550 Machine room maintenance

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The setting of a car governor electrical contact on cars 500 foot a minute or less must be below what percentage less then the car governor tripping speed

10%

The mechanical tripping speed of the governor cannot be lower than what percentage of the car speed

115%

What is the maximum soldering iron wattage for use on printed circuit boards

40w

What circuit operates after the break fully energizes to reduce break coil current

Brake cooling

What could be the cause of an intermittent loop overload trip

Brake not lifting, properly the car is overloaded,excessive motor bearing friction

What really uses oil or silicon fluid To control the time in which the core and piston rise

Dashpot overload

What should be observed before performing maintenance on a really logic controller

Have replacement parts available, protect the area below your work area, lock and tag out the mainline

What must be done before disassembling a machine brake

Land the counterweight

What area of operation is most affected if all brushes in a machine or changed at one time

Leveling

Sealed bearings should be lubricated at what frequency

Never

What is the result of too large of a relay Armature airgap

Positive pick up may be lost

What is the purpose of a relay Armature residual guard

Prevents relay from failing to drop due to residual magnetism

Which of the following is the most important part of any job in an elevator industry

Safety procedures

How is a magnetic blowout coil wired in relation to the circuit it's contact controls

Series

What function does a starter panel perform

Starting the MG set

What type of fuse is used in a circuit where short duration, high currents occur in normal operation

Time-delay

What is the process called that is applying a small amount of solder on the soldering tip to allow maximum heat transfer

Tinning

Why is it necessary to isolate a component before taking an ohmmeter measurement

To eliminate parallel resistance

What is the purpose of options-isolators On solid state controllers

To interface high and low voltage

What type of rectifiers lose ability to deliver rated Current as they age

selenium


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