Industrial Maintenance Review – Electrical, General, HVAC, Controls, Plumbing, Structural & Mechanical

67 question-and-answer flashcards covering key points from the Electrical, General, HVAC, Controls, Plumbing, Structural and Mechanical sections of the lecture notes.

What units are transformer capacities normally rated in?

KVA

In safety procedures, what does LOTO stand for?

Lock Out Tag Out

What does a diode do in an electrical circuit?

Permits current to flow in one direction only

Which instrument is used to measure the speed of a motor?

Tachometer

An LB condulet is primarily used as what fitting?

A 90-degree elbow

Most power distributed in an industrial facility is what phase?

Three phase

When the liquid level is low in a lead-acid storage cell, what should you add?

Only distilled water

What is a contactor?

An electrically controlled switch

Do the neutral and ground conductors serve the same purpose?

False

To change the rotation of a three-phase motor, what should you do?

Change any two input power leads

According to the NEC, a hazardous location is where what exists?

Flammable vapors or gases exist

Must a disconnect be within sight of the equipment it serves?

True

If one overload trips in a three-phase motor control circuit, what happens?

The motor will not be allowed to run

Describe a 3-pole single-throw device.

Three poles move as one single action to two output contacts

What is a relay?

A device that operates another electrical circuit

Must exit lights be tested every month?

True

Where are the most important drains located in compressed-air piping?

At the end of mains

Why is an aerator installed on a water faucet?

To reduce water splash

Is CPR training an OSHA requirement for all people working on electrical systems?

False

What is the best method for preparing new galvanized metal for painting from the options listed?

Spray with cleaning solvent and wipe dry

Tri-sodium phosphate is a well-known what?

Cleaning agent

Are safety vests NOT required when temperatures exceed 90 °F?

False

Do drop-in ceiling panels form a fire break?

False

What are the most common forms of screw head?

Slotted and Phillips

When applying compound to a gypsum wallboard joint, what should you always do?

Feather compound out from the center

An automatic expansion valve controls what?

The suction pressure

If you find a noisy compressor, what should you check for?

All of the above – broken valves, low oil charge, slugging refrigerant

Moisture in a refrigeration system could cause what problem?

Freezing at the expansion valve

Moisture in the insulation of a refrigerated space would do what?

Decrease efficiency of the refrigerated space

Which statement is NOT true about a condenser coil?

The coil is typically in a conditioned room

One purpose of evacuating a refrigerant system is to do what?

Remove non-condensable gases

A ton of refrigeration per hour equals what?

All of the above – 288,000 BTU/day; 200 BTU/min; 12,000 BTU/hr

Which statements about an evaporator are true?

All of the above (low-side coil, after TXV, air moves across for cooling)

Which listed refrigerant is NOT used for modern refrigeration?

R-22

In HVAC, what is a TXV and what does it do?

Thermostatic Expansion Valve

Does a motor controlled by a VFD need a clutch brake?

False

In ladder logic, what does 1:3/3 indicate?

Input rack 3 bit 3

VFD devices control a motor’s what?

Speed and torque

Does a PLC need to be programmed?

False

A VFD controls what aspects of the power fed to a motor?

Both frequency and voltage

What is a discrete input?

An input device incorporated into a PLC

In PLC programming, what does FIFO stand for?

First In First Out

What takes place in a single scan of a PLC?

Inspection and update to the inputs-outputs table

In controls, what do the initials DIO stand for?

Digital Input/Output

What is an SCR?

All of the above – converts AC to DC, gate-controlled, Silicon Controlled Rectifier

Sweating a copper pipe refers to what?

Soldering

What term describes the slope or pitch of a pipe?

Grade

What is a strap wrench?

A tool using a strap that wraps around a pipe to turn it

Does a flush valve use an internal diaphragm to determine flush time?

True

When can flux be used in the brazing process?

Both when brazing copper to brass and copper to copper

A fitting that sits inside the hub of another fitting to reduce its size is called what?

Bushing

A backflow preventer is installed to do what?

Prevent water from flowing in reverse

One trap arm may serve how many P-traps?

2

Valves on fire systems should be of which type?

OS&Y (Outside Screw & Yoke)

Flexible water connections are required to be what?

Readily accessible

What is the standard distance between studs in interior walls?

16 or 24 inches on center

In construction, what is the 3-4-5 method used for?

To find a right angle

On a properly installed conveyor belt that needs tracking, which roller should be adjusted?

Tail roller

To what level should a standard gearbox be filled with oil?

To the center of the bottom shaft

Is rough top belt used only in wet applications?

False

Which of the following would NOT cause a motor overload trip on a conveyor motor starter?

Short in the start-stop circuit

A merge belt is what?

A conveyor section that delivers objects to another conveyor

The initials HSD refer to what?

High Speed Diverter

A vertical sorter is what?

A device that sorts objects to conveyors that are stacked vertically

What does a bearing cap do on a conveyor roller?

Covers the exposed end of the shaft and the bearing

Name three common types of belt lacing.

Vulcanizing, alligator, clipper

A conveyor’s speed is determined by what?

The gear box or VFD drive setting