Siemens LMV50 Series Manual page 62

Recommendation
Β
Determination of valve
proving
leakage rate
Legend
Examples
62/327
Building Technologies
Perform gas valve proving during shutdown.
Caution!
The evacuation and filling times as well as the test times at atmospheric
pressure or mains pressure must be set by the OEM, for each individual plant
and in accordance with the requirements of EN 1643.
In particular, it must be ensured that the 2 test times are set correctly. It must also be
checked whether – on the specific application – it is permitted to introduce into the
combustion chamber the gas required for testing.
The test times are safety-related.
After a reset, or in the event gas valve proving has been aborted or prevented, the
burner control effects gas valve proving during the next startup sequence (only if gas
valve proving is activated).
Example of aborted gas valve proving:
When the safety loop or the start prevention input for gas (containing pressure switch-
min) opens during the time gas valve proving is performed.
The input for the valve proving function can also be used for the CPI (valve closure
contact).
Note!
If gas valve proving is parameterized to take place with startup and shutdown, the gas
valves must perform additional switching cycles. This means that wear and tear of the
gas valves will increase.
Parameter ValveProvingType (No VP / VP startup / VP shutdown / VP
stup/shd)
Config_PS-VP/CPI (PS-VP / CPI Gas / CPI Gas+Oil / CPI Oil)
VP_EvacTme
VP_TmeAtmPress
VP_FillTme
VP_Tme_GasPress
(P G - P w )

Q Leakage =
Q Leakage in l/h
P G in mbar
P W in mbar
P atm in mbar
V in l
t Test in s
Refer to chapter Commissioning instructions for LMV5 / gas valve proving / valve
proving.
Basic Documentation LMV5...
4 Burner control
V 3600
• •
P atm t Test
•
Leakage rate in liters per hour
Overpressure in the piping section between the valves to be tested, at the
beginning of the test phase
Overpressure adjusted on the pressure switch (normally set to 50%
of the gas inlet pressure)
Absolute air pressure (1,013 mbar normal pressure)
Volume in the piping section between the valves to be tested, including the
volume in the valves themselves, plus any pilot section (Gp1)
Test time
CC1P7550en
22.05.2018