FCU 500, FCU 505 · Edition 02.17
47
Valve proving system
tL = P59
tM = P56
+
–
tL = P59
tM = P56
pZ >
3pu
4
+
–
V2 OK
pZ >
pu
4
V1
OK
V1
V2
OK
V1
V1
V1
OK
V2
V2
V2
V1
V2
pZ >
3pu
4
+
–
pZ >
pu
4
+
–
tL = P59
tM = P56
V1
V1
tL = P59
tM = P56
V2
V2
pZ >
pu
4
+
–
V
p1
V1
V2
p
u
p
z
p
d
PZ
PZ
3p
u
/4
p
u
/4
Program
A
Program
B
START
Program A (reduced testing time)
Valve V1 opens for the opening time t
L
set in param-
eter 59. V1 closes again. During the measurement
time t
M
, the tightness control checks the pressure p
Z
between the valves.
If pressure p
Z
< 3p
u
/4, valve V2 is leaking.
If pressure p
Z
> 3p
u
/4, valve V2 is tight. Valve V2 is
opened for the set opening time t
L
. V2 closes again.
During the measurement time t
M
, the tightness control
checks the pressure p
Z
between the valves.
If pressure p
Z
< p
u
/4, valve V1 is tight.
If pressure p
Z
> p
u
/4, valve V1 is leaking.
Program B (reduced testing time)
Valve V2 opens for the opening time t
L
set in param-
eter 59. V2 closes again. During the measurement
time t
M
, the tightness control checks the pressure p
Z
between the valves.
If pressure p
Z
> p
u
/4, valve V1 is leaking.
If pressure p
Z
< p
u
/4, valve V1 is tight. Valve V1 is
opened for the set opening time t
L
. V1 closes again.
During the measurement time t
M
, the tightness control
checks the pressure p
Z
between the valves.
If pressure p
Z
< 3p
u
/4, valve V2 is leaking.
If pressure p
Z
> 3p
u
/4, valve V2 is tight.