A threaded, gasketed sealing hub that bolts or threads onto an enclosure entry and is listed for wet locations. It seals the raceway entry on top of outdoor equipment.

Can conduit enter the side or bottom with a raintight connector?

Yes. Below the level of the live parts, raintight connectors are acceptable in wet locations. The wet-location-listed fitting rule applies to entries above live parts.

Do you need a Myers hub on top of an outdoor panel, or can you use a raintight EMT connector?

Q: Can I use a raintight EMT connector on top of an outdoor panel?

Generally no. NEC 312.2 requires fittings listed for wet locations where a raceway enters above uninsulated live parts, and a knockout-and-locknut entry does not meet that.

On top of an outdoor enclosure, use the hub. NEC 2023 312.2 says that in wet locations, where a raceway or cable enters a surface-mounted cabinet above the level of uninsulated live parts, the fitting must be listed for use in wet locations. A Myers style threaded hub, or the manufacturer bolt-on hub kit for a meter-main or loadcenter, carries exactly that listing and seals the entry with a gasket and tapered threads. A standard raintight EMT connector through a knockout with a locknut generally does not carry a wet location listing for that top entry application, which is why inspectors turn them down on panel tops.

Raintight is not the same as wet location listed

Raintight compression connectors are listed to keep rain out of the raceway system when installed in a vertical run, but the knockout entry itself, locknut against sheet metal, is not a sealed connection. Water tracks along the enclosure surface, finds the knockout, and drips straight onto the main lugs below. The hub exists precisely because the top of a live enclosure is the worst possible place for that leak. Below the level of the live parts, on the sides or bottom of the can, raintight connectors and even plain entries with the right fittings are acceptable because a drip lands on the enclosure floor, not the bus.

What passes on top

Three clean options: a factory hub opening with the listed hub kit bolted in, a Myers style hub sized to the raceway thread, or coming into the enclosure from the bottom or the sides and avoiding the top entirely. Bottom entry is the belt and suspenders answer for meter-mains in coastal and high-rain areas, and plenty of utility service manuals require it.

Do not forget the drainage thinking

312.2 also expects the enclosure itself to be placed or equipped to prevent moisture from entering and accumulating, with mounting that leaves at least a quarter inch air space off the wall for surface-mounted cabinets in wet locations. A perfect hub on a panel strapped flat against wet masonry still corrodes off its back wall.

Field notes

Match the hub to the conduit size and use a metal bushing on the inside. If the existing can has only knockouts on top and the raceway must enter there, the honest fix is a hub adapter listed for retrofit knockout use, several manufacturers make gasketed sealing hubs listed for exactly this. Silicone around a locknut is not a listing, and every inspector has seen how that movie ends.