Buyer's checklist
Solar Installation Parts & Accessories Checklist
The small, low-cost parts every solar installation needs, from MC4 connectors and PV wire to fuses, code labels, bird mesh and monitors, with what to look for in each.
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Panels, inverters, and batteries get all the attention, but a solar installation also depends on a handful of small, inexpensive parts. Most are easy to forget, hard to find at local hardware stores, and not sold by solar dealers to homeowners. This checklist covers the 19 we see needed most often on residential, RV, shed, and off-grid systems anywhere in the US, with what to look for in each.
Safety first
Solar panels produce dangerous DC voltage whenever light hits them, and DC arcs do not go out on their own. Grid-tied rooftop systems need permits and inspections, and the connection to your home should be made by a licensed electrician. Never unplug MC4 connectors under load. Use the parts below for small off-grid projects, repairs, and maintenance, or hand this list to your installer.
Wiring and connectors
Almost every panel made today uses MC4-style connectors and 10 AWG or 12 AWG PV wire. These small parts get lost, damaged, or come up a few feet short on almost every job.
MC4 connector pairs
Join panel leads to extension cables and make custom-length runs.
What to look for: UL 6703 or TUV listing, 1000 V or 1500 V DC rating, and a match to your wire gauge. Do not mix connector brands in one joint.
Check price on AmazonPV wire / solar extension cables
Carries DC power from the array to the controller, inverter, or combiner.
What to look for: UL 4703 PV wire (not ordinary THHN), copper conductors, 10 AWG for most residential runs, and sunlight and UV resistance.
Check price on AmazonMC4 branch (Y) connectors
Wire panels in parallel without a combiner box on small systems.
What to look for: Rated current that exceeds your combined panel current, and the same connector family as your panels.
Check price on AmazonIn-line MC4 fuse holders
Protect each string when three or more strings run in parallel.
What to look for: A fuse rating sized to the panel datasheet (series fuse rating), DC-rated fuses, and 1000 V DC or higher.
Check price on AmazonProtection and code compliance
These parts are cheap but required by the National Electrical Code (NEC) on most systems. Inspectors look for them, and missing labels are a common reason for a failed inspection.
NEC solar warning labels
Required markings for PV disconnects, rapid shutdown, conduit, and backfed breakers.
What to look for: Reflective, UV-resistant labels that match current NEC 690 and 705 wording, and the rapid shutdown label your inverter requires.
Check price on AmazonDC circuit breakers or disconnect
Lets you safely isolate panels from the charge controller or inverter.
What to look for: Breakers rated for DC (not AC-only) at your system voltage, and a lockable disconnect for service work.
Check price on AmazonPV combiner box
Combines several strings with fuses, a breaker, and surge protection in one weatherproof box.
What to look for: NEMA 3R or NEMA 4X enclosure, the right number of string inputs, and included surge protection.
Check price on AmazonDC surge protection device (SPD)
Helps protect electronics from lightning-induced surges on long DC runs.
What to look for: Type 2 SPD rated for your DC voltage, with a visual status indicator.
Check price on AmazonGrounding lugs and bonding clips
Bond panel frames and racking to ground, as code requires.
What to look for: Tin-plated lay-in lugs or WEEB-style bonding clips listed for use with aluminum frames.
Check price on AmazonMounting, roof, and wire management
Hardware stores rarely stock these, and installers often forget to leave spares. They decide whether a system looks clean and stays watertight.
Stainless steel cable clips
Hold PV wire neatly under panels so it does not sag onto the roof or rub.
What to look for: Stainless steel (not plastic zip ties, which fail in UV), sized for your wire diameter.
Check price on AmazonWaterproof cable entry gland
Brings wire through a roof or RV deck without a leak.
What to look for: UV-rated housing, the right number of holes for your cables, and a compatible sealant.
Check price on AmazonSolar-rated roof sealant
Seals around mounts, flashings, and cable entries.
What to look for: Sealant listed as compatible with your roofing material and rated for high heat and UV.
Check price on AmazonZ-brackets or tilt mounts
Mount small panels on sheds, RVs, and ground frames.
What to look for: Aluminum or stainless hardware, the right size for your panel frame, and a rated wind load.
Check price on AmazonTools for installing and testing
You only need a few tools, but using the wrong ones is the most common cause of a loose or melted connector.
MC4 crimping tool kit
Crimps connector pins properly. Pliers will not make a reliable joint.
What to look for: Dies sized for 10 AWG and 12 AWG, with a ratchet that will not release until the crimp is complete.
Check price on AmazonMC4 disconnect (spanner) tools
Unlocks MC4 connectors without damaging the latches.
What to look for: Usually included with crimp kits. Keep a spare pair in the truck or toolbox.
Check price on AmazonMultimeter with DC clamp meter
Checks open-circuit voltage, string current, and polarity before anything is connected.
What to look for: CAT III 1000 V rating, DC current clamp (not AC-only), and auto-ranging.
Check price on AmazonMaintenance and monitoring
These are the add-ons homeowners most often buy after installation, and most local solar dealers do not sell them.
Solar panel bird and critter guard
Keeps pigeons and squirrels from nesting under panels and chewing wires.
What to look for: Galvanized or PVC-coated mesh with clips that attach to panels without drilling.
Check price on AmazonSolar panel cleaning kit
Removes dust and pollen safely from the ground.
What to look for: Soft-bristle brush with an extension pole, and no abrasive pads or pressure washers, which can void warranties.
Check price on AmazonHome energy monitor
Shows what your panels produce and what your home uses, circuit by circuit.
What to look for: A model that supports solar (net) monitoring, with an app that keeps your history.
Check price on AmazonBuying tips
- Buy listed parts. Look for UL, ETL, or TUV listings in the product details, because inspectors and insurers may ask.
- Match parts to your system voltage and current. Your panel datasheet lists open-circuit voltage and the maximum series fuse rating.
- Buy a few spares of connectors and clips. They are cheap and easy to lose.
- Check seller ratings and reviews, and be wary of unbranded electrical parts with no listing information.
Frequently asked questions
What parts do I need to install solar panels?
Can I mix MC4 connector brands?
What size wire do I need for solar panels?
Are solar warning labels really required?
Can I install my own rooftop solar system?
Keep reading
Product information comes from manufacturer listings and general electrical practice. Always follow the instructions for your specific equipment and your local code.