7 SG9H 70 en
9
3.5
Piping
Table 3 provides the recommended tube sizes in accord-
ance with actuator sizes. Tube sizes are the minimum values
allowed.
Connect the air supply to S.
Connect C1 and C2 to the actuator, see Fig. 5. C1 must be
plugged if single-acting actuator.
Liquid sealants, such as Loctite 577 are recommended for
the pipe threads.
The air supply must be clean, dry and oil-free instrument air,
see Section 1.4.
CAUTION:
Do not exceed the permitted supply pressure of the
SwitchGuard!
CAUTION:
It is important to note, that SwitchGuard mounted on
a spring actuator MUST be connected only as single-
acting. See Fig. 5.
NOTE:
An excess of sealant may result in faulty operation of the
controller.
Sealing tape is not recommended.
Ensure that the air piping is clean.
Table 2
Spring rates
Actuator type
Spring rate (bar/psi)
B1JK
3 / 43
B1J
4.2 / 61
B1JV
5.5 / 80
QPX_A
1.4 / 20
QPX_B
2.8 / 41
QPX_C
4.1 / 60
QPX_D
5.5 / 80
Adjust regulator pressure to a level that is max 1 bar (14.5 psi)
+ spring rate.
CAUTION:
Always adjust the maximum valve speed parameter
according to Table 3. Erroneous value may cause insta-
bility.
CAUTION:
Extra pneumatics instrumentation (i.e. QEV, VB, etc.) is
not allowed with SwitchGuard when opening and clos-
ing stroke profiles are used, i.e. when stroking times
are set other than 0 s.
CAUTION:
The stroking times mentioned in Table 4 are trendset-
ting. They are measured with 5 bar supply air pressure,
but may vary significantly due to different factors
such as, but not limited to, pressure difference of the
valve, the stiction of the actuator, supply air pressure,
the capacity of the supply air system and the dimen-
sions of the supply air pipeline.
NOTE:
When opening/closing times are defined in the Table 3,
the specified spool valve size can be used with that actua-
tor size. If there is '-' sign in the table or if smaller actuators
than shown in the table are used, please contact Metso.
CAUTION:
The air supply system must be of sufficient size and
capacity to ensure that at maximum flow during valve
movement the pressure at the SwitchGuard must not
fall below 3 bar. Also note that if the air supply system
allows the pressure at the SwitchGuard to fall below
the actuator minimum supply pressure during valve
movement the stroke speed will be affected.
