GE SF6 User Manual

Installation
Calculation of th e SF
6
gas f illing pressure
for using the p ressure gauge (tool)
GE Information08- 2016 L31- 922EN/04
2/4
Techn ical data
SF
6
gas
The table below gives the SF
6
gas characteristics :
Absolute pressure at 20C(68F)
p
re
Filling absolute pressure for the insula-
tion
0.75 MPa
(108.79 p.s.i.)
i.e. effective pressure
at 20C(68F) and 101.3 kPa
p
re
Filling rated effective pressure
for the insulation
+0,01
-0
0.65 MPa
(94.27 p.s.i.)
p
ae
Alarm effective pressure for the
insulation
+0,02
-0
0.54 MPa (p
me
+0.03 MPa)
(78.32 p.s.i.)
p
me
Minimal effective pressure for
the insulation
+0,02
-0
0.51 MPa
(73.97 p.s.i.)
SF6 gas density
p
re
49.59 kg/m
3
p
ae
41.66 kg/m
3
p
me
39.55 kg/m
3
Minimum admissible temperature
up to
-30C
Example
Determination of the circuit- breaker’ s filling pressure with SF
6 gas.
Parameters
Values
p
re
SF
6
gas rated filling effective
pressure for the insulation
0,65 MPa
(94.27 psi)
Ambient temperature 5C
Local atmospheric pressure 93,2 kPa
SF
6
gas filling
The table below gives the calculation steps of the pure SF
6
filling pressure :
Step
Action Result
1 In the chart (page 4) “Values of the
SF
6
gas effective pressures in
accordance with the temperature”,
read the p
re
valueonthe
tC=5row.
0,603 MPa
2 Calculate the difference of the
atmospheric pressure :
0,1013 - 0,0932
0,0081 MPa
3 Calculate the rated effective pres-
sure p
re
:
0,603 + 0,0081
0,6111 MPa
4 Filling is carried out to the calcu-
lated pressure, plus 0,01 MPa,
that is to say :
0,6111 + 0,01
Pure SF
6
gas filling pressure
0,621 1 MPa

GE SF6 Specifications

General

Brand	GE
Model	SF6
Category	Circuit breakers
Language	English