Mechanics Exam Questions & Answers |
100% Correct Answers | Verified | Latest
2024 Version
** An MOV burns out, you replace it but cannot read voltage or resistance. What should you do? -
Replace it with a larger one (630)
* On a Ward-Leonard circuit, the brake is set but the motor is trying t...
Mechanics Exam Questions & Answers |
100% Correct Answers | Verified | Latest
2024 Version
** An MOV burns out, you replace it but cannot read voltage or resistance. What should you do? -
✔✔Replace it with a larger one (630)
* On a Ward-Leonard circuit, the brake is set but the motor is trying to slip through the brake. What
circuit is the issue? - ✔✔Suicide circuit (425)
** A Hydro runs up with no load but does not run up with a full load. What is the issue? - ✔✔The relief
valve is set too low (805)
** Runby for a 1:1 car hits the CWT buffer 4" below the top landing. The CWT runby should be set at 18".
How much should the ropes be shortened? - ✔✔22" for 1:1.
For a 2:1 with the same issue is 44".
** You need to work on a freight door retiring cam. You LOTO the mainline disconnect but there is still
power to the cam. What circuit is still hot? - ✔✔Mainline disconnect (535)
** The contractor requests that the vertical center of the Rack and Pinion hoist be moved. How is this
accomplished? - ✔✔Adjust Tie downs/Wall ties (805)
** Working pressure on a Hydro is 400 PSI. What is the correct Relief Valve Setting? - ✔✔600 PSI Max.
(805)
400 psi x 150% = 600 psi
** A contractor wants to raise the car speed from 100 FPM to 125 FPM. It currently has a 12" sheave.
What size sheave is required? - ✔✔15"
(125 /100 = 1.25 1.25 x 12 = 15)
, ** There is slight arcing at the Brushes and Commutator. What actions must be taken? - ✔✔None. (430)
"Heavy arcing is due to light brush pressure. Mechanical wear indicates heavy brush pressure.
** How much resistance is normally measured across a normally closed switch ? - ✔✔1.2 ohms or 1 to 2
ohms
** A car traveling in the hoistway always stops at the same point and blows a fuse. What is the problem?
- ✔✔Traveling cable has a cut or short
** How is a Class 1 (yearly) buffer test performed? - ✔✔At slow speed and the buffer must return in 90
seconds. (555) *(60 seconds is acceptable) (90 seconds is code)
5 year test (Class 5) is car at rated load and speed. Buffer must return in 90 seconds. CWT at rated speed
and buffer must return in 90 seconds.
** How many Strain Supports are required on a 350' raceway? - ✔✔4
One for every 100'
** How is Stainless steel drilled out? - ✔✔Slow speed and constant pressure (205)
** What are the required amount of clips for Wedge Shackles and what is their spacing? - ✔✔At least 2,
with the first being 4 times the diameter of the rope from the top of shackle.
Second is 8 times the diameter of the rope from the first.
** Car is loaded with 125% and sinks. Why? - ✔✔Slipped through the brake.
** A 300 Ohm resistor burns out. You don't have a 300 Ohm resistor to replace it. What can you use to
make up the resistor? - ✔✔2 600 Ohms resistors in Parallel. "The resistance is half of the highest rating in
a parallel circuit.
3, 225 Ohm resistors in parallel equal 75 Ohms.
The benefits of buying summaries with Stuvia:
Guaranteed quality through customer reviews
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through credit card or Stuvia-credit for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying these notes from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller hov. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for $7.99. You're not tied to anything after your purchase.
