shutter control for simulators is a simple USB cable that terminates in a Sub-D and/or a BNC connector. The output is a TTL signal that most of the solar simulators support.
Most of the modern solar simulators are equipped with a mechanical shutter. The USB Shutter control is used to cover the light when the solar cell is not measured. This prevents the solar cell material from heating up which can be very important as a solar cell has a large temperature dependency. Only during the measurement the shutter should be opened.