SteamDonkey
Member
Hi All,
Currently the operators of a wastewater plant have a cord and plug connected 3 hp, 480V, 3-ph submersible pump that is used to pump down any 1 of their 4 aeration basins. There is a NEMA L16-30 receptacle at each of the 4 basins, all wired to a 20A, 3-pole breaker. The pump motor requires separate overload protection but does not have it.
To correct the installation it has been proposed that a fused combination motor starter be installed between the 20A branch breaker and the receptacles to provide overload protection. Also, the existing receptacles would be replaced with horsepower rated receptacles and matching plug. Is this permitted per NEC? My concern is that even though there's only one motor, there are 4 receptacles and the installation might have to meet requirements for multiple motors served by one controller. Does anyone have experience with similar situations? Thanks.
Currently the operators of a wastewater plant have a cord and plug connected 3 hp, 480V, 3-ph submersible pump that is used to pump down any 1 of their 4 aeration basins. There is a NEMA L16-30 receptacle at each of the 4 basins, all wired to a 20A, 3-pole breaker. The pump motor requires separate overload protection but does not have it.
To correct the installation it has been proposed that a fused combination motor starter be installed between the 20A branch breaker and the receptacles to provide overload protection. Also, the existing receptacles would be replaced with horsepower rated receptacles and matching plug. Is this permitted per NEC? My concern is that even though there's only one motor, there are 4 receptacles and the installation might have to meet requirements for multiple motors served by one controller. Does anyone have experience with similar situations? Thanks.