Honeywell Krom Schroder BCU 580 Technical Information page 32

Valve proving system
+
Program A
V1
t L = P59
V1
V1
t M = P56
–
p u
p Z >
2
+
V2
V2
OK
V2
t L = P59
V2
t M = P56
+
p u
p Z >
2
–
V1 OK V1
BCU 580 · Edition 11.15l
START
–
p u
p Z >
2
Program B
t L = P59
V2
PZ
p /2
u
p
z
t M = P56
+
p Z >
V1
t L = P59
t M = P56
–
p Z >
V2
Program B
Valve V2 opens for the set opening time t
again. During the measurement time t
control checks the pressure p
If pressure p
If pressure p
V2
opened for the set opening time t
During the measurement time t
checks the pressure p
V2
If pressure p
If pressure p
The tightness test can only be performed if pressure p
p u
downstream of V2 is around atmospheric pressure and
2
–
the volume downstream of V2 is at least 5 × higher than
V1 OK the volume between the valves.
V1
V1
p u
2
+
V2 OK
between the valves.
Z
> p /2, valve V1 is leaking.
Z u
< p /2, valve V1 is tight. Valve V1 is
Z u
. V1 closes again.
L
, the tightness control
M
between the valves.
Z
< p /2, valve V2 is leaking.
Z u
> p /2, valve V2 is tight.
Z u
. V2 closes
L
, the tightness
M
d
32