Red Lion by Franklin Electric 1 HP Submersible Deep Well Pump Control Box

Q: what is the purpose of the control box and can it be eliminated?
by Armand from Ohio on July 09, 2012

A: Three wire submersible motors require a control box. Control boxes contain a starting relay, starting capacitors and in some cases overload protectors. Two wire submersible motors have these components built into them and do not require a control box.

One benefit of using a three wire motor with a control box is that some of the components that are subject to failure are located above ground where you can get to them without pulling the pump.

Control boxes should never be mounted in direct sunlight or in locations that are extremely hot, this causes the capacitor life to be shortened and can cause nuisance overload trips. Do not mount the control box in a humid location such as a damp well pit since voltage breakdown and corrosion will accelerate component failure in this condition.

Control boxes are designed for vertical, upright mounting only. Any other position will affect the operation of voltage sensing relays in larger sizes and may result in water leakage.
by Jim, Product Expert