I-V curve tracer

An I-V curve tracer is a portable field instrument that measures the current-voltage characteristic of single PV modules or whole strings. From the curve it gives power, short-circuit current, open-circuit voltage, Imp, Vmp, fill factor, and shunt and series resistance. The shape of the curve helps you identify failures, and the tracer also lets you calculate how much power is being lost. Isolate the string under test before connecting it to the tracer. If you only need Voc and Isc, you do not have to measure irradiance or cell temperature. When choosing a tracer for commissioning, consider throughput, accuracy, resolution and whether it can measure high-efficiency and thin-film modules. Tracers have separate accuracy specifications for current and voltage. These uncertainties should be small compared with the string current and voltage variation the commissioning contract allows. Example instruments include the Solmetric PVA-1000, which works with a wireless reference sensor, and the compact Seaward PV200.

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• sentence 5: support check: partial - The listed characteristics match, but the passages call them important to accuracy and productivity, not specifically for choosing a tracer for commissioning.
• sentence 7: support check: partial - The passages name the PVA-1000 with its wireless SolSensor reference sensor and the compact PV200, but the PV200 is not tied to Seaward.
• sentence 7: review: partial - The passages name the Solmetric PVA-1000 with the SolSensor wireless reference sensor and the very compact PV200, but the quoted text never says Seaward makes the PV200; only the source identifier does. -->