Quick answer
L14-30P is the plug and L14-30R is the receptacle. Both belong to the same 30A, 125/250V locking family. Confirm the label on each endpoint and do not substitute TT-30 or L5-30 simply because they also carry a 30A rating.
What the L14-30 designation tells you
The L identifies a locking family. The 14 family uses a configuration that supports 125/250V service, while 30 identifies the 30A class. The final P or R identifies plug or receptacle.
Leviton documentation identifies L14-30 as a three-pole, four-wire grounding configuration. Those details must be preserved across the generator outlet, cord, connector, and inlet.
Common generator and inlet applications
Many portable generators provide an L14-30R outlet for higher-capacity loads or a compatible building inlet. A cord may use L14-30P at the generator end and L14-30R at a compatible inlet end.
The presence of the receptacle does not approve a building connection by itself. A house also requires properly installed transfer equipment.
L14-30 is not TT-30 or L5-30
TT-30 is a 125V travel-trailer configuration. L5-30 is a 125V locking family. L14-30 is a 125/250V four-wire locking family.
Adapters between different systems require more than a physical fit. Verify voltage, conductor paths, connected loads, and the adapter’s documented application.
L14-30 matching checklist
Read the generator receptacle, destination inlet, and cord assembly labels. Confirm P and R direction, 30A rating, 125/250V configuration, four-wire grounding, environment rating, and suitable length.
Stop if any label is missing, altered, or inconsistent with the equipment manual.
Frequently asked questions
Common questions
What is the difference between L14-30P and L14-30R?
L14-30P is the plug; L14-30R is the receptacle. They are mating parts of the same connector family.
Is L14-30 a 120V or 240V plug?
The family is rated 125/250V and supports a split-phase configuration. The actual connected equipment and generator setup still determine how it is used.
Can L14-30 connect directly to house wiring?
It may connect to a compatible power inlet, but the building still needs properly installed transfer equipment. Never backfeed a household outlet.
Primary references
CordFind summarizes connector specifications and public safety guidance. Always follow the instructions supplied with your equipment.