Photovoltaic panel string voltage test table

What is a PV string current test?

For PV string current tests, there are short-circuit and operational current tests. The short-circuit current of a string, Isc is the current that flows when the positive and negative terminals of the string are shorted together, and is the maximum current value of the string.

What happens if you hit a PV module during a test?

Shaking or hitting the PV module during this test may reveal an intermittent or loose connection in the module. This test can more accurately identify complicated module issues than an Open Circuit Test. Please see this video on YouTube as an example:

Can a digital multimeter be used to measure a PV module?

Due to the risk of flying arcs, direct measurement using the current terminal of a digital multimeter (DMM) is not recommended. An AC/DC clamp meter can be used to measure the Isc of the PV module.

What is the operating voltage range of a solar MPPT?

As the string voltages changes, the MPPT will continuously adjust and track the optimum string voltage. The MPPT operating voltage range for most string inverters is between 80V and 600V, depending on the inverter make and model. The voltage range for Solar MPPT charge controllers is generally much lower and varies from 24V up to 250V.