it’s called a “module”

Often incorrectly called a solar panel, and once called the Bell Solar Battery, The National Electrical Code (NEC) does not use the term “solar panel” as a defined term. Instead, the NEC consistently uses the term “photovoltaic module” or “module”, which is the technically correct designation.

Here’s how it’s defined, btw using it’s common name ‘solar panel’ is ok too.

NEC Article 100 Definition (2023 NEC)

Module (Photovoltaic):
A complete, environmentally protected unit consisting of solar cells, optics, and other components, exclusive of tracker, designed to generate direct current (DC) power when exposed to sunlight.

A module will have it’s manufacturer’s technical specifications listed on the frame somewhere indicating. For example, an REC Alpha module specifications:

Model: REC470AA Pure-RX

Cell Technology: 88 half-cut bifacial heterojunction (HJT) cells with gapless layout

Power Output (Pmax): 470 W

Module Efficiency: 22.6%

Power Density: 21 W/ft² (226 W/m²)

Temperature Coefficient (Pmax): -0.26%/°C

Open Circuit Voltage (Voc): 65 V

Voltage at Maximum Power (Vmpp): 55 V

Current at Maximum Power (Impp): 8.55 A

Short Circuit Current (Isc): 9.1 A

Dimensions: 75.2 x 40.9 x 1.2 inches (1912 x 1040 x 30 mm)

Weight: 46.3 lbs (21 kg)

Frame: Black anodized aluminum

Front Glass: 3.2 mm solar glass with anti-reflective coating

Junction Box: 4-part, IP68 rated with 4 bypass diodes

Connector: Stäubli MC4

Cable Length: 47.2 inches (1.2 m)

A module also will have Warranty information on the placard:

Product Warranty: 25 years

Performance Warranty: 25 years, guaranteeing at least 92% of the original power output by year 25

Certifications:

• IEC 61215:2016 (Performance)
• IEC 61730 (Safety)
• IEC 62716 (Ammonia Resistance)
• IEC 61701 (Salt Mist Corrosion)
• UL 61730 (Fire Type 2)