Online Store


"T" Frame: Current NEMA designation identifying AC induction motor frames. (NEMA has dimension tables which offer standard frame measurements.) Replaced the previous standard "U" frame in 1965.

T.D.H.: Total discharge head. A combination of the suction head and the head being produced by the pump.

Tail pipe: The pipe added below the jet assembly, in a weak well application. (See weak well)

Tamperproof: Meaning that tools are required to alter or remove portions of the equipment.

Tandem seals: The seals are facing in the same direction with a low-pressure barrier fluid circulating between them.

Tank: A steel, plastic, or fibrewound vessel designed to store pressure or water.

Tannin: Any of a group of water soluble, natural organic phenolic compounds that are produced by metabolism in trees and plants and are part of the degradation-resistant fulvic acid materials formed during the decomposition of vegetation. Tannins occur in water or in almost any location where large quantities of vegetation have decayed. Tannins can impart a faintly yellowish to brown color to water. Tannin molecules tend to form anions in water above pH 6 and can be treated with anion exchange resins. Below pH 5, tannins are better treated with activated carbon.

Taper Charge: A charge regime delivering moderately high-rate charging current when the battery is at a low state of charge and tapering the current to lower rates as the battery becomes more fully charged.

Taste And Odor: A type of filter that makes water smell and taste better.

TDH: Total Dynamic Head: The total amount of head required by the system. The amount of head the pump must produce to properly operate the system.

TDS: See Total Dissolved Solids

TDSL: Total Dynamic Suction Lift – equivalent to Head.

Tee: A plumbing fitting used to bring two pipes together into one, or vice-versa.

TEFC: Totally Enclosed Fan Cooled: a type of motor enclosure.

TEFLON (PTFE): PolyTetraFluoroEthylene has outstanding resistance to chemical attack by most chemicals and solvents. PTFE has a temperature rating of -20°F to 400°F in valve applications. PTFE, a self lubricating compound, is used as a seat material in ball valves. TEFLON is a registered trademark of the DuPont Company.

Teflon: Teflon is a registered trademark of DuPont and is used in relation to products manufactured with DuPont’s fluoropolymer resins. Teflon has a low coefficient of friction, excellent insulating properties, and is chemically inert to most substances. It also can withstand high heat applications and it is well known for its anti-stick properties.

TEFLON® (PTFE)-1-:  Polytetrafluoroethylene has outstanding resistance to chemical attack by most chemicals and solvents. PTFE has a temperature rating of -20°F to 400°F in valve applications. PTFE, a self lubricating compound, is used as a seat material in ball valves. TEFLON is a registered trademark of the DuPont Company.

Tensile strength: The strength measured when the part is being pulled axially.

TENV/TEFC: "totally enclosed non-vented" (TENV). Larger motors have a fan to blow air over the outside of the motor housing and are called "totally enclosed fan cooled" (TEFC).

Terminal Board: The place where the power is connected to the motor, and in most cases is where the voltage selection is made.

Terminals: The parts of a battery to which the external electric circuit is connected.

Tertiary wastewater treatment: Selected biological, physical, and chemical separation processes to remove organic and inorganic substances that resist conventional treatment practices; the additional treatment of effluent beyond that of primary and secondary treatment methods to obtain a very high quality of effluent. The complete wastewater treatment process typically involves a three-phase process: (1) First, in the primary wastewater treatment process, which incorporates physical aspects, untreated water is passed through a series of screens to remove solid wastes; (2) Second, in the secondary wastewater treatment process, typically involving biological and chemical processes, screened wastewater is then passed a series of holding and aeration tanks and ponds; and (3) Third, the tertiary wastewater treatment process consists of flocculation basins, clarifiers, filters, and chlorine basins or ozone or ultraviolet radiation processes.

Test Kit: A method used to test the water balance and sanitizing level of your pool water.

Theoretical Suction Lift: The maximum height (33.9') that water can be lifted inside a tube under perfect conditions (perfect vacuum) at sea level. At this point, the water inside exerts a pressure equal to the weight of the atmosphere pushing down on the ocean’s surface. Theoretical suction lift is calculated by dividing the atmospheric pressure at sea level (14.7 lbs. per square inch) by the weight of one cubic inch of water (.0361 lbs.). This equals 407.2" or 33.9'.

Thermal conductivity: A measure of the material's ability to conduct heat. This is a very important factor in the selection of mechanical seal faces.

Thermal Limit: The maximum internal operating temperature in an electric motors, determined by the class of insulation used.

Thermal pollution: A reduction in water quality caused by increasing its temperature, often due to disposal of waste heat from industrial or power generation processes. Thermally polluted water can harm the environment because plants and animals can have a hard time adapting to it.

Thermal Protector: A thermal protector, automatic or manual, mounted in the end frame or on a winding, is designed to prevent a motor from getting too hot, causing possible fire or damage to the motor. Protectors are generally current and temperature sensitive. Some motors have no inherent protector, but they should have protection provided in the overall system's design for safety. Never bypass a protector because of nuisance tripping. This is generally an indication of some other problem, such as overloading or lack of proper ventilation. Never replace nor choose an automatic-reset thermal overload protected motor for an application where the driven load could cause personal injury if the motor should restart unexpectedly. Only manual-reset thermal overloads should be used in such applications.

Thermal Runaway: A condition whereby a cell on charge or discharge will destroy itself through internal heat generation caused by high overcharge or high rate of discharge or other abusive conditions.

Thermally Protected: Mechanical safety device in the motor to prevent overheating.

Thermoelectric power water use: Water used in the process of the generation of thermoelectric power. Power plants that burn coal and oil are examples of thermoelectric-power facilities.

Thin Film Composite: A membrane made with a polyamide-based polymer consisting of three layers: a polyester support web, a micro porous polysulfonic inter layer, and an ultra-thin barrier coating on the top surface.

Third Affinity Law: With the same impeller, the change of horsepower will be related to the cube of the change in the velocity of the liquid; if you increase the speed of the water the horsepower required to affect that change will be cubed.

Thixotrophic fluid: The viscosity of the fluid decreases with agitation. Non drip paint is an example of such a fluid.

Thixotropic: The property of a fluid whose viscosity decreases with time.

Three Phase Motor: A type of electric motor that does not have starting windings; coil sets are in groups of three instead of two.

Three States of Water: Liquid; Vapor or gas; Solid

Thrust bearing: Designed to take the axial thrust in pump applications. It is usually located next to the coupling and is often supplied in a "double row" configuration.

Thrust bearing: Locates the rotor or shaft axially. Normally located close to the coupling.

Thrust Bearing: Special bearings used to handle higher than normal axial forces exerted on the shaft of the motors as is the case with some fan or pump blade mountings.

Thrust: In a centrifugal pump it refers to the axial movement of the shaft. The thrust can be towards the wet or power end of the pump and at start up it thrusts in both directions.

Thyristor: Same as SCR: a solid state device containing a gate that acts as the "turn-on" switch that allows the device to fully conduct voltage.

Time Clock: A mechanical device that controls the timed operation of your electrical equipment, primarily your filter and booster pumps.

Time: The measure of delay between two events.

Timer: Also known as a controller. It is the part of the automatic sprinkler system that signals the valves when to turn on and how long to run.

Titratable Alkalinity: The quantity of hydrogen ions (H+), which must be added to a sample of alkaline water in order to establish a condition of neutrality.

Titration: A method of testing for total alkalinity, calcium hardness and acid/base demand by adding a titrant, drop by drop until a color change is observed.

TNS: Test, Normal, Silence: A toggle switch used to turn the alarm on for a test, normal means the alarm is on and when the float that runs it is in the up position it turns the alarm on. Silence means the audio and visual alarm has gone off and you're working on it and don't want to hear the audio anymore.

Torque: A turning or twisting effort that results from a force being applied to a rigid object at a radial distance from the center of rotation. Torque = (force) times (radial distance).

Torque-1-: A twisting or turning effort that results from a force being applied to a rigid object at a radial distance from the center of rotation.

Torque-2-: The turning effort or force applied to a shaft, usually expressed in inch-pounds or inch-ounces for fractional or sub-fractional HP motors. The rated horsepower is what is important for continuous service. Additional ratings may be important if the motor must start against a large load, or may sometimes be significantly overloaded. Since the primary problem with an overload is thermal, a properly designed motor can tolerate an overload if it is short enough and the motor then has sufficient time to cool down before the next one. These ratings are specified as torques instead of power, were torque is rotational force. The start-up torque and pull-up torque are related to the motors ability to overcome inertia when starting loads. The break-down torque tells how much overload can be tolerated before the motor stalls. Note that the break-down torque only applies to a transient load; the continuous load still may not exceed the rated power times the service factor. And if the break-down torque is used, the current will be quite high for that time.

Total  Head: Identical to Total Dynamic Head.  Total head is the sum of the dynamic suction head and the dynamic discharge head.

Total Alkalinity: The ability of the pool water to resist changes in pH. The "buffering" capacity of the water. Additions of Sodium Bicarbonate will increase the levels, expressed in ppm.

Total Discharge Head: The total pressure or head the pump must develop on the discharge side. It is the sum of the elevation, the service pressure, and the friction loss. Of course, all of these measurements must be expressed in the same units, usually feet of head, before adding them together.

Total Dissolved Solids (TDS): A measure of everything that has ever dissolved in the water; all the matter that is in solution. High TDS levels can oversaturated your water, causing all sorts of reactions.

Total Dissolved Solids-1-: The sum of all ions in a solution, often approximated by means of electrical conductivity or resistance measurements. Total dissolved solids (TDS) measurements are commonly used to assess distiller and reverse osmosis unit performance. It is important to note that a test measuring the electrical conductivity of the water sample provides only an estimate of the TDS present, as conductivity is not precisely proportional to the weight of an ion and nonconductive substances cannot be measured by electrical tests.

Total Dynamic Head (TDH): Is the sum of the static head or lift, plus the head needed to overcome friction in the piping and head required to operate the system.

Total Dynamic Head (TDH)-1-: The sum of the dynamic suction head and the dynamic discharge head. Also referred to as Total Head.

Total Dynamic Head: The dynamic suction head plus the dynamic discharge head. Also known as Total Head.

Total Dynamic Head-2-: The total amount of resistance to flow against which a pump must work OR the sum of all the losses the pump must overcome to make the system work. Its components are Suction Head (Static suction lift, Suction side friction loss, Draw down) and Discharge Head (Static discharge head ((or elevation)), Discharge side friction loss, Head or pressure required at the point of usage.

Total Dynamic Head-3-: Identical to Total Head. This term is no longer used and has been replaced by the shorter Total Head.

Total Effective Length Of Pipe: The sum of straight pipe lengths plus fitting friction loss, which has been converted into straight lengths of pipe.

Total head: The amount of head produced by the pump. Discharge head minus suction head. If suction head is a negative number it is added to the discharge head.

Total Head-1-: The dynamic suction head plus the dynamic discharge head. Also known as Total Dynamic Head (TGH).

Total Head-2-: The sum of discharge head, suction lift and friction losses.

Total Head-3-: The difference between the pressure head at the discharge and suction flange of the pump ( syn Total Dynamic Head. pump head, system head)

Total Organic Carbon: A measurement of the total mass of dissolved carbon in a water sample, excluding that originating from carbon dioxide and carbonates.

Total Static Head: Consists of the physical dimension of the static discharge head plus or minus the static suction head.

Total Static Head-1-: Is the difference between the discharge and suction static head including the difference between the surface pressure of the discharge and suction tanks.

Total Static Head-2-: The difference between the discharge and suction static head including the difference between the surface pressure of the discharge and suction tanks if the tanks are pressurized.

Total Suction Lift: Total Suction Lift = Vertical Lift + Friction loss. Total Suction Lift is also called "Suction Conditions"

Total Suspended Solids (TSS): A measure of the amount of suspended solids found in wastewater effluent. The particles, which can be removed from a solution by filtration, usually specified as the matter which will not pass through a 0.45 micron pore-diameter filter.

Totally Enclosed Air Over (TEAO): Special motor used to drive a fan blade. Has no external fan and is dependent on air stream of driven fan for cooling.

Totally Enclosed Fan Cooled (TEFC): Has an external fan to move cooling air over the motor. Suitable for outdoor and dirty locations.

Totally Enclosed Non-Ventilated (TENV): Does not have external cooling fan but is dependent on radiation and convection for cooling.

Toxic: Meaning that a given substance has an adverse physiological affect on man.

Transformer: A device which converts electrical power (alternating current) to electrical power of a different voltage. In this device, both primary and secondary windings are usually stationary and are wound on a common magnetic core.

Transient, Non-Community Water System: A water system which provides water in a place such as a gas station or campground where people do not remain for long periods of time. These systems do not have to test or treat their water for contaminants which pose long-term health risks because fewer than 25 people drink the water over a long period. They still must test their water for microbes and several chemicals.

Transmissibility (ground water): The capacity of a rock to transmit water under pressure. The coefficient of transmissibility is the rate of flow of water, at the prevailing water temperature, in gallons per day, through a vertical strip of the aquifer one foot wide, extending the full saturated height of the aquifer under a hydraulic gradient of 100-percent. A hydraulic gradient of 100-percent means a one foot drop in head in one foot of flow distance.

Transpiration: Process by which water that is absorbed by plants, usually through the roots, is evaporated into the atmosphere from the plant surface, such as leaf pores. See evapotranspiration.

Trash Pump: Designed to handle large amounts of debris, with a solid handling capability of 25% by volume. As a rule of thumb, trash pumps can handle spherical solids up to one-half the diameter of the suction inlet.

Tread Contact Surface: Foot contact surfaces of a ladder, step, stair or ramp.

Treads, Recessed: A series of vertically spaced cavities in the pool, spa or hot tub wall creating tread areas for step-holes.

Treatment Technique: A required process intended to reduce the level of a contaminant in drinking water.

Tributary: A smaller river or stream that flows into a larger river or stream. Usually, a number of smaller tributaries merge to form a river.

Trichloro-S-Triazometrione: A chemical compound used as an industrial disinfectant, bleaching agent and a reagent in organic synthesis. This white crystalline powder, which has a strong "chlorine odor," is sometimes sold in tablet or granule form for domestic and industrial use.

Trickle Charging: A method of recharging in which a secondary cell is either continuously or intermittently connected to a constant-current supply that maintains the cell in fully charged condition.

Trowel: A pool trowel is a flat-bladed tool with rounded ends used to apply viscous or particulate material coatings to concrete, especially on pool decks.

Tungsten carbide: A common hard face seal material available in several grades depending upon hardness and corrosion resistance. Cobalt and nickel are the two most common types.

Tungsten carbide: A common hard face seal material available in several grades depending upon hardness and corrosion resistance. Cobalt and nickel are the two most common types.

Turbidity: A measurement of the amount of suspended solids (colloids) in a solution. Caused by stirred-up sediment, silt, clay, etc. Turbidity blocks light rays and makes the water opaque. Turbidity is measured in Nephelometric Turbidity Units (NTU). Potable water should not exceed 0.3 NTU. Turbidity cannot be directly equated to suspended solids because white particles reflect more light than dark-colored particles and many small particles will reflect more light than an equivalent large particle.

Turbidity-1-: Cloudy, dull, hazy water, due to micro particle suspension.

Turbidity-2-: The amount of solid particles that are suspended in water and that cause light rays shining through the water to scatter. Thus, turbidity makes the water cloudy or even opaque in extreme cases. Turbidity is measured in nephelometric turbidity units (NTU).

Turbine Bowl: A component of a submersible pump that houses an impeller. Often stacked in multiple stages.

Turbulence: Disturbed fluid. Can cause cavitation problems in a centrifugal pump. Often caused by an elbow located too close to the pump suction inlet.

Turbulent-1-: a type of flow regime characterized by the rapid movement of fluid particles in many directions as well as the general direction of the overall fluid flow.

Turbulent-2-: The behavior of fluid articles within a flow stream characterized by the rapid movement of particles in many directions as well as the general direction of the overall fluid flow.

Turnover: The amount of time it takes your pump to move all the water in your pool through the filter and back again. Usually, pools are designed for an eight hour turnover.

Turnover-1-: The period of time (usually in hours) required to circulate a volume of water equal to the pool, spa or hot tub capacity.

Two Sides To A Pump: Suction Side (How does that water get in there?) - the pump moves the water so that the low pressure has to be filled from another source. If we get the pressure low enough at the eye of the impeller, the atmosphere will push the water from our source to the pump; Discharge Side - the side that moves the water away from the pump.

Two way balance: A method of balancing a mechanical seal in two directions. A very important consideration in dual seal applications.

Two-pole motor: Motors with one pair of running windings that run at 3450 rpm.

Types Of Suction Lift - Negative lift, meaning that the pump is above the water and has to have the water pushed up to it by the atmosphere; Positive lift, meaning that the pump could be submersible or has water above it.