a hand rope was used to ______,______ and ______of the elevator motor before magnetic switches/relays became available?
stop, start and reverse
... [Show More] direction
after magnetic switches became available, ______ ______ were installed in the elevator car to operate the elevator.
push buttons
the biggest problem with ac controls is ______ accuracy
floor
the sytsems used to drive motors, generators, brakes and transformers are called
power controls
new control systems called _____ are being installed on old AC elevators to improve ride and floor accuracy
vvvf (varriable voltage variable frequency)
____________ __________varied armature resistance in early DC elevators
rheostatic control
early hydraulic elevators used to ______ ______ ______ and level back down
overshoot the floor
taller buildings were made possible by removing the limitations of the _________ ________ with the introduction of the _________ ______
winding drum, traction sheave
which wiring diagram would be more useful in troubleshooting? field wiring diagram or schematic diagram
schematic wiring diagram
on straight line diagrams, fuses , relays , and contacts are all represented by _____
symbols
what does VOM stand for?
volt, ohm , milliampere
T or F? digital meters can measure voltage with a dead battery?
false
clipping one meter lead to a _______ ______ is a safety precaution when working on live equipment
reference point
when switvhing the range selector you should always disconnect the ____ ____
meter leads
before using your meter on the ohm scale you should always check the controller for____
voltage
T or F? dropping a metere will probably not harm it?
false
T or F? never touch voltage with the meter set to read ohms?
true
T or F? never put the meter probes on a voltage with the meter set to read current
true
T or F? careless meter switching can harm solid state equipment
true
when testing low voltages on solid state boards ____ should be insulated
adjacent pins
the selector switch of an analog meter would be set to rx1to read ____
resistance
before testing resistance with any VOM the leads should be ____ ____to zero the meter
touched together
digital meters will automatically indicate if the resistance is in ____ ____ or ____
ohms, kilohms, megaohms
T or F? once the analog meter has been zeroed you dont need to do it again when you change ranges
false
the most important tool an elevator mechanic has is ____ ____
common sense
when a problem is interemittent it will be beneficial to ____ ____ of building personnel or passengers
ask questions
when testing circuits a _____ should be used
meter
you should have an exact count of all ____ carried in your tool box
jumpers
all circuits must be treated as live circuits untl they are proven ____
dead
T or F? when working on a single car in a multi car system, pulling the mainline switch kills all cross connections on that car
false [Show Less]