Last updated: March 2026
Your solar panel’s model number is the key to finding its datasheet, confirming specifications, checking warranty status, and sourcing replacement panels. But finding it isn’t always obvious — labels fade, panels are mounted with the back inaccessible, and the same panel can have multiple model designations across markets. This guide shows you exactly how and where to find it.
Where Is the Model Number on a Solar Panel?
Every solar panel has a manufacturer’s label on the back surface, typically in the lower third. The label contains:
- Model number / Part number — the full designation, e.g., “Sharp ND-224UC1” or “Suntech STP250S-20/Wd”
- Serial number — unique to that individual panel (needed for warranty claims)
- Electrical specifications — Pmax, Voc, Vmp, Isc, Imp printed directly on the label
- Certifications — UL, IEC logos
- Manufacturer name and country of origin
How to Access the Back of Installed Panels
From the Roof
For a typical flush-roof installation, the label is visible by looking under the bottom edge of the panel — usually accessible from the gutter line with a ladder. Most residential installations have enough clearance between the panel back and roof surface to read the label with a flashlight. Take a photo for easy reference.
From Your Installer Documentation
Your original installation contract or permit documents should specify the panel model. The utility interconnection application also lists the panel model and wattage. Check these before getting on a roof.
From Your Monitoring System
Systems with per-panel monitoring (Enphase Enlighten, SolarEdge monitoring) show the panel model in the system configuration. Log into your monitoring portal and check the “System Details” or “Equipment” section.
From Your Inverter
Some inverters store the connected panel model in their configuration. Check the inverter settings menu or the installer’s commissioning report.
Decoding Solar Panel Model Numbers
Manufacturer model number conventions vary but follow recognisable patterns:
Sharp Naming Convention
- NU = monocrystalline; ND = polycrystalline
- Number = wattage (e.g., NU-235 = 235W monocrystalline)
- Suffix = production variant (F1, UC1, etc.)
Suntech Naming Convention
- STP = standard polycrystalline module
- Number = wattage (STP250 = 250W)
- Suffix after dash = variant code (20/Wd, 24/VD etc. indicating cell count configuration)
Sanyo/Panasonic HIT Naming Convention
- HIP = HIT panel
- Number = wattage (HIP-195 = 195W)
- Suffix letters indicate generation and market variant (BA19, BCHE5, NKHE5 etc.)
Canadian Solar Naming Convention
- CS6P = 60-cell standard; CS6K = 60-cell KuPower series
- Number = wattage (CS6P-230P = 230W)
- Final letter = cell type (P = polycrystalline, M = monocrystalline)
What If the Label Is Unreadable?
Panel labels can fade or be damaged by UV exposure, water ingress, or physical damage. Alternatives:
- Measure Voc with a multimeter: The open-circuit voltage at known temperature narrows down the possible models significantly — e.g., ~37V points to a standard 60-cell panel; ~44–50V points to a 72-cell or HIT panel
- Check physical dimensions: Measure the panel carefully — dimensions combined with the brand name (if still visible) often uniquely identify the model
- Contact the manufacturer: Some manufacturers can identify panels from serial number fragments or photos — contact their customer service
- Solar O&M company: A professional O&M technician can often identify panels from visual characteristics and electrical measurements
Frequently Asked Questions
How do I find out what solar panels I have?
The fastest way: check your original installation documentation — the contract, permit, or utility interconnection application lists the panel model. Alternatively, the manufacturer label on the back of any panel shows the model number, serial number, and electrical specifications. For per-panel monitoring systems (Enphase, SolarEdge), log into your monitoring portal and check the equipment details. As a last resort, measure the Voc with a multimeter or contact a solar O&M company for on-site identification.
