Definition
An electrical relay used in multi-generator aircraft electrical systems that automatically connects two or more generators to the same bus when their output voltages are matched, allowing them to share the electrical load. It opens the connection if a generator's output drifts out of tolerance, isolating the faulty unit from the parallel circuit.
Plain English
A switch that links two generators together so they can power the aircraft as a team, and unhooks one if it stops pulling its weight.
Context Anchor
Seen in aircraft electrical power system descriptions, especially during maintenance or troubleshooting of generator load sharing.
Derivation
From 'parallel' (Latin parallelus, 'side by side') and 'relay' (an electrically operated switch). The name describes its job: switching generators into a side-by-side electrical arrangement so they share the load.
Why Pilots Care
It keeps electrical power balanced across generators, avoiding overload on one unit or loss of redundancy in flight.
Analogy
It is like a coordinator that lets two people carry the same heavy box together. Without coordination, one person may end up carrying most of the weight.
Intuition Check
Do not read “paralleling” as just two wires running side by side. Here it means generators are connected to the same electrical system so they can share the electrical load.
Example Sentence 1
After the right generator dropped offline, the technician checked the paralleling relay to see if it had opened correctly during the voltage mismatch.
Example Sentence 2
During troubleshooting the technician verified the paralleling relay allowed proper load sharing between the left and right generators.