Pool pumps are wired to run on either 230V or 115V. Most are run on 230V and are preset at the manufacturers at 230V. If you are going to wire your own pool pump, you must first know what voltage is coming to your pump from the house circuit breaker. Also you must ensure that the electrical supply agrees with the motor's voltage, phase, and cycle and that all electrical wiring conforms to local codes and NEC regulations. If you are unsure of this voltage or are unfamiliar with electrical codes and regulations, have a professional electrician wire your pump for you or at least check your work. Failure to wire the pump correctly can cause electrical shock or can damage your pump motor and void your warranty.
Measure the voltage on the wires going to your pool pump. See "How To Use a Multimeter to Test a Pool Pump Motor - Voltage". This voltage will be either 230-240V or 115-120V. Pool Pump manufacturers commonly list these as 230V or 115V. Generally you will have three wires coming to your pump. For 230V you will generally have a red, a black and a green wire. The red and black wires are both hot. There is no neutral. The green wire is always ground. For 115V the three wires are generally black (hot), white (neutral) and green (ground).
Run conduit from the metal box to the pump. String your three wires thru the conduit and metal elbow into the end of the motor. Screw the conduit collar onto the end of the elbow. Ensure that your wire size is adequate for the HP rating and distance from the power source. Check your pool pump owners manual for the correct size. Wire sizes generally run 14 AWG for motors up to 1 HP and from 14 AWG to 10AWG for larger motors depending on HP and Voltage.
If you are wiring for 230V, the three wires coming to the pool pump from the circuit box are red, black and green. In this example for Hayward pool pumps, red will go to the L1 terminal and black will go to the L2 terminal. The green wire will be under the green screw to the far right. In addition there is a black plug with two wires coming from inside the motor , a black wire and white wire with a black tracer line. The black plug is positioned so that the white arrow on top of the 2 prong black plug is pointing at 230V.
For clarification this picture shows the terminals without the wires. The red wire is attached to terminal 1 of Line 1 (L1). The black wire is attached to terminal 3 of Line 2 (L2). The green wire is attached to Ground (GND). The black plug is positioned so that the black wire is attached to terminal 5. For 230V the white wire is not attached.
If you are wiring for 115V, the three wires to the pool pump will be black, white and green. Attach the white wire to terminal 1 of Line 1 (L1). Attach the black wire to terminal 3 of Line 2 (L2). Attach the green wire under the Ground screw (GND). The black plug is shifted in position so the the black wire is attached to terminal 4 Line 2 (L2) and the white wire is attached to terminal 5. Note: in this position the white arrow on top of the 2 prong black plug is pointing at the 115V label.
Replace the pool pump motor cover and secure it with the two screws.
Lastly your pool pump motor must be bonded in accordance with local electrical code requirements. Use a solid copper conductor, size 8 AWG or larger. Run this wire from from a reinforcing rod to the pressure wire connector provided on the motor housing. Note: In this example the wire coming from the bottom of the picture is going to the pump. The upper wire is going to the heater to bond the heater.