Q: Your literature shows that the ST-U Universal Temperature Sensor housing is
rated NEMA 3R. How can that be? It comes with a big nasty hole in the top and
only a star bushing to plug it up!
Turn it over so the hole faces down, and
you’ve got a NEMA 3R housing (unless
you’re in a location where the rain falls up).
The hole in the Model ST-U package is
designed to accept a conduit connector, and
as long as the conduit entry is below the
point of any wiring connections within, the
NEMA standard is met. It’s actually a good
idea to have a hole in the bottom side of any
outdoor enclosure to allow condensation to
drain out, so the preferred conduit connector
would not be a gasketed, liquid-tight type. If
you’re not using conduit in an outdoor application,
a strain relief grip or other cable connector
fitting is recommended to keep spiders
and wasps from making a home in the
sensor housing.
The star bushing is for indoor use. It provides
for easy ingress of cable and a moderate
degree of strain relief in areas where
insect invasion is not likely.