問題一覧
1
to vector a 3 phase system it is important to establish a of the phases?
fixed reference
2
the strength of a electro magnetic field in a transformer is dependent on the ease on which the core is magnetized, amount of current flowing and the ?
number of turns in the winding
3
if there is a slash on the transformer name plate
operate at 2 voltages
4
the transformer ratio is 10:1 the secondary voltage is 120 volts
1200
5
when paralleling 2 transformers the two ______ must be writhing 5 %
impedance
6
medium and large sized transformers use___type of wire
square and rectangle
7
illustrations using vectors can show, phase sequence and?
phase angle
8
clip on ammeter should be taken during
at the peak
9
the H2 on a single bushing can is usually?
connected inside the can
10
isolation link of a current limiting fuse in a underground transformer
between the replaceable fuse and the primary coil
11
a transformer changes the voltage and current from one level because of
number of turns in each coil
12
a test equipment used to test insulation breakdown
megometer
13
why we use electrical measuring instruments
greater measuring capability
14
in a csp the secondary breaker will not
energize the primary side of can
15
if you hold a csp handle on C the secondary breaker will on permanent fault
reopen
16
the voltage level that can flash over the outside of equipment
basic impulse
17
a typical transformer consist of
core and coil assembly
18
when working a csp it’s important to do what to the can before work
denergize both primary and secondary
19
a transformer that is energized but under no load can draw as much as?
5%
20
the electrical worker who is familiar with vector____ can plot any 3 phase system within 30
wheel
21
if the transformer is equipped with tap changers it must never be
operated while energized
22
if two transformers in Parallel and one blows the other transformer will
back feed the blown transformer
23
when performing a polarity test on a subtractive transformer the volt meter will read ____ than the source voltage
less
24
transformer with missing or damaged name plate should be polarity tested and marked where?
on the can
25
a voltage indicator may not direct voltage on a wire that is?
shielded