AC (Alternating Current): 1. An electric current that reverses its direction at regular intervals. 2. A flow of electricity which reaches maximum in one direction, decreases to zero, then reverses itself and reaches maximum in the opposite direction. The cycle is repeated continuously. The number of such cycles per second is the frequency.

Activated Sludge: A wastewater treatment process that uses suspended microorganisms to digest the organic contents of wastewater.

Alarm Condition: Condition that warns operator of a problem with system, eg., high water alarm which will activate horn and light.

Alternative On-site System: an on-site treatment system other than a conventional septic tank and leach field design, i.e. sand mounds, sand filters, cluster systems, etc.

Amps: The unit of measure or electrical current flow.

Alternator: Device designed for alternating the run cycle or duplexing of two motors automatically, which equalizes pump wear.

Automatic Pump: Refers to a pump that is controlled with a liquid level switch, pressure switch or control panel automatically for designed conditions.


 A specially constructed component within the WA1000 mercury tilt switch designed to regulate the flow of mercury, resulting in a wide angle between on and off.

Black Water:
 Wastewater from the toilet, which contains most of the nitrogen in the sewage.

BOD (Biochemical Oxygen Demand):
 Measure of the amount of oxygen required by bacteria for stabilizing material that can be decomposed under aerobic conditions. BOD is a commonly used determinant of the organic strength of a waste.


 Insulated wires used to carry an electrical current.

Cable Clamp:
 Device comprised of a stainless steel hose clamp and plastic bracket that secures the float cable at appropriate levels and provides a secure pivot point.

 A term applied to the steel container used for the body of SJE’s mercury tilt switches.

Centralized System:
 A collection and treatment system containing collection sewers and a centralized treatment facility to collect and treat large volumes of wastewater.

Cluster System:
 A decentralized wastewater collection and treatment system where two or more dwellings, but less than an entire community, is served.

Common Stop:
 The lowest float on a duplex pump-down system and the highest float on a pump-up system. Serves to shut off the lead or lag pump or both at once.

Plastic or metal piping used to protect electrical conductors (wires) or cables.

Control Panel:
An enclosure containing pump/motor control components and alarms. Examples of these components might be: contactor(s), relays, timers, terminal strip, alarm components, etc.

Convention On-site System:
 includes a septic tank and a leach field.

Two or more flexible insulated/electrical conductors covered by a flexible insulation.

Cord Conductors:
The individual insulated wires contained within an outer jacket cover of a cord.

CSA (Canadian Standards Association):
 an independent testing laboratory similar to UL in the United States.

 The movement of electrons through a conductor (measured in amps). Its electrical symbol is I.

 (Pump Term) The normal on-off operation of the pump to keep the liquid level at a set point.


DC (Direct Current):
Electrical flow in one direction only (like a battery). It is the flow of charges in just one direction with a fixed polarity of applied voltage.

Decentralized System:
 An on-site or cluster treatment system that is used to treat and dispose of relatively small volumes of wastewater, generally from dwellings and businesses that are located relatively close together.

A flexible material, sensitive to pressure changes relative to liquid levels, which operates a micro-switch to open or close an electrical circuit.

Direct Switching:
 A float pump switch assembly that directly turns a pump on or off without a control panel.

Direct Wire:
 Wiring a float switch directly to a pump or a control panel (without piggy-back plug).

Discharge Pipe:
The pipe that passes the liquid out of the pit or sump. The outlet pipe opposite the suction side of the pump.

Double Pole, Double Throw:
A six-terminal switch or relay contact arrangement that simultaneously connects one independent pair of terminals to either of two other independent pairs of terminals.

Drainage System:
 A system to dump or dispose of liquid waste.

see Subsurface Soil Absorption Field.

Duplex System:
A double pump system where pumping time is alternated between two pumps. When one pump is running the second acts as a stand-by to handle overload or pump failure.


 Partially or fully treated wastewater flowing from a treatment unit or facility.

Electrical Contact:
A physical contact that permits current flow between conducting parts.

Electrical Source:
 The AC voltage from the wall outlet or a generator. The DC voltage from a battery or power supply.

The electric conductor through which an electric current enters or leaves SJE’s mercury tilt switch.

Epoxy Encapsulated Switch:
 The epoxy (casting compound insulator) completely surrounds and protects the mercury tilt switch in many SJE float switches.

External Weight:
 The weight secured to a float switch cable which serves as a pivot point.


The device utilized in alarm systems that flashes the light on and off at regular intervals.

A commonly used term descriptive of a float housing.

Float Housing
Non-corrosive plastic structure that provides buoyancy and encases SJE’s switch assemblies.


Gray Water:
 non-toilet household wastewater (from sinks, showers, etc).

Grinder Pump Pressure Sewer:
Household wastes flow by gravity directly into a prefabricated chamber located either in the basement of a house or outside the foundation wall. The chamber contains a pumping unit with grinder blades that shred the solids in the wastewater to a size that can pass through the small diameter pressure sewers.


Heat Shrink Tubing:
 The tubing used in SJE’s splice kit for making electrical connections. It shrinks upon application of heat and seals the splice from moisture and provides electrical insulation.

High Starting Currents:
Applies to induction type devices such as electric motors that can require one to six times normal running current just to accelerate to full speed (RPM).

Holding Relay:
 Electrical term applicable to a relay that holds the current once closed by the start switch until opened by the stop switch. A holding relay is used in the Double Float® pump switch and many control panels.

Hose Clamp:
 The stainless steel clamp used as a component in securing the switch to the discharge pipe.

Hot Line:
 The “Hot” line or phase has a voltage potential with respect to ground. A 120 VAC system has one hot leg while a 240 VAC system has two hot legs.

H.P. (Horsepower):
 Electrical term for indication of the rate of work performed. H.P. equals 746 Watts (power). One H.P. equals 550 foot pounds of work performed per second (force through distance).


Internal Weight:
 The weight placed inside the float housing of SJE’s internally weighted Sensor Float® control switch. The weight adds stability to the float and serves to create a pivot point.

Intrinsically Safe:
 Intrinsically safe barrier, which is designed to limit the energy (voltage and current) to the sensors in a classified hazardous location, under specified fault conditions.


Junction Box: Term applied to a PVC reinforced box used to contain and protect cable connections.



Latching Relay:
 Latches or holds onto a signal from a momentary or stuttering switch. Has to have an unlatch signal to turn off. A latching relay pump circuit uses an on and an off float to operate.

Leach Field:
 see Subsurface Soil Absorption Field.

(Light Emitting Diode) Warning light device used on Tank Alert® I alarm system.

Lift Pump:
Raises liquid from a lower level chamber to a higher tank or drainage system.

Lift Pump Chamber:
The sump or pit area the pump can directly draw from.

Liquid Level Controls:
Pump and valve controls used for maintaining pre-set liquid levels.

Liquid Sensor:
An input or sensor device designed for pilot duty only.

Liquid Tight Connector:
 A compression fitting that creates a seal around the cable to prevent moisture from passing beyond the fitting.

Low Voltage:
DC or AC voltages, 32 volts or below, which are considered as a safer level than 120 VAC or 230 VAC live voltage. Commonly used on sensor type float switches.


Manual Pump:
Pump without an automatic level switching device.

Manual Pump Operation:
 To turn the pump on and off by hand without automatic controls.

Mechanical Float Switch:
A generic name applied to a mechanically activated switch that is buoyant in liquid and tilted on an axis (pivot point).

Mercury Tilt Switch:
A gravitationally activated, electrical switch.

Mercury Float Switch:
 A generic name applied to a mercury activated switch that is buoyant in liquid and tilted on an axis (pivot point).

Mercury Reservoir:
 The volume of mercury in a tilt switch or the entrapment of mercury in a portion of the switch structure.

Mercury-to-Mercury Contact:
Two mercury pools come together to close the electrical circuit.

Mercury-to-Metal Contact:
 A pool of mercury comes in contact with a steel electrode to close the electrical circuit.

Motor Contactor:
An electro-mechanical power relay used to switch pump load.

Motor Starting Current:
Amount of current needed to start a motor (starting amps or in rush).


National Electrical Manufacturer’s Association. See NEMA ratings in this section.

Normally Closed (NC):
Reverse action switch, when the float is hanging down, the circuit is closed (continuity made).

Normally Open (NO):
Contacts are open (no continuity between the poles) when the float is hanging down.


 A value-measure of electrical resistance in a conductor, element, resistor, etc.

“Omni-Directional” Mercury Tilt Switch: 
Rotating the float switch 360 degrees in its longitudinal axis has no effect on the switch function.

On – Off Ramp:
 Located in the raceway of SJE’s mechanical switches, it allows for the extended pumping range of the SJE PumpMaster® pump switches.

On – Off Tumbler:
A patented feature of the Super Single® pump switch delays continuity of the contacts until the “snap action” of the tumbler. Serves to extend distance between the on-off position providing a wide pumping range.

On-site System:
 a natural system or mechanical device used to collect, treat, and discharge or reclaim wastewater from an individual dwelling without the use of community-wide sewers or a centralized treatment facility.


Piggy-Back Plug:
A molded plug configuration used on SJE’s pump switches which when plugged into an AC power outlet, allows the molded plug of the pump to be plugged into it. This allows the switch to control the pump.

Power Voltage:
 Voltage of the incoming power circuit used in the system. For example the Tank Alert® I alarm’s primary voltage is 120 VAC and secondary voltage is 12 VAC.

Pressure Sewers:
 an alternative wastewater collection system in which household wastewater is pretreated by a septic tank or grinder and pumped through small plastic sewer pipes buried at shallow depths to either a conventional gravity sewer or a treatment system. Two types include Septic Tank Effluent Pump (STEP) and Grinder.

Pump Circuit:
 The circuit in line with the pump and incoming pump power that provides power, control and protection for the pump.

Pump Cycle:
 One complete normal on-off function of the pump.

Pump Down:
 To pump down or lower the level of the liquid.

Pump Up:
 To pump up or raise the level of liquid.

Pump Chatter (Stuttering):
 Very rapidly starting and stopping a pump, relay, motor contacts, etc. which may cause overheating and damage. This is caused by the contact being opened and closed rapidly perhaps due to turbulence.

Pumping Range:
 Difference between pump “on” level and pump “off” level.

Pumping Station:
a pumping facility is used to lift wastewater where topography is too flat or hilly to permit natural gravity flow to a treatment facility.

PVC Plastic (Poly-vinyl-chloride):
Tough, chemically compatible plastic used for pipe fittings, float housings, etc.



Round cylinder in SJE’s mechanical float switches where the steel ball rolls to open or close the contacts.

An electrical-mechanical activated set of contacts used to make or break a circuit when it is electrically activated or deactivated.

Relay Contacts:
 The mechanical poles that make or break a circuit. These are housed in a relay, and activated by relay solenoid.

Relay Control Panel:
A pump control box that uses a control switch to drive a relay to activate a pump or warning device.

 The by-products of wastewater treatment processes, including sludge and septage.

 An electrical device that acts to reduce voltage by resistance.


Secondary Treatment: 
Typical effluent quality achieved by a conventional centralized treatment facility, typically defined as 85% reduction of influent BOD and TSS or 30 mg/l or both; which ever is least. 

Secondary Voltage:
 Generally the lowered (transformed) voltage on a control system. SJE’s Tank Alert® I alarm’s secondary voltage is 12 VAC.

Self Renewing Contacts:
 Refers to mercury-to-mercury contacts because these contacts will not pit or wear as a mercury to metal contact might.

 The solid and semi-solid material resulting from on-site wastewater pretreatment in a septic tank, which must be pumped, hauled, treated, and disposed of properly.

Septic Tank Effluent Pump (STEP) Pressure Sewer:
a submersible pump located either in a separate chamber within a septic tank or in a pumping chamber outside the tank pumps the settled liquid through the collector main. Because the wastewater is treated in a septic tank, the treatment facility may be smaller and simpler than would otherwise be needed.

Sewage Holding Tank:
 A sealed sewage tank that has no drains and must be pumped.

Sewage Lift Pump:
 Pumps the sewage to a higher storage tank, septic tank or transfer system.

Sewage Pump Basin:
 The area where the pump and float switches are located.

Shock Hazards:
Open conductors or terminals that could allow electrical current to pass through flesh to ground.

Simplex Switch:
 A single pump control system.

Single Phase:
 Refers to a circuit energized by a single alternating electric force. Common voltage levels are 120V, 208V, or 240V.

SJOW, SJOW-A (Power Cable):
 UL and CSA approved round neoprene covered power cable for outdoor use. Fourteen gauge cord conductors have 105 strands of 34 gauge annealed copper. Sixteen gauge cord conductors have 65 strands of 34 gauge annealed copper. Exterior of cord is oil and water resistant. Cord carries an electrical rating of 300 volts and a temperature rating of 60 degrees C. (140 degrees F.) in liquid, 90 degrees C. (194 degrees F.) when dry. Low temperature rating is -34 degrees C. (-29.2 degrees F.).

SJ1000 Tilt Switch:
 SJE’s standard tilt switch used in many mercury activated float switches.

 The primarily organic solid or semi-solid product of wastewater treatment processes.

Solenoids (Electro-Magnet):
An inductor that serves as a magnetic force to close contacts on a relay, and also to shift a solenoid control valve.

Single Pole Double Throw (SPDT):
SJE’s mechanically activated float switch that can be wired for normally open or normally closed operation.

Single Pole Single Throw (SPST)
Contact configuration which makes or breaks a single circuit only. Opens and closes a single conductor only.

Starting Current:
The high initial inrush current (amps) required to accelerate motors to operating speed.

 In a duplex system, the float switch that activates a secondary pump or alarm (lag pump) if the lead pump cannot handle the flow.

Float switch that starts the lead pump in a duplex pump system.

 A rectangular shaped piece of brass on which electrical contacts are riveted. Used in SJE’s mechanical switches.

Subsurface Soil Absorption Field:
 a subsurface land area with relatively permeable soil designed to receive pretreated wastewater from a septic tank or intermediate treatment unit (e.g. sand filter). The soil further treats the wastewater by filtration, absorption, and microbiological degradation before the water is discharged to ground water.

Sump Space:
Size of the basin or collection point which determines what float switch can be used effectively.


Terminal Block:
 A grouping of screw terminals used to join AC power circuits, pump circuits, and float switch circuits into a system.

Test Button:
Push button switch on control panels to test warning devices (light and horn).

Three Phase:
 Energy consisting of three alternating electrical forces that differ in phase by one-third of a cycle or 120 degrees.

Total Suspended Solids (TSS)
: A measure of the amount of suspended solids found in wastewater effluent.

Changes AC voltage to a higher or lower level. In the Tank Alert® I the transformer reduces the primary voltage (120 VAC) to a secondary voltage of 12 VAC.

Movement (splashing or inrush impact) of liquid which might affect float switch performance and cause pump chatter.


U.L. Listing:
(Underwriters Laboratories) offers formal recognition that the device or product meets specified standards.

Underground Splice Connection:
 A watertight splice for direct burial which provides electrical insulation for conductors.


Vacuum Sewers:
an alternative wastewater collection system that uses vacuum to convey household wastewater from each connection to a vacuum station which includes a collection tank and vacuum pumps. Wastewater is then pumped to a treatment facility or conventional sewer interceptor. 

Volts, Voltage (V):
 Electrical pressure (potential). Electrical term for value of electrical differential between two points.


Warning Horn:
Audible warning indicator.

Warning Light:
Visual warning indicator.

Waste Water:
 Water that has been used as a vehicle for moving waste or other impurities.

 Electric term for power. One watt equals rate of work of one amp at one volt pressure.

Wide Angle Capsule (WA1000):
 SJE’s mercury tilt switch designed to give a wide angle, or operating range, between on and off contact.

Wire (Copper Braid):
 Extra flexible uninsulated wire used on tilt switch connections of the Super Single® pump switch so as not to interfere with the free tumbling action.

Wire (Gauge Size):
 Conductor sizing system that correlates to current (amp) carrying ability.

Wire (Stranded):
Stranded copper conductors are used where constant flexing is required – solid copper is more economical and used where there is no flexing.

Wire Nuts:
 Hollow screw connectors used to join conductors together.