Question Answer
Before working on any electrical circuits, this device is used to determine if the circuit is live (energized) or dead (de-energized)? Volt meter
This type of testing can be performed on energized or de-energized circuits? Voltage testing
This device is used to test for current? Ammeter
The current is registered as a number of ___ flowing in the circuit being tested? Ampere
The starting currents can be higher than the running currents by how much (in percentage)? 500% to 700%
Resistance in a circuit is called? Ohms
This electrical testing must only be performed in an open or de-energized circuit? Ohms
This testing device requires batteries which supply power for testing? Ohms meters (resistance)
This type of testing is used to check the insulation resistance of a motor, feeder, ground, and circuit wiring? Mega ohms
This device is used for measuring mega ohms? Megger
When testing electrical equipment, a downward trend in the resistance value (mega ohms) indicates that the insulation is? Deteriorating
When testing the insulation resistance (mega ohms) of equipment, circuits must be? Open (de-energized)
Name three controllable conditions that affect the insulating value on electrical equipment? Dirt or grease on the insulation, moisture, and temperature
When equipment is initially put into service, this electrical parameter is recorded and compared to future readings to establish the value of the parameter and the performance of the equipment? Mega ohms (insulation resistance)
These types of devices de-energize electrical circuits whenever abnormal electrical conditions occur (general term)? Protective devices
These electrical protective devices are used to limit the amount of current or voltage surge in order to limit an immediate rise in the temperature of wires? Fuses
These electrical protective devices are used when the current increases beyond the rated amperage? Fuse
This electrical protective device protects the system by melting an internal element which then opens or breaks the electrical circuit? Fuse
For this electrical safety technique, accepted practice is to utilize metallic water and sewer pipes that are known to run underground for a reasonable distance (as opposed to a rod driven into the earth)? Grounding
Most electrical motor starters found in municipal plants are of which type? Magnetic
The most common type of motor found in municipal plants (used to drive equipment such as pumps, blowers, fans, compressors, and chemical feeders)? Squirrel cage induction motor
With this type of pump the mechanical force applied by the impeller to the liquid is converted into pressure head which then drives the fluid through the discharge piping? Centrifugal pump
This type of centrifugal pump develops pressure principally by centrifugal force, and can be used for varying flow and head applications? Radial flow pumps
This type of centrifugal pump develops pressure partly by the centrifugal force of the impeller and partly by the lift of the impeller vanes? Mixed flow pumps
This type of centrifugal pump develops head by the propelling or lifting action of the impeller vanes upon the liquid. These pumps are high capacity and low head pumps? Axial flow pumps
For centrifugal pumps, impellers are matched to the appropriate motor size to ensure that the pump will operate in which manner during normal flows? Peak efficiency
This device is typically installed at the suction piping so that the pump casing (volute) is always charged with water? Foot valve
With this type of centrifugal pump, the impeller has an enclosed design that takes water into the impeller from both sides of the pump? Single stage double suction pump
On a centrifugal pump these are mounted on both the impeller and pump casing to prevent pressure leakage between the suction and discharge chambers of the casing? Wear rings
With this type of centrifugal pump, the upper half of the casing can be removed to inspect the rotating assembly without disturbing the pump bearings or the bearing alignment? A horizontal split case centrifugal pump
This type of pump has the electric motor connected directly to the pump, and the shaft from the electric motor extends into the pump casing which the pump impeller is mounted? Close coupled pump
These types of pumps can be installed in relatively small spaces because of the pump’s compact design, and they are generally less expensive? Close coupled pumps
This category of pumps uses mechanical action to displace or move liquid rather than use centrifugal force? Positive displacement pumps
This type of pump relies on the backward and forward movement of a piston to pump the liquid. Check valves are installed on the inlet and discharge sides of the pump to control the direction of flow? Reciprocating pumps
Two main types of reciprocating pumps are? Piston pump and diaphragm pump
This type of reciprocating, positive displacement pump is usually used for chemical feed applications since it is more accurate when feeding chemical solutions, and can feed into a pipe under pressure? Diaphragm pump
This rotary pump consists of a screw shaped rotor enclosed in a non-moving housing. As the rotor turns, liquid is propelled along the rotor by the displacement of the screw shaped rotor contacting the walls of the housing, and creating cavities in which liquid is transported? Progressive cavity rotary pump
What are the two factors which determine the capacity of a progressive cavity (rotary pump)? The size of the cavity created between the screw shaped rotor and the housing; RPM of the rotor
This type of pump is normally used to pump liquids that have abrasive, heavy, or coarse particles suspended in them? Diaphragm pumps
This type of pump is normally used to pump liquids that have high concentrations of solids, such as sludge from clarifiers? Progressive cavity pump (rotary pump)
This type of valve function is used to control the flow of water entering the discharge piping in order to prevent water hammer? Pump control valves
To attain high efficiency with centrifugal pumps, this replaceable part is mounted on the circumference of the impeller and on the pump casing (outer edge)? Wear rings
Frequent plugging of pump impellers and high power consumption are indications of what problem with a centrifugal pump? High clearance between impeller and volute faceplate (wear rings)
A consequence of worn wear rings in the centrifugal pump is (list two)? Lower pump efficiency and less pumping capacity
This part of the centrifugal pump transfers the mechanical energy developed by the electric motor to the pump impeller? Shaft
The strength and diameter of the pump shaft are selected on the basis of which parameters? Operating torque and brake power (horsepower)
The impeller end; the coupling end; stuffing box; and bearing or journal fits are components of which part of a centrifugal pump? Pump shaft
This part of a centrifugal pump is located between the pump shaft and the pressurized pump casing? Packing (seal)
This component of a centrifugal pump prevents air from entering the pump casing and also prevents water leakage from the pump? Packing (seal)
This component of a pump shaft serves the same purpose as packing glands, but incorporates an O-ring? Mechanical seal
This component of a centrifugal pump supports the shaft and impeller, and they are mounted in the pump casing at one or more points? Bearings
This occurs when excessive forces are applied to the bearing, and the inner and outer rings become misaligned which causes the ball bearing to concentrate its load at one point. This leads to the eventual degradation of the bearing, what is this called? Brinelling
This term related to lubricants defines the temperature at which the lubricant does not flow? Pour point
This term related to lubricants defines the temperature at which the lubricant vaporizes and momentarily ignites? Flashpoint
This term related to lubricants defines the temperature at which a lubricant vaporizes, ignites, and continues to burn? Fire point
This term is related to lubricants, and it determines the acid forming characteristic? Neutralizing number
This substance related to machinery and equipment tends to break down and become acidic thus forming deposits, and causing corrosion and sludging? Oil (lubricants)
This part of a gate valve seals the upper portion of the valve and allows the valve disc room to rise above the valve port to the full open position? The bonnet
This type of valve requires a packing gland which seals the valve stem? Gate valves
This type of valve is not used to control flow and should be in either the open or closed position only? Gate valve
What problem damages gate valves if they are used to control flow, and which part of the gate valve is damaged? Cavitation (downstream side); valve disc, valve body, and other components
This type of valve has a valve disk that is mounted perpendicular to the valve stem, and seats flat on the valve body mating surface? Globe valve
This type of valve has a unique design which allows it to be used for a number of other functions associated with controlling flow and pressure? Globe valve (hydraulically controlled)
With this valve, flow is controlled by a flexible diaphragm separating the upper control chamber from the lower control chamber? Globe valve
Pressure reducing; pressure relief; pump control; flow control; and pressure sustaining are conditions that can be controlled by the function of a specific type of valve? Globe valve (hydraulically controlled)
Describe the valve function that is used to decrease pressure from a high pressure region of the system to a lower pressure region? Pressure reduction (Globe valve)
Which type of valve function uses pressurized water in and out of the upper chamber of the valve to control the diaphragm accordingly? Pressure reduction (Globe valve)
Which part(s) of a valve assembly, used in a pressure reduction application, functions by directing the flow of pressurized water into the valve assembly in order to adjust pressure levels? Pilot pressure control valve and control circuits (Globe valve)
The pressure relief function on a valve is used to protect which piece of equipment? The globe valve itself
Large capacity pumps with accompanying high velocity flows use this device to control this water pressure related problem that can damage pipes and equipment in the treatment facility (two answers)? Pump control valves; water hammer (Globe valve)
This device can be used when flow rate is critical for a specific application? Flow control valve (Globe valve)
This valve is typically used in applications to control the flow rate, such as influent flow rate of filters, backwash flow rates, etc. What is the application, and what is the type of valve? Flow control valve (Globe valve)
This device has an orifice plate that is normally incorporated into the downstream piping and pressures are sensed upstream and downstream of the orifice plate, which modulates valves to provide a constant flow rate? Flow control valve (Globe valve)
This device is used where the upstream system pressure must be maintained within a certain pressure range. What is the application called, and what type of valve is used? Pressure sustaining valve (Globe valve)
This type of valve function is typically used on a distribution system where upstream pressures must be maintained whenever heavy demand occurs on the downstream side? Pressure sustaining valve (Globe valve)
This type of valve is mainly used to control flow? Butterfly valve
This device allows water to flow in one direction only. They close to prevent flow if movement stops or comes to reverse direction? Check valves
This type of check valve has either a single or double movable disk mounted perpendicular to the flow, and these are seated against the valve body. The valve disc operates either by gravity, a weighted lever, or external spring-loaded weighted system? Swing check valve
This valve uses a cam-shaped plug within eccentrically raised body seat? Eccentric valve (plug valves)
This type of valve throttles the upstream flow and maintains a smooth flow path during closing? Eccentric valve (plug valves)
This type of valve provides high flow capacity, no lubrication, good wear resistance, and favorable throttling performance? Eccentric valve (plug valves)
These are designed to release or admit air into piping systems? Air or vacuum relief valves
How may air enter into a system (list four entry points)? Through pump suction; pumps; packing glands; and joints
If this accumulates at high points into a piping system, as it builds up in the line it restricts the flow of water in the pipe. In extreme cases it can stop flow completely? Compressed air
This device has a floating ball that is connected to a stopper which covers an orifice, and this orifice is an opening to the atmosphere. What is this device and what is its purpose? Air release valve; release pressurized air from a piping system
Under conditions where pipelines are filled or drained, these devices are typically installed to prevent damage to the piping? Air and vacuum relief valves
These devices are essentially strain gauges that deflect according to the forces exerted on them? Pressure gauge
These pressure sensors have mercury switches incorporated into the gauge. Variance in pressure causes the mercury switch to tip and either close and stop the pump, or to open and start the pump? Bourdon type pressure sensors
This type of pressure switch senses pressure with a bottom transducer, and pressure is mechanically transmitted to the switch in the upper half of the instrument? Fulcrum type sensing pressure switch
These types of devices are used primarily to measure air and other pressurized gases in a usable range from 0 to 207 kPa (0 to 30 psi)? Bellow gauges
These devices are used to measure low pressure in the range of 0 to 28 kPa (0 to 4 psi)? Diaphragm pressure gauge
These are used to isolate the pressure switch from corrosive liquids, and these are used in sewage related applications and chemical feed systems to prevent corrosion and damaging fluids from contacting the pressure switch? Isolating diaphragms
These are probably the most common types of sensors and controllers in municipal plants? Level sensing systems
This type of level sensor is connected by cable to a rotating drum mounted above the water surface, and a counterweight balances and stabilizes the device as it moves vertically on the water surface? Float type level sensor
This is incorporated around a float type level sensor in order to dampen unwanted turbulence or waves? Stilling well (surrounds the flow)
Vertical movement of this float rotates the drum, and cams mounted in the control unit open and close circuits to adjust liquid depths? Float type level sensor
This type of level sensor is suspended from a hangar at a desired height above or below a water surface, and changes of the water level tip a float which contains mercury and consequently open or closes a circuit? Mercury switch
This type of level sensor uses compressed air to measure liquid depths, whereby hydrostatic pressure created by liquid depth is sensed by the air pressure needed to overcome the liquid pressure? Bubbler system
This is mounted above the water surface and emits a high-frequency sound at predetermined intervals and measures the time for the sound to be reflected from the water surface. The time duration is a function of the distance from the transducer to the liquid level. What type of level sensor is this? Sonic level sensor
This type of flowmeter is positioned in the flow stream and relies on the force of the flowing water to generate a rate of speed (RPM) that is directly proportional to the rate of flow, and requires mechanical gears and gauges to register the flow rate? Propeller flow meter
This type of propeller flow meter uses ____ instead of mechanical gears and gauges to register the flow rate. The magnitude of the electrical signal generated by the _____ is proportional to the speed at which the propeller rotates, and the electrical signals are converted to correspondent flow rates (same word for both blanks)? Magnets
Propeller flow meters are categorized as what type of flow measuring device? Velocity sensing flow meter
Flow rate is measured when water flows through a restricted passage which exhibits a slight pressure loss. These devices use venturis and orifice plates in pipes to create these restricted passages? Differential pressure sensing devices
This type of flowmeter senses flow by measuring the electric current induced by flowing water? Magnetic flowmeter
This type of flow meter transmits pulses that are received by a transducer on the opposite side of the pipe (a 45° angle), and the relative time for the sound traverse the calibrated gap is influenced by the flow rate of water? Sonic flow meter
This type of flow meter is used for household services up to 5 cm (2 inches) in diameter. Volume is measured by the filling of the chamber having a specific volume. Each filling/emptying of the chamber registers a movement on the meter gauge, and this basic design allows for measuring volumes over wide variations in flow rate? Displacement meter (used for distribution)
These flow meters are able to measure volume despite wide fluctuations in flow, and combine features of both displacement and velocity meters. Upon increasing flow rate and head loss across the displacement meter, a type of valve opens and permits flow to the velocity meter (type of valve/type of flow meter)? Compound valve; compound flow meter

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