Swimming Pool Blog
Rob Cox, March 11, 2012
How to wire a variable speed pool pump
Wiring a variable speed pump, sounds intimidating, but don't let the title scare you. It's actually quite simple to wire up a new variable speed pool pump, either from Pentair (Intelliflo pictured, left), or Hayward.
This will be a short topic, because wiring a variable speed pump is less complicated than wiring a 2 speed pump, which requires a different time clock, and an extra (low speed) wire.
To wire a new Intelliflo or EcoStar pool pump, you can wire it directly to a circuit breaker on the electrical sub-panel. The breaker should be a two-pole breaker, for two wires, and should be a 15 or 20 amp breaker (this number is printed on the breaker switch).
If you are using a standard timeclock, pictured at right, you can continue to run power through a 220V timeclock, directly into your new variable speed pump. You should remove the timer dogs and discontinue use of the clock as a switch. Intelliflo and EcoStar pumps have their own timeclocks, so you will use the on-board clock from now on to control the pump.
Variable speed pumps don't get wired into the back rear of the motor, like standard pool pumps, but rather into the Variable Drive unit. On the side of the box or control panel mounted onto the motor is where we are going to bring the 2 hot leads or wires, from the breaker.
Attach the flexible conduit fitting onto the drive motor housing, and connect both wires, attaching them to L1 and L2. It doesn't matter which wire connects to L1 or L2. The ground wire should attach to the green screw. So essentially, wiring a variable speed pump is the same as wiring a standard pump, except that you don't need a timeclock. And you have to use 230V, or two wires each carrying 115V, rather than one 115V line and one neutral line.
Make sure you bond your new variable speed pump, while wiring it up. Bonding is different than the ground wire that you connect to the green screw inside the drive motor. A bonding wire is a bare copper wire, that sticks up out of the concrete or is attached to a piece of rebar.
When inground pools are built, this bonding wire is installed, and it connects the pool rebar, pool light, the ladder or slide sockets, with the metal or electrical components on the equipment pad. This circuit, made by the copper wire, is connected to a sunken grounding rod. If stray electricity or a lightning strike were to occur, a properly bonded system would ground the charge, and protect the equipment.
So, there you go, piece of cake to wire up a variable speed pump in place of a standard pump. Told you it was going to be easy! Configuring your new pump options will likely take you longer - but that's a topic for another day. And so is, wiring a two-speed pump, that's quite a different operation.