UL 3700 explained
UL 3700 is UL Solutions' Outline of Investigation for Interactive Plug-in Photovoltaic Equipment and Systems, a certification for complete plug-in solar systems. Some state laws name it directly. Others require a different standard, or use broader wording.
State laws that name UL 3700
Maine's law requires a system "listed or certified in accordance with UL 3700" or a comparable standard from a nationally recognized testing laboratory. Vermont's act requires that a device "complies with UL 3700 for plug-in photovoltaic systems by UL Solutions or an equivalent certification by an equivalent Nationally Recognized Testing Laboratory."
State laws that use different wording
UL 3700 is not universal. Connecticut names UL Standard 1741, along with the National Electrical Code, IEEE 1547, and the state building code. Colorado and New Hampshire use broader "nationally recognized testing laboratory" language rather than naming UL 3700. Virginia requires certification by a nationally recognized testing laboratory "as described in 29 C.F.R. ยง 1910.7." Read each linked statute for the exact requirement.
How to check a UL listing
UL Solutions maintains a public certifications directory. A certified product appears there with a file number and the standard it was evaluated against. A manufacturer's claim that a product "meets" or "is designed to" a standard is not the same as a listing in that directory.