Table 2. - Manufacturer's P. F. (power factor) limits for bushings
Manufacturer
Bushing type
or class
Initial P.F.
for new
bushings, at
Dangerous P. F.
value at
20
E
C (%)
General electric
A
6.0
8.0
B
10.0
12.0
F
1.5
2.0
L
3.0
4.0
LC
2.5
3.5
OF
2.6
6.0
S
3.5
6.0
U
1.0
1.5
Lapp bushings
POC
0.5
PRC
0.7-1.2
Ohio Brass manufactured prior
to 1926 and after 1938
to 1926 and after 1938
ODOF
G
L
1-10
Initial P.F. = 22
Ohio Brass manufactured 1926
to 1938, inclusive
to 1938, inclusive
ODOF
G
L
2-4
Initail P.F. = 16
Ohio Brass
Class GK type C
04.-0.6
Class LK type A
0.6-0.7
Pennsylvania Transformer
P
PA
PB
PB
0.5
1.0
Westinghouse
D
6.0
O
1.4
OCB & Inst. Trans. 69-kV
and
Below
3.5
OCB & Inst. Trans. 92-kV
to
138-kV
2.8
Power & Dist. Trans. OCB
&
161-kV to 288-kV.
2.0
(FIST 3-2 11/91)
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