Samson foundation 3787, Mounting And Operating Instructions, Page: 14 / 96

2.2 Attachment acc. to IEC 60534-6
The positioner is attached according to
NAMUR as shown in Fig. 4 using an adapt-
er housing. The valve travel is transmitted
via the lever (18) and the shaft (25) to the
bracket (28) in the adapter housing and
then to the coupling pin (27) located on the
lever of the positioner.
To attach the positioner, you will require the
mounting parts listed in Table 4. Which
lever should be used depends on the rated
valve travel.
The positioner must be attached to the
adapter housing with the
arrow
on the
black case cover pointing away from the
diaphragm actuator towards the valve.
Exception: Control valves in which the plug
closes the seat area when the actuator stem
retracts. In this case, the arrow must point
towards the diaphragm actuator.
If the adapter housing cannot be mounted
between the actuator and valve (e.g. be-
cause the actuator is from another manufac-
turer), the
arrow on the case cover must
point towards the valve!
Note!
For faster control valves with a transit time
less than 0.6 seconds, replace the filter in
the signal pressure output (output 38) with a
screw-in throttle (see Accessories table).
2.2.1 Mounting sequence
Refer to Tables 4 and 5 on page 16 for re-
quired mounting parts.
Note!
Prior to mounting the parts, apply signal
pressure to the actuator so that the valve is
set to 50 % of its travel. This is the only way
to make sure that the lever (18) and bracket
(28) are exactly aligned.
Control valve with cast yoke
1. Use countersunk screws to fix the plate
(20) to the coupling which connects the
plug stem and actuator stem. With actu-
ators 2100 and 2800 cm
2 , use addi-
tional mounting bracket (32).
2. Remove rubber plug from the adapter
housing and fasten the housing to the
NAMUR rib with hexagon head screw.
Control valve with rod-type yoke
1. Screw plate (20) to the follower clamp
of the plug stem.
2. Screw the studs (29) into the adapter
housing.
3. Place the housing with the plate (30) on
either the right or left side of the valve
stem and fasten tight using the nuts
(31). On doing so, make sure the hous-
ing is aligned at a height which will
still allow the lever (18) to be attached
horizontally.
4. Screw the pin (19) into the center row
of holes in the plate (20) and lock into
place so that it is located approximately
above the correct lever marking (1 to 2)
14
EB 8383-1 EN
Attachment to the control valve