Siemens SIPROCESS GA700 Compact Operating Instructions

Calculation of leakage rate
A gas path is considered su󹪟ciently tight for normal heated modules when the leakage rate QL
from a gas line (containment system = CS) is less than 10
-3
hPa l / s.
• Calculation of the leakage rate QL: QL = V Δp / t
The max. permissible leakage rate Q
L
always refers to the max. pressure occurring in the CS.
The leakage test is performed with air or N
2
. In metal piped analyzer modules, H
2
can also be
introduced during operation, which has half the viscosity of N
2
. Therefore, a max. permissible
leakage rate of Q
L
= 5∙10
-4
hPa l / s is applied to metal piped analyzer modules.
• Determination of the test conditions
Monitoring of the max. permissible leakage loss is carried out according to the pressure drop
method. Here, the absolute pressure p of the gas (air or N
2
) enclosed in the CS with volume V
is observed, which - if leakage is present - drops by Δp within a speci󹪝ed time interval t. The
amount of duck drop is a measure of the tightness of the CS.
Considering the leakage losses to be determined at the respective device type, a max.
permissible pressure drop Δp
max
results.
It is calculated as follows:  Δp
max
= t Q
L
/ V
• Other
If the test volume V
new
deviates from the V assumed in the calculation of the test values, the
test value Δp
max
must be multiplied by a correction factor k, which is calculated as follows:
k = V / V
new
Device variant Test pressure p / hPa
rel.
Gas path volume V
0
/
ml
Max. permissible leak‐
age rate QL/(hPa ∙ l / s)
Max. perm. pressure
drop Δp
max
/ hPa
Normal heated mod‐
ule, MG path piped,
VG path tubed
100 8 10
-3
37
Normal heated mod‐
ule, MG path tubed,
VG path tubed
100 10 10
-3
30
Normal heated mod‐
ule, MG path tubed,
VG path tubed, with‐
out / with VG pressure
switch
500 7 / 8 10
-3
42 / 37
Normal heated mod‐
ule, MG path piped,
VG path tubed, with‐
out / with VG pressure
switch
2000 6 / 7 5 ∙10
-4
25 / 21
High-temperature
module, MG path pi‐
ped, RG path piped,
without / with RG
pressure switch
2000 6,5 / 7,5 5 ∙
ּ
10
-4
23 / 20
Field module, with‐
out / with RG pressure
switch
2000 15 10
-4
2
Commissioning
5.4Checking gas paths for leaks
SIPROCESS GA700 rack and wall mounted devices
Compact Operating Instructions, 06/2023, A5E35134047-AB 75

Siemens SIPROCESS GA700 Specifications

General

Brand	Siemens
Model	SIPROCESS GA700
Category	Measuring Instruments
Language	English