GE GL317D Instruction Manual page 130

Technical data
SF gas
6
Example
SF gas filling
6
02- 2017
Installation
Calculation of the SF
for using the pressure gauge (tool)
The table below gives the SF
Absolute pressure at 20C(68F)
Filling absolute pressure for the insula-
p
re
tion
i.e. effective pressure
at 20C(68F) and 101.3 kPa
Filling rated effective pressure
p
re
for the insulation
Alarm effective pressure for the
p
ae
insulation
Minimal effective pressure for
p
me
the insulation
SF gas density
6
p
re
p
ae
p
me
Minimum admissible temperature
up to
Determination of the circuit- breaker's filling pressure with SF
Parameters
p
re
SF gas rated filling effective
6
pressure for the insulation
Ambient temperature
Local atmospheric pressure
The table below gives the calculation steps of the pure SF
Step Action
1 In the chart (page 4) "Values of the
SF gas effective pressures in
6
accordance with the temperature",
read the p value on the
re
tC = 5 row.
2 Calculate the difference of the
atmospheric pressure :
0,1013 - 0,0932
3 Calculate the rated effective pres-
sure p :
re
0,510 + 0,0081
4 Filling is carried out to the calcu-
lated pressure, plus 0,01 MPa,
that is to say :
0,5181 + 0,01
GE Information
gas filling pressure
6
gas characteristics :
6
+ 0,01
- 0
0.45 MPa (p
+ 0,02
- 0
+ 0,02
- 0
Pure SF
0.65 MPa
(94.27 p.s.i.)
0.55 MPa
(79.77 p.s.i.)
+0.03 MPa)
me
(65.27 p.s.i.)
0.42 MPa
(60.92 p.s.i.)
3
42,38 kg/m
3
35,38 kg/m
3
33,31 kg/m
- 35C
gas.
6
Values
0,55 MPa
(79.77 psi)
5C
93,2 kPa
filling pressure :
6
Result
0,51 MPa
0,0081 MPa
0,5181 MPa
gas filling pressure
6
0,5281 MPa
L31- 921EN/03
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