Exam (elaborations)
LINEMAN APPRENTICE TRANSFORMER THEORY QUESTIONS AND ANSWERS
- Course
- Institution
LINEMAN APPRENTICE TRANSFORMER THEORY QUESTIONS AND ANSWERS...
[Show more]
Content preview
LINEMAN APPRENTICE TRANSFORMER THEORYQUESTIONS AND ANSWERS
Why is a Closed Wye - Closed Delta primary neutral floated? - ANSWER To
prevent the backfeed of full primary voltage if a line cutout is blown.
Why would a 4th cutout be installed on the primary neutral of a closed Wye -
closed Delta Bank? - ANSWER To prevent Ferroresonance while switching.
What KVA capacity is the bank rated for on an open transformer bank? -
ANSWER 86.6% of nameplate ratings.
Describe the term "Backfeed" - ANSWER To feed the primary coil through
the secondary coil.
What should be done before climbing above a transformer? - ANSWER Check
the tank ground is intact, deenergize the high side and remove secondary leads.
What determines voltage drop amount when a transformer is at full load? -
ANSWER Impedance
Explain polarity of a transformer. - ANSWER Relative direction of current flow
primary to secondary.
When paralleling or banking transformers, the impedance must be within
_____% of each other? - ANSWER 10%
, What would you have in KVA capacity if you took an open delta bank and
closed it? - ANSWER 57.7% of the original 3 transformers. OR 86.6 of the
remaining 2.
How much capacity would you pick up by operating a closed delta bank vs. an
open delta bank? - ANSWER (57.7 to 100%) = 42.3%
What do you have to do to the neutral connection for a closed wye -closed wye
transformer bank? - ANSWER Tie the primary neutral.
What is the purpose of the case ground on a transformer? - ANSWER To keep
the transformer case from becoming energized and on a single bushing
transformer the case ground is the H2 connection.
Name the types of transformer banks you can make with two or three
transformers. - ANSWER Wye-Wye, Wye-Delta, Delta-Delta, Delta-Wye,
Open Wye-Delta, Open Delta-Delta
What does CSP mean? - ANSWER Completely self protected
On a CSP transformer, what coil is the circuit breaker on? - ANSWER
Secondary
Taps are for two purposes, name them. - ANSWER Control voltage to the
customer and correct low primary voltage *raise the tap to lower the secondary
voltage*
T or F, Two cutouts and arrestors are needed on a wye connected transformer. -
ANSWER FALSE
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 luzlinkuz. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for $11.49. You're not tied to anything after your purchase.
Can Stuvia be trusted?
4.6 stars on Google & Trustpilot (+1000 reviews)
79223 documents were sold in the last 30 days
Founded in 2010, the go-to place to buy study notes for 14 years now