Received an Error Message: R662 Short Circuit Current and Microinverter

Error Message Received:

Typical Causation:

This error is caused by the short circuit current (Isc) of your PV module, when adjusted for the site's average high temperature, exceeds the maximum input current allowed by the microinverter. This then makes the module Isc too large for the microinverter to handle. 

The calculation for this section is the solar module's short circuit current at standard test conditions (ISC) multiplied by 1.25 (NEC Article 690.8). If the dropdown input for "is the solar module bifacial was answered "yes", there is an additional multiplier of 1.3. Therefore, the equation(s) look like this:

ISC x 1.25 = non-bifacial solar modules

ISC x 1.25 x 1.3 = bifacial solar modules

If the final value is larger than the Maximum input (Isc) of the microinverter then this error will be flagged. 

An Example:

The following example is with a Duracell microinverter with a bifacial module with a high Isc. 

Explanation:

After the high temperature correction calculation and the bifacial multiplier calculation the adjusted module Isc is 22.67 amps which is greater than the maximum Isc of the microinverter that has a value of 15 amps. 

Calculation: 13.95A x 1.25 x 1.30= 22.67A

Potential Solution:

As a solution, a non-bifacial module can be used to avoid the 1.30 bifacial multiplier to have a lower module Isc. Another solution is to use a different microinverter with a higher maximum input short circuit current.