What Role Does A Sump Pump Switch Play?
Usually, the sump pump sits in a sump pit, which is like a large well with several holes in its wall. These holes collect water into the sump pit (or basin) through connection to various drainage pipes within an estate or establishment. As different waters drain into the sump basin, the water level rises. A sump pump switch or trigger is a smart electromechanical device that tracks the rising water level in the pit and turn-on the sump pump when water reaches a predetermined height
As the sump pump continues removing water, the water level in the sump basin comes down. When the water level drops below a preset height, the sump pump switch stops the pump.
So, a sump pump switch's job is to start and stop a sump pump automatically without requiring human intervention.
What Are The Types of Sump Pump Switches?
There are various types of switches used in sump pumps. Based on their working principle, sump pump switches have two broad categories, which are.
Further, float action switches are of three types as
Electrical pump switches are of two types as
How Does Each Type of Sump Pump Switch Work?
Vertical Action Float Switch: Sump pump vertical switches have a simple design consisting of a floating ball, a vertical rod, and a switching component in a housing. A few easy steps are sufficient for its installation and alignment. The rod attaches to the pump's body or the discharge pipe while the switch moves on the rod. Vertical float switches employ a very simplified work procedure. The rise of the sump pit's water level pushes the floating ball up to a higher level. Upon reaching a certain predefined height, the float ball activates the switch, automatically turning on the pump. The running pump removes water, so the water level in the sump pit decreases. Due to the falling water level, the float moves below a preset level. As a result, the switch disengages that turns off the pump.
Tether Activated Float Switch: Tethered float switches are popular because they have lesser cost and a simplistic operation. A tethered float switch comprises a hollow floating element holding a steel ball or mercury inside and a cord that attaches to the pump or the sump pit's lid. Despite mercury-enabled switches being cost-effective, they lose preference nowadays due to environmental concerns.
Due to the rising water level in a sump basin, the floating body pivots, and gravity causes the inner ball to move to the bottom and trigger the electrical switch, activating the pump. As the water level in the sump basin comes down, the float returns to its low position. When the float element rests at its low, the inner ball moves to disengage the float switch and shut off the pump.
Sump pumps with tethered float switches get longer off time between pumping cycles allowing better cooling of the motor. It means a pump will have a longer working life. However, tethered switches require regular inspection against locking to debris, pinning to the wall, tangling and burnout. This type of switch needs a wider sump pit for installation.
Diaphragm Movement Float Switch: A diaphragm switch consists of a membrane that senses water pressure in the sump pit and activates or deactivates the diaphragm switch accordingly. It affixes very low on the pump's side or body. When the rising water level in the sump pit increases pressure on the membrane, it curves inward or compresses. The compressed membrane energizes the switch and turns on the pump motor. A falling water level decreases pressure on the membrane, so it decompresses or inflates. The inflated membrane disengages the diaphragm switch and turns off the pump. Diaphragm switches warrant less oversight and comfortably fit into congested sump pits.
Electronic Pump Switch: Electronic sump pump switches sense the presence or absence of water through a wire probe. It detects a change in resistance due to current flow and turns the pump on or off accordingly. The switch mechanism applies a bit of current to the probe. As the water level in a sump basin rises, the switch probe gets submerged in water. Upon sensing the presence of water, the wire probe energizes the electronic switch turning on the pump. Due to falling water levels in a sump basin, the wire probe emerges out of the water at some point which disengages the electronic switch and shuts down the pump motor. Higher and lower water levels for electronic pump switches are programmable. Electronic pump switches are more reliable and accurate because they do not require movement.
Also Read: How to Test Your Sump Pump
Microprocessor Controlled Pump Switch: A microprocessor-controlled switch is also known as an ion digital level controller. This switch is technologically sophisticated. It has two sensors, a proprietary sensor and a digital float sensor driven by a microprocessor. The proprietary sensor senses the presence of water or water pressure and electro-mechanically converts the reading into an analog electrical signal. The electrical signal proportionally varies according to the water level. Then the analog electrical signal from the proprietary sensor is fed to the digital float sensor. The microprocessor in the digital float sensor converts the analog signal into a digital signal.