Terminal layout
| Terminal | Function |
|---|---|
| L1, L2 | Line — incoming power from the breaker panel |
| T1, T2 | Load — outgoing power to the pump or control box |
| Ground screw | Dedicated green screw for the grounding conductor |
230V (double-pole) principle
On a 240-volt system the switch interrupts both hot legs at once — that's what makes it a "double-pole" device: L1 and L2 carry the two incoming hot legs, T1 and T2 carry the two outgoing hot legs to the pump, and both are switched together. Which physical wire lands on which terminal, and how the breaker and cable are rated for your specific pump, is exactly the kind of judgment call a licensed electrician makes on site — it depends on your panel, wire gauge, and local code, not a generic diagram.
115V principle
On a 120-volt pump only one hot leg needs switching, so only L1 and T1 are used; the neutral conductor bypasses the switch entirely. That's the functional difference from a 230V setup — again, the actual conductor landing and neutral handling for your specific panel and wire run should go through a licensed electrician, not a generic guide.
Why the ground terminal matters
The dedicated green ground screw inside the housing exists to give a fault current a safe path back to the panel instead of through a person touching the switch or pump. A missing or loose ground connection is a real shock hazard even when the switch otherwise looks correctly wired — which is one more reason grounding, like the rest of this job, belongs to a licensed electrician rather than a DIY attempt.
After the electrician finishes
Once a licensed electrician has completed the wiring, reinstalled the cover, and restored power, confirm the pump cycles correctly at the expected cut-in and cut-out pressures — see the adjustment guide if the settings need tuning, or the troubleshooting guide if the pump doesn't behave as expected afterward.