Product Overview

8 AWG PV Wire is the first step up from the residential standard when a solar project needs more current capacity or a longer DC home run. Listed under UL 4703, it provides roughly 50% more ampacity than 10 AWG, enough to handle higher-output string configurations, longer rooftop-to-inverter distances, and the kind of conduit fill situations that push 10 AWG past its comfortable operating range.

It sits at the transition point between residential-class wiring and the heavier conductors used in commercial DC collection. For installers, it is the wire they pull when 10 AWG is not quite enough but 6 AWG would be overkill.

Specifications

Parameter	Specification
Wire Gauge	8 AWG
Conductor	Stranded tinned copper
Voltage Rating	600V/1000V/2000V DC
Insulation	Cross-linked polyethylene
Temperature Rating	90°C wet, 150°C dry
Sunlight Resistance	Sunlight resistant
Ampacity (90°C)	~55A
Jacket	Single-layer XLPE insulation
Listing	UL 4703
NEC Use	PV source circuits, PV output circuits
Color	Black, red, or custom

Core Uses

Higher-Current String Circuits

As panel wattage and string current continue to rise, some residential and commercial string configurations push past the point where 10 AWG provides adequate margin after NEC 690.8 correction. 8 AWG absorbs this increase without requiring a jump to the much heavier 6 AWG conductor.

Extended DC Home Runs

The home run from the rooftop array down to the inverter or main DC disconnect is often the longest single cable path in a residential or small commercial system. When that distance stretches beyond what 10 AWG handles within acceptable voltage drop, 8 AWG provides the lower resistance needed to keep losses in check.

Conduit Fill and Derating Situations

When multiple PV circuits share a conduit, NEC derating factors reduce the allowable ampacity of each conductor. 8 AWG gives installers more headroom in these situations, maintaining code-compliant ampacity even after derating is applied.

Application Scenarios

Larger Residential Systems (10–20 kW)

As residential system sizes grow driven by EV charging, heat pump adoption, and battery storage, string current and total DC output increase accordingly. 8 AWG wire handles the higher current of these larger residential arrays and provides better voltage drop performance on the longer home runs that bigger systems often require.

Commercial Rooftop String Wiring

On commercial rooftops, string current can run higher than residential norms due to different module selection and string sizing. 8 AWG wire serves as the string-level conductor in these systems, providing the ampacity needed for commercial-grade string configurations while remaining manageable for rooftop installation crews.

Ground-Mounted Array Wiring

In ground-mounted systems where the distance from the array to the combiner or inverter pad is significant, 8 AWG wire reduces voltage drop across the run. It is commonly used for string-level and short collection-level circuits in small to medium ground-mounted projects.

Multi-Circuit Conduit Runs

When project design routes multiple PV circuits through shared conduit which is common in commercial buildings with centralized electrical rooms, 8 AWG provides the extra ampacity margin needed to satisfy NEC conduit fill derating requirements without oversizing to 6 AWG.

Selection Guide

Choose 8 AWG PV Wire when 10 AWG falls short on ampacity, voltage drop, or conduit derating margin. Common triggers include:

String current exceeds 30A after NEC 690.8 correction factor
Home run distance creates voltage drop concerns with 10 AWG
Multiple circuits share conduit and derating reduces 10 AWG ampacity below required levels
System design uses higher-output modules with elevated string current

If the circuit demands even more capacity, heavy collection lines, very long distances, or high-current combiner outputs, 6 AWG is the next step up.