Index

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A

B

C

D

E

F

G

H

I

J

K

L

M

N

O

P

Q

R

S

T

U

V

W

X

Z

U UHV system classification, xxv-vi uncompensated transmission lines, 889-90 ungrounded systems, 762-65, 830-31 unfavourable operating conditions, 319-24, 327-31, see also hazardous locations units, 370 universal motors, 31-32 unrestricted ground fault protection, 788-89