If you’re installing a new swimming pool, you’ll need to run power to the pump. With a lot of different size cables and wires available, you may be unsure of what thickness you need to run for your pool pump.
The National Electrical Code (NEC) states the minimum wire gauge (thickness) for pool pumps is #12 AWG. Pool pumps generally require between a #6 AWG and #12 AWG wire depending on the motor’s horsepower, voltage, and distance from the fuse board.
In addition to choosing a cable suitable for your pump, you also need to choose a cable that will satisfy the codes and regulations in your location. We’ll break down everything that’s involved in choosing the correct size cable for your swimming pool pump here.
Disclaimer: This information is general in nature and should not be relied on. Always consult a qualified electrician and the codes in your area.
Codes and Regulations
The first consideration when choosing the appropriate size cable for your pool pump is to look at any codes and standards for your location.
The National Electrical Code (NEC) or NFPA 70 is an electrical standard that has been adopted by 50 states in the USA. It covers the electrical requirements for swimming pool pumps. Your location likely uses this code or a variation on it.
How Is Wire Thickness Measured?
Electrical cables and wire thicknesses are measured using the American Wire Gauge (AWG) system. This is the standard system for measuring all electrical cables in North America.
The thinner the cable the larger or higher the number with 40 AWG being the thinnest and 0000 AWG being the thickest.
Cables used for pool pumps are usually between #8 and #12 AWG.
What Wire Gauge (Thickness) Do Pumps Need?
Minimum Wire Gauge for Pool Pools
As per the National Electrical Code, the minimum wire thickness (gauge) for a swimming pool pump receptacle is #12 AWG. The cable must be an insulated copper wire which is grounded. It also must be in a conduit.
Distance of Pump to Pool
Cables have resistance in them. And the longer the cable, the higher the resistance will be. This resistance increases the current demand on the circuit. The further the pool pump and pool pump outlet are located from your distribution board, the thicker the cable needs to be.
The thicker an electrical cable is, the more current it is able to handle.
So in other words, if your pump is located a few meters from your electrical board (fuse box), you won’t need an overly thick cable. If on the other hand, it is located 50 feet away, it will require a thicker cable.
Pool pumps come in 115 VAC or 230 VAC. Many use 230 VAC. The voltage your pool pump operates at affects the thickness of the wire you’ll need.
It comes back to how much current your pump draws. The more current your pump draws, the thicker the cable you’ll need. You can think of pool pump current requirements as water running through a pipe. A small water pipe allows a small amount of water to flow, just like a thinner cable will allow a small amount of current. A bigger water pipe allows more water to flow, and a thicker cable allows great current to flow.
Coming back to the pump voltage. A 1-horsepower 115 V pool pump draws twice the current of its 230 V equivalent. Even though they’re both rated at 1 hp, the 115 V pump will require a thicker cable to accommodate the extra current.
This table shows the different currents of pool pumps according to their size and the voltage:
|Pump Current @ 230V AC
|Pump Current @ 115V AC
Related Reading: How to Fix Hot Tub Tripping GFCI Circuit Breaker (Repeatedly)
The pump horsepower will also determine the thickness of the wire you need for your pool pump.
Higher horsepower pumps draw more current. Since the current requirements are higher, you’ll need a thicker cable to accommodate this.
Related Reading: Can I Use a Bigger Swimming Pool Pump?
What Happens if the Cable is Too Thin?
Using a cable that is too thin for a pool pump will result in excessive heat running through the cable. This is dangerous. If the circuit breaker is the correct size, it will trip, but if not, it could be a fire hazard. Many electrical fires start because of overloaded cables.
It’s vital you get the right size cable and it is thick enough. It’s better to choose a cable that is too thick, rather than too thin.
Best Wire Gauge for 0.5 to 2.5 hp Pumps
Pool pumps between 0.5 and 2.5 horsepower need a copper cable that is a minimum of #12 AWG and a maximum thickness of #10 AWG if the distance from the breaker board to the pump is less than 50 feet.
For distances 50 to 100 feet, you’ll need #8 AWG to #10 AWG gauge wire.
The cable gauge requirements do vary from location to location, so please consult your local electrician to make sure your cables meet the code.
Other Pool Pump Requirements
In addition to the thickness of the cable, there are some other requirements as listed in the National Electrical Code. Here are some of the most common:
- Pool pumps must be on their own circuit
- Pump power outlets (receptacle) must use a twist lock
- Pump receptacles must be GFCI protected
- Receptacle location should be at least 6 feet (1,829 mm) from the pool edge
Related Reading: How to Fix Pool Pump Tripping Circuit Breaker (Repeatedly)
You should now have a better idea of which size wire to use for your pool pump. Although we’ve taken care to compile this information, it is general in nature. You should consult a licensed electrician in your local area for advice.
Related Reading: Do Hot Tubs Need a GFCI? Rules and Codes for Hot Tubs and Swim Spas